Standard Review Plan for Review of License Renewal Applications for Nuclear Power Plants (NUREG-1800, Initial Report)
On this page:Publication Information
Date Published: July 2001
U.S. Nuclear Regulatory Commission
Office Nuclear Reactor Regulation
Washington, DC 20555-0001
Table of Contents
- Publication Information
- Abstract
- Abbreviations
- Introduction
- Chapter 1: Administrative Information
- Chapter 2: Scoping and Screening Methodology for Identifying Structures and Components Subject to Aging Management Review and Implementation Results
- 2.1 Scoping and Screening Methodology
- 2.1.1 Areas of Review
- 2.1.2 Acceptance Criteria
- 2.1.3 Review Procedures
- 2.1.4 Evaluation Findings
- 2.1.5 Implementation
- 2.1.6 References
- 2.2 Plant-Level Scoping Results
- 2.2.1 Areas of Review
- 2.2.2 Acceptance Criteria
- 2.2.3 Review Procedures
- 2.2.4 Evaluation Findings
- 2.2.5 Implementation
- 2.2.6 References
- 2.3 Scoping and Screening Results: Mechanical Systems
- 2.3.1 Areas of Review
- 2.3.2 Acceptance Criteria
- 2.3.3 Review Procedures
- 2.3.4 Evaluation Findings
- 2.3.5 Implementation
- 2.3.6 References
- 2.4 Scoping and Screening Results: Structures
- 2.4.1 Areas of Review
- 2.4.2 Acceptance Criteria
- 2.4.3 Review Procedures
- 2.4.4 Evaluation Findings
- 2.4.5 Implementation
- 2.4.6 References
- 2.5 Scoping and Screening Results: Electrical and Instrumentation and Controls Systems
- Chapter 3: Aging Management Review Results
- 3.1 Aging Management of Reactor Vessel, Internals, and Reactor Coolant System
- 3.1.1 Areas of Review
- 3.1.2 Acceptance Criteria
- 3.1.3 Review Procedures
- 3.1.4 Evaluation Findings
- 3.1.5 Implementation
- 3.1.6 References
- 3.2 Aging Management of Engineered Safety Features
- 3.2.1 Areas of Review
- 3.2.2 Acceptance Criteria
- 3.2.3 Review Procedures
- 3.2.4 Evaluation Findings
- 3.2.5 Implementation
- 3.2.6 References
- 3.3 Aging Management of Auxiliary Systems
- 3.3.1 Areas of Review
- 3.3.2 Acceptance Criteria
- 3.3.3 Review Procedures
- 3.3.4 Evaluation Findings
- 3.3.5 Implementation
- 3.3.6 References
- 3.4 Aging Management of Steam and Power Conversion System
- 3.4.1 Areas of Review
- 3.4.2 Acceptance Criteria
- 3.4.3 Review Procedures
- 3.4.4 Evaluation Findings
- 3.4.5 Implementation
- 3.4.6 References
- 3.5 Aging Management of Containments, Structures, and Component Supports
- 3.5.1 Areas of Review
- 3.5.2 Acceptance Criteria
- 3.5.3 Review Procedures
- 3.5.4 Evaluation Findings
- 3.5.5 Implementation
- 3.5.6 References
- 3.6 Aging Management of Electrical and Instrumentation and Controls
- Chapter 4: Time-limited Aging Analyses
- 4.1 Identification of Time-limited Aging Analyses
- 4.1.1 Areas of Review
- 4.1.2 Acceptance Criteria
- 4.1.3 Review Procedures
- 4.1.4 Evaluation Findings
- 4.1.5 Implementation
- 4.1.6 References
- 4.2 Reactor Vessel Neutron Embrittlement Analysis
- 4.2.1 Areas of Review
- 4.2.2 Acceptance Criteria
- 4.2.3 Review Procedures
- 4.2.4 Evaluation Findings
- 4.2.5 Implementation
- 4.2.6 References
- 4.3 Metal Fatigue Analysis
- 4.3.1 Areas of Review
- 4.3.3 Review Procedures
- 4.3.4 Evaluation Findings
- 4.3.5 Implementation
- 4.3.6 References
- 4.4 Environmental Qualification (EQ) of Electric Equipment
- 4.4.1 Areas of Review
- 4.4.2 Acceptance Criteria
- 4.4.3 Review Procedures
- 4.4.4 Evaluation of Findings
- 4.4.5 Implementation
- 4.4.6 References
- 4.5 Concrete Containment Tendon Prestress Analysis
- 4.5.1 Areas of Review
- 4.5.2 Acceptance Criteria
- 4.5.3 Review Procedures
- 4.5.4 Evaluation Findings
- 4.5.5 Implementation
- 4.5.6 References
- 4.6 Containment Liner Plate, Metal Containments, and Penetrations Fatigue Analysis
- 4.6.1 Areas of Review
- 4.6.2 Acceptance Criteria
- 4.6.3 Review Procedures
- 4.6.4 Evaluation Findings
- 4.6.5 Implementation
- 4.6.6 References
- 4.7 Other Plant-specific Time-limited Aging Analyses
- Appendix A: Branch Technical Positions
Abstract
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The Standard Review Plan for Review of License Renewal Applications for Nuclear Power Plants (SRP-LR) provides guidance to Nuclear Regulatory Commission staff reviewers in the Office of Nuclear Reactor Regulation. These reviewers perform safety reviews of applications to renew nuclear power plant licenses in accordance with Title 10 of the Code of Federal Regulations Part 54. The principal purposes of the SRP-LR are to ensure the quality and uniformity of staff reviewers and to present a well-defined base from which to evaluate applicant programs and activities for the period of extended operation. The SRP-LR is also intended to make information about regulatory matters widely available, to enhance communication with interested members of the public and the nuclear power industry, and to improve their understanding of the staff review process. The safety review is based primarily on the information provided by the applicant in a license renewal application. Each of the individual SRP-LR sections addresses (1) who performs the review, (2) the matters that are reviewed, (3) the basis for review, (4) the way the review is accomplished, and (5) the conclusions that are sought.
Paperwork Reduction Act Statement
The information collections contained in this NUREG are covered by the requirements of 10 CFR Parts 50 and 54, which were approved by the Office of Management and Budget, approval numbers 3150-0011 and 3150-0155.
Public Protection Notification
If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
Abbreviations
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| AFW | auxiliary feedwater |
| AMP | aging management program |
| AMR | aging management review |
| ANL | Argonne National Laboratory |
| ANSI | American National Standards Institute |
| ASME | American Society of Mechanical Engineers |
| ASTM | American Society for Testing and Materials |
| ATWS | anticipated transients without scram |
| B&W | Babcock & Wilcox |
| BWR | boiling water reactor |
| BWRVIP | Boiling Water Reactor Vessel and Internals Project |
| CASS | cast austenitic stainless steel |
| CDF | core damage frequency |
| CE | Combustion Engineering |
| CFR | Code of Federal Regulations |
| CLB | current licensing basis |
| CRD | control rod drive |
| CUF | cumulative usage factor |
| DBA | design basis accident |
| DBE | design basis event |
| DG | Draft Regulatory Guide |
| DOR | Division of Operating Reactors |
| ECCS | emergency core cooling system |
| EDG | emergency diesel generator |
| EFPY | effective full power year |
| EPRI | Electric Power Research Institute |
| FAC | flow-accelerated corrosion |
| FR | Federal Register |
| FSAR | Final Safety Analysis Report |
| GALL | Generic Aging Lessons Learned |
| GE | General Electric |
| GL | generic letter |
| GSI | generic safety issue |
| HAZ | heat-affected zone |
| HELB | high-energy line break |
| HPCI | high-pressure coolant injection |
| HVAC | heating, ventilation, and air conditioning |
| I&C | instrumentation and control |
| IASCC | irradiation assisted stress corrosion cracking |
| IEEE | Institute of Electrical and Electronics Engineers |
| IGA | intergranular attack |
| IGSCC | intergranular stress corrosion cracking |
| IN | information notice |
| INPO | Institute of Nuclear Power Operations |
| IPA | integrated plant assessment |
| IPE | individual plant examination |
| IPEEE | individual plant examination of external events |
| IR | insulation resistance |
| ISI | inservice inspection |
| ITG | Issues Task Group |
| LCD | liquid crystal display |
| LED | light-emitting diode |
| LER | licensee event report |
| LOCA | loss-of-coolant accident |
| Ltop | low-temperature overpressure protection |
| MIC | microbiologically influenced corrosion |
| MRV | minimum required value |
| NDE | nondestructive examination |
| NDT | nil-ductility temperature |
| NEI | Nuclear Energy Institute |
| NFPA | National Fire Protection Association |
| NPS | nominal pipe size |
| NRC | Nuclear Regulatory Commission |
| NRR | NRC Office of Nuclear Reactor Regulation |
| NSAC | Nuclear Safety Analysis Center |
| NSSS | nuclear steam supply system |
| ODSCC | outside diameter stress corrosion cracking |
| OM | operation and maintenance |
| P&ID | piping and instrument diagrams |
| PLL | predicted lower limit |
| PRA | probabilistic risk analysis |
| PT | penetrant testing |
| P-T | pressure-temperature |
| PTS | pressurized thermal shock |
| PWR | pressurized water reactor |
| PWSCC | primary water stress corrosion cracking |
| QA | quality assurance |
| RCIC | reactor core isolation cooling |
| RCPB | reactor coolant pressure boundary |
| RCS | reactor coolant system |
| RG | Regulatory Guide |
| RPV | reactor pressure vessel |
| RT | reference temperature |
| SBO | station blackout |
| SCC | stress corrosion cracking |
| SER | safety evaluation report |
| SG | steam generator |
| S/G | standards and guides |
| SOC | statement of considerations |
| SOER | significant operating experience report |
| SRM | staff requirements memorandum |
| SRP | standard review plan |
| SRP-LR | standard review plan for license renewal |
| SS | stainless steel |
| SSC | systems, structures, and components |
| SSE | safe shutdown earthquake |
| TLAA | time-limited aging analysis |
| UFSAR | updated final safety analysis report |
| USI | unresolved safety issue |
| UT | ultrasonic testing |
| UV | ultraviolet |
Introduction
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The Standard Review Plan for Review of License Renewal Applications for Nuclear Power Plants (SRP-LR) provides guidance to Nuclear Regulatory Commission (NRC) staff reviewers in the Office of Nuclear Reactor Regulation (NRR). These reviewers perform safety reviews of applications to renew nuclear power plant licenses in accordance with Title 10 of the Code of Federal Regulations (CFR) Part 54. The principal purposes of the SRP-LR are to ensure the quality and uniformity of staff reviews and to present a well-defined base from which to evaluate applicant programs and activities for the period of extended operation. The SRP-LR is also intended to make information about regulatory matters widely available, to enhance communication with interested members of the public and the nuclear power industry, and to improve their understanding of the staff review process.
The safety review is based primarily on the information provided by the applicant in a license renewal application. The NRC regulation, in 10 CFR 54.21, requires that each license renewal application shall include an integrated plant assessment (IPA), current licensing basis (CLB) changes during review of the application by NRC, an evaluation of time-limited aging analyses (TLAAs), and a final safety analysis report (FSAR) supplement.
In addition to the technical information required by 10 CFR 54.21, a license renewal application must contain general information (10 CFR 54.19), necessary technical specification changes (10 CFR 54.22), and environmental information (10 CFR 54.23). The application must be sufficiently detailed to permit the reviewers to determine (1) whether there is reasonable assurance that the activities authorized by the renewed license will continue to be conducted in accordance with the CLB and (2) whether any changes made to the plant's CLB to comply with 10 CFR Part 54 are in accord with the Atomic Energy Act of 1954 and NRC regulations.
Before submitting a license renewal application, an applicant should have analyzed the plant to ensure that actions have been or will be taken to (1) manage the effects of aging during the period of extended operation (this determination should be based on the functionality of structures and components that are within the scope of license renewal and that require an aging management review) and (2) evaluate TLAAs. The license renewal application is the principal document in which the applicant provides the information needed to understand the basis upon which this assurance can be made.
10 CFR 54.21 specifies, in general terms, the technical information to be supplied in the license renewal application. Regulatory Guide 1.188, "Standard Format and Content for Applications to Renew Nuclear Power Plant Operating Licenses," proposes to endorse the Nuclear Energy Institute (NEI) guidance in NEI 95-10, Rev. 3, "Industry Guideline for Implementing the Requirements of 10 CFR Part 54 -- The License Renewal Rule." NEI 95-10 provides guidance on the format and content of a license renewal application. The SRP-LR sections are keyed to the RG 1.188 Standard Format document; the sections are numbered according to the section numbers in that document.
During the review of the initial license renewal applications, NRC staff and the applicants have found that most of the programs to manage aging that are credited for license renewal are existing programs. In a staff paper (SECY 99-148), "Credit for Existing Programs for License Renewal," dated June 3, 1999, the staff described options and provided a recommendation for crediting existing programs to improve the efficiency of the license renewal process. In a staff requirements memorandum (SRM) dated August 27, 1999, the NRC approved the staff recommendation and directed the staff to focus the review guidance in the SRP-LR on areas where existing programs should be augmented for license renewal. Under the terms of the SRM, the SRP-LR would reference a "Generic Aging Lessons Learned" (GALL) report, which evaluates existing programs generically, to document (1) the conditions under which existing programs are considered adequate to manage identified aging effects without change and (2) the conditions under which existing programs should be augmented for this purpose.
The GALL report (NUREG-1801) should be treated as an approved topical report. The NRC reviewers should not repeat their review of a matter described in the GALL report, but should find an application acceptable with respect to such a matter when the application references the GALL report and the evaluation of the matter in the GALL report applies to the plant. However, reviewers should ensure that the material presented in the GALL report is applicable to the specific plant involved and that the applicants have identified specific programs as described and evaluated in the GALL report if they rely on the report for license renewal.
The SRP-LR is divided into four major chapters: (1) Administrative Information; (2) Scoping and Screening Methodology for Identifying Structures and Components Subject to Aging Management Review, and Implementation Results; (3) Aging Management Review Results; and (4) Time-Limited Aging Analyses. The appendices to the SRP-LR list branch technical positions. The SRP-LR addresses various site conditions and plant designs and provides complete procedures for all of the areas of review pertinent to each of the SRP-LR sections. For any specific application, NRC reviewers may select and emphasize particular aspects of each SRP-LR section, as appropriate for the application. In some cases, the major portion of the review of a plant program or activity may be done on a generic basis (with the owners' group of that plant type) rather than in the context of reviews of particular applications from utilities. In other cases, a plant program or activity may be sufficiently similar to that of a previous plant that a complete review of the program or activity is not needed. For these and similar reasons, reviewers need not carry out in detail all of the review steps listed in each SRP-LR section in the review of every application.
The individual SRP-LR sections address (1) who performs the review, (2) the matters that are reviewed, (3) the basis for review, (4) the way the review is accomplished, and (5) the conclusions that are sought. One of the objectives of the SRP-LR is to assign review responsibilities to the appropriate NRR branches. Each SRP-LR section identifies the branch that has the primary review responsibility for that section. In some review areas, the primary branch may require support; the branches that are assigned these secondary review responsibilities are also identified for each SRP-LR section.
Each SRP-LR section is organized into the following six subsections, generally consistent with NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants" (July 1981).
1. Areas of Review
This subsection describes the scope of review, that is, what is being reviewed by the branch that has primary review responsibility. It contains a description of the systems, structures, components, analyses, data, or other information that are reviewed as part of the license renewal application. It also contains a discussion of the information needed or the review expected from other branches to permit the primary review branch to complete its review.
2. Acceptance Criteria
This subsection contains a statement of the purpose of the review, an identification of applicable NRC requirements, and the technical basis for determining the acceptability of programs and activities within the area of review of the SRP-LR section. The technical bases consist of specific criteria, such as NRC regulatory guides, codes and standards, and branch technical positions.
Consistent with the approach described in NUREG-0800, the technical bases for some sections of the SRP-LR can be provided in branch technical positions or appendices as they are developed and can be included in the SRP-LR.
3. Review Procedures
This subsection discusses the way the review is accomplished. It is generally a step-by-step procedure that the reviewer follows to provide reasonable verification that the applicable acceptance criteria have been met.
4. Evaluation Findings
This subsection presents the type of conclusion that is sought for the particular review area. For each section, a conclusion of this type is included in the safety evaluation report (SER), in which the reviewers publish the results of their review. The SER also contains a description of the review, including which aspects of the review were selected or emphasized; which matters were modified by the applicant, required additional information, will be resolved in the future, or remain unresolved; where the applicant's program deviates from the criteria provided in the SRP-LR; and the bases for any deviations from the SRP-LR or exemptions from the regulations.
5. Implementation
This subsection discusses the NRC staff's plans for using the SRP-LR section.
6. References
This subsection lists the references used in the review process.
The SRP-LR incorporates the staff experience in the review of the initial license renewal applications. It may be considered a part of a continuing regulatory framework development activity that documents current methods of review and provides a basis for orderly modifications of the review process in the future. The SRP-LR will be revised and updated periodically, as needed, to incorporate experience gained during future reviews, to clarify the content or correct errors, to reflect changes in relevant regulations, and to incorporate modifications approved by the NRR Director. A revision number and publication date are printed in a lower corner of each page of each SRP-LR section. Because individual sections will be revised as needed, the revision numbers and dates will not be the same for all sections. The table of contents indicates the revision numbers of the most current sections. Comments and suggestions for improvement should be sent to the Director, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001. Notices of errors or omissions should be sent to the same address.
Chapter 1: Administrative Information
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1.1 Docketing of Timely and Sufficient Renewal Application
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Review Responsibilities
Primary - Branch responsible for license renewal projects
Secondary - Branch responsible for environmental review and branches responsible for technical review, as appropriate
1.1.1 Areas of Review
This section addresses (1) the review of the acceptability of a license renewal application for docketing in accordance with 10 CFR 2.101 and the requirements of 10 CFR Part 54 and (2) whether a license renewal application is timely and sufficient, which allows the provisions of 10 CFR 2.109(b) to apply. Allowing this regulation, which was written to comply with the Administrative Procedures Act, to apply to the application means that the current license will not expire until the NRC makes a final determination on the license renewal application.
The review described in this section is not a detailed, in-depth review of the technical aspects of the application. The docketing and finding of a timely and sufficient renewal application does not preclude the NRC reviewers from requesting additional information as the review proceeds, nor does it predict the NRC's final determination regarding the acceptance or rejection of the renewal application. A plant's current license will not expire after the passing of the license's expiration date if the renewal application was found to be timely and sufficient. During this time, and until the renewal application has been approved by the NRC, the licensee must continue to perform its activities in accordance with the facility's CLB, including all applicable license conditions, orders, rules, and regulations.
In determining whether an application is acceptable for docketing, the following areas of the license renewal application are reviewed.
1.1.1.1 Docketing and Sufficiency of Application
The license renewal application is reviewed for acceptability for docketing as a sufficient application in accordance with 10 CFR 2.101, 10 CFR Part 51, and 10 CFR Part 54.
1.1.1.2 Timeliness of Application
The timeliness of a license renewal application is reviewed in accordance with 10 CFR 2.109(b).
1.1.2 Acceptance Criteria
1.1.2.1 Docketing/Sufficiency of Application
NRC staff determine acceptance for docketing and sufficiency on the basis of the required contents of an application, established in 10 CFR 2.101, 10 CFR 51.53(c), 54.17, 54.19, 54.21, 54.22, and 54.23. A license renewal application is sufficient if it contains the reports, analyses, and other documents required in such an application.
1.1.2.2 Timeliness of Application
In accordance with 10 CFR 2.109(b), a license renewal application is timely if it is submitted at least 5 years before the expiration of the current operating license and it is determined to be sufficient.
1.1.3 Review Procedures
A licensee may choose to submit plant-specific reports addressing portions of the license renewal rule requirements for NRC review and approval prior to submitting a renewal application. An applicant may incorporate (by reference) these reports or other information contained in previous applications for licenses or license amendments, statements, or correspondence filed with the NRC, provided that the references are clear and specific. However, the final determination of the docketing of a sufficient renewal application is made only after a formal license renewal application has been submitted to the NRC.
For each area of review, NRC staff should implement the following review procedures.
1.1.3.1 Docketing and Sufficiency of Application
Upon receipt of a tendered application for license renewal, the reviewer should determine whether the applicant has made a reasonable effort to provide the required administrative, technical, and environmental information.(1) The reviewer should use the review checklist provided in Table 1.1-1 to determine whether the application is reasonably complete and conforms to the requirements outlined in 10 CFR Part 54.
Items I.1 through I.10 in the checklist address administrative information: for the purpose of this review, the reviewer should check the "Yes" column if the required information is included in the application. Item II in the checklist addresses timeliness of the application.
Items II.1 through II.3, III, and IV in the checklist address technical information, the FSAR supplement, and technical specification changes, respectively. Chapters 2, 3, and 4 of the SRP-LR provide information regarding the technical review. Although the purpose of the docketing and sufficiency review is not to determine the technical adequacy of the application, the reviewer should determine whether the applicant has provided reasonably complete information in the application to address the renewal rule requirements. The reviewer may request assistance from appropriate technical review branches to determine whether the application provides sufficient information to address the items in the checklist so that the staff can begin their technical review. The reviewer should check the "Yes" column for a checklist item if the applicant has provided reasonably complete information in the application to address the checklist item.
Item V of the checklist addresses environmental information. The environmental review staff should review the supplement to the environmental report prepared by the applicant in accordance with the guidelines in NUREG-1555, "Standard Review Plans for Environmental Reviews for Nuclear Power Plants," Supplement 1, "Operating License Renewal" (Ref. 2). The reviewer should check the "Yes" column if it is determined that the renewal application contains environmental information consistent with the requirements of 10 CFR Part 51.
The application should address each item in the checklist in order to be considered reasonably complete and sufficient. If the reviewer determines that an item in the checklist is not applicable, the reviewer should include a brief statement that the item is not applicable and provide the basis for the statement.
If information in the application for a checklist item is either not provided or not reasonably complete and no justification is provided, the reviewer should check the "No" column for that checklist item. By checking the "No" column for any checklist item, except Item VI as discussed in Subsection 1.1.3.2, the reviewer indicates that the application is not acceptable for docketing as a sufficient renewal application, unless the applicant modifies the application to provide the missing or incomplete information.
If the reviewer determines that the application is not acceptable for docketing as a sufficient application, the letter to the applicant should clearly state that (1) the application is not sufficient and is not acceptable for docketing and (2) the current license will expire at its expiration date. The letter should also include a description of the deficiencies found in the application and offer an opportunity for the applicant to modify its application to provide the missing or incomplete information. The reviewer should review the modified application, if submitted, to determine whether it is acceptable for docketing as a sufficient application.
If the reviewer is able to answer "Yes" to the applicable items in the checklist, the application is acceptable for docketing as a sufficient renewal application. The applicant should be notified by letter that the application is accepted for docketing. Normally, the letter should be issued within 30 days of receipt of a renewal application. A notice of acceptance for docketing of the application and notice of opportunity for a hearing regarding renewal of the license will be published in the Federal Register.
If the application is acceptable for docketing as a sufficient application, the staff should begin their technical review. For license renewal applications, the NRC intends to maintain the docket number of the current operating license for administrative convenience.
1.1.3.2 Timeliness of Application
Upon receipt of a tendered application for license renewal, the reviewer performs a docketing and sufficiency review, as discussed in Subsection 1.1.3.1.
If the sufficient application is submitted at least 5 years before the expiration of the current operating license, the reviewer checks the "Yes" column for Item VI in the checklist. If an applicant has to modify its application, as discussed in Subsection 1.1.3.1, before the staff can find the application acceptable for docketing as a sufficient application, the modified application should be submitted at least 5 years before the expiration of the current operating license.
If the reviewer checks the "No" column in Item VI in the checklist, indicating that a sufficient renewal application has not been submitted at least 5 years before the expiration of the current operating license, the letter to the applicant should clearly state that (1) the application is not timely, (2) the provisions in 10 CFR 2.109(b) have not been satisfied, and (3) the current license will expire on the expiration date. However, if the application is otherwise determined to be acceptable for docketing, the technical review can begin.
1.1.4 Evaluation Findings
The reviewer determines whether sufficient and adequate information has been
provided to satisfy the provisions outlined here. Depending on the results of
this review, one of the following conclusions is included in the staff's letter
to the applicant:
- The NRC staff has determined that the applicant has submitted sufficient
information that is acceptable for docketing, in accordance with 10 CFR
54.19, 54.21, 54.22, 54.23, and 51.53(c). However, the staff's determination
does not preclude the request for additional information as the review proceeds.
- The application is not acceptable for docketing as a timely and sufficient renewal application.
1.1.5 Implementation
Except in cases in which the applicant proposes an acceptable alternative method for complying with specified portions of NRC regulations, the method described herein will be used by NRC staff in their evaluation of conformance with NRC regulations.
1.1.6 References
1. NRC Regulatory Guide 1.188, "Standard Format and Content for Applications to Renew Nuclear Power Plant Operating Licenses," U.S. Nuclear Regulatory Commission, July 2001.
2. NUREG-1555, "Standard Review Plans for Environmental Reviews for Nuclear Power Plants," Supplement 1, "Operating License Renewal," U.S. Nuclear Regulatory Commission, October 1999.
Table 1.1-1. Acceptance Review Checklist for Docketing of Timely and Sufficient Renewal Application
Chapter 2: Scoping and Screening Methodology for Identifying Structures and Components Subject to Aging Management Review and Implementation Results
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2.1 Scoping and Screening Methodology
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Review Responsibilities
Primary - Branch responsible for quality assurance
Secondary - Branches responsible for systems, as appropriate
2.1.1 Areas of Review
This section addresses the scoping and screening methodology for license renewal. As required by 10 CFR 54.21(a)(2), the applicant, in its integrated plant assessment (IPA), is to describe and justify methods used to identify systems, structures, and components (SSCs) subject to an aging management review (AMR). The SSCs subject to AMR are those that perform an intended function, as described on 10 CFR 54.4 and meet two criteria:
1. They perform such functions without moving parts or without a change in configuration or properties, as set forth in 10 CFR 54.21(a)(1)(i), (denoted as "passive" components and structures in this SRP), and
2. They are not subject to replacement based on a qualified life or specified time period, as set forth in 10 CFR 54.21 (a)(1)(ii), (denoted as "long-lived" structures and components).
The identification of the SSCs within the scope of license renewal is called "scoping." For those SSCs within the scope of license renewal, the identification of "passive," "long-lived" structures and components that are subject to an AMR is called "screening."
To verify that the applicant has properly implemented its methodology, the staff reviews the implementation results separately, following the guidance in Sections 2.2 through 2.5.
The following areas relating to the applicant's scoping and screening methodology are reviewed.
2.1.1.1 Scoping
The methodology used by the applicant to implement the scoping requirements of 10 CFR 54.4, "Scope," is reviewed.
2.1.1.2 Screening
The methodology used by the applicant to implement the "screening" requirements of 10 CFR 54.21(a)(1) is reviewed.
2.1.2 Acceptance Criteria
The acceptance criteria for the areas of review are based on the following
regulations:
- 10 CFR 54.4(a) as it relates to the identification of plant SSCs within
the scope of the rule;
- 10 CFR 54.4(b) as it relates to the identification of the intended functions
of plant SSCs determined to be within the scope of the rule; and
- 10 CFR 54.21(a)(1) and (a)(2) as they relate to the methods used by the applicant to identify plant structures and components subject to an AMR.
Specific criteria necessary to determine whether the applicant has met the relevant requirements of 10 CFR 54.4(a), 54.4(b), 54.21(a)(1), and 54.21(a)(2) are as follows.
2.1.2.1 Scoping
The scoping methodology used by the applicant should be consistent with the process described in Section 3.0, "Identify the SSCs within the Scope of License Renewal and Their Intended Functions," of NEI 95-10, "Industry Guideline for Implementing the Requirements of 10 CFR Part 54 -- The License Renewal Rule," Rev. 3 (Ref. 1), or the justification provided by the applicant for any exceptions should be found to be acceptable by the reviewer.
2.1.2.2 Screening
The screening methodology used by the applicant should be consistent with the process described in Section 4.1, "Identification of Structures and Components Subject to an Aging Management Review and Intended Functions," of NEI 95-10, Rev. 3 (Ref. 1).
2.1.3 Review Procedures
Preparation for the review of the scoping and screening methodology employed
by the applicant should include the following:
- Review of the NRC's safety evaluation report (SER) that was issued upon receipt
of the operating license for the facility. This review is conducted for the
purpose of familiarization with the principal design criteria for the facility
and its CLB, as defined in 10 CFR 54.3(a).
- Review of Chapters 1 through 12 of the Updated Final Safety Analysis Report
(UFSAR) and the facility's technical specifications for the purposes of familiarization
with the facility design and the nomenclature that is applied to SSCs within
the facility (including the bases for such nomenclature). During this review,
the SSCs should be identified that are relied upon to remain functional during
and after design basis events (DBEs), as defined in 10 CFR 50.49(b)(1)(ii),
for which the facility was designed, to ensure that the functions described
in 10 CFR 54.4(a)(1) are successfully accomplished. This review should
also yield information regarding seismic Category I SSCs as defined in Regulatory
Guide 1.29, "Seismic Design Classification" (Ref. 2). For a newer plant,
this information is typically contained in Section 3.2.1, "Seismic Classification,"
of the UFSAR consistent with the Standard Review Plan (NUREG-0800) (Ref. 3).
- Review of Chapter 15 (or equivalent) of the UFSAR to identify the anticipated
operational occurrences and postulated accidents that are explicitly evaluated
in the accident analyses for the facility. During this review, the SSCs that
are relied upon to remain functional during and following design basis events
(as defined in 10 CFR 50.49(b)(1)) to ensure the functions described in 10 CFR
54.4(a)(1) should be identified.
- The set of design basis events as defined in the rule is not limited to Chapter
15 (or equivalent) of the UFSAR. Examples of design basis events that may not
be described in this chapter include external events, such as floods, storms,
earthquakes, tornadoes, or hurricanes, and internal events, such as a high-energy-line
break. Information regarding design basis events as defined in 10 CFR 50.49(b)(1)
may be found in any chapter of the facility UFSAR, the Commission's regulations,
NRC orders, exemptions, or license conditions within the CLB. These sources
should also be reviewed to identify systems, structures, and components that
are relied upon to remain functional during and following design basis events
(as defined in 10 CFR 50.49(b)(1)) to ensure the functions described in 10 CFR
54.4(a)(1).
- Review of the facility's Probabilistic Risk Analysis (PRA) Summary Report
that was prepared by the licensee in response to Generic Letter (GL) 88-20,
"Individual Plant Examination for Severe Accident Vulnerabilities - 10 CFR
50.54(f)," dated November 23, 1988 (Ref. 4). This review should yield additional
information regarding the impact of the Individual Plant Examination (IPE) on
the CLB for the facility. While the LR Rule is "deterministic," the NRC in the
statement of considerations (SOC) accompanying Rule also states: "In license renewal, probabilistic methods may be most useful, on a plant-specific
basis, in helping to assess the relative importance of structures and components
that are subject to an aging management review by helping to draw attention
to specific vulnerabilities (e.g., results of an IPE or IPEEE)" (60 FR
22468). For example, the reviewer should focus IPE information pertaining to
plant changes or modifications that are initiated by the licensee in accordance
with the requirements of 10 CFR 50.59 or 10 CFR 50.90.
- Review of the results of facility's Individual Plant Examination of External
Events (IPEEE) study conducted as a follow-up to the IPE performed as a result
of GL 88-20 to identify any changes or modifications made to the facility
in accordance with the requirements of 10 CFR 50.59 or 10 CFR 50.90.
- Review of the applicant's docketed correspondence related to the following regulations:
(a) 10 CFR 50.48, "Fire Protection,"
(b) 10 CFR 50.49, "Environmental Qualification of Electric Equipment Important to Safety for Nuclear Power Plants,"
(c) 10 CFR 50.61, "Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events,"
(d) 10 CFR 50.62, "Requirements for Reduction of Risk from Anticipated Transients without Scram Events for Light-Water-Cooled Nuclear Power Plants," and
(e) 10 CFR 50.63, "Loss of All Alternating Current Power" [applicable to pressurized water reactor (PWR) plants].
Other staff members are reviewing the applicant's scoping and screening results separately following the guidance in Sections 2.2 through 2.5. The reviewer should keep these other staff members informed of findings that may affect their review of the applicant's scoping and screening results. The reviewer should coordinate this sharing of information through the license renewal project manager.
2.1.3.1 Scoping
Once the information delineated above has been gathered, the reviewer reviews the applicant's methodology to determine whether its depth and breadth are sufficiently comprehensive to identify the SSCs within the scope of license renewal, and the structures and components requiring an AMR. Because "[t]he CLB represents the evolving set of requirements and commitments for a specific plant that are modified as necessary over the life of a plant to ensure continuation of an adequate level of safety" (60 FR 22465, May 8, 1995), the regulations, orders, license conditions, exemptions, and technical specifications defining functional requirements for facility SSCs that make up an applicant's CLB should be considered as the initial input into the scoping process. 10 CFR 50.49 defines DBEs as conditions of normal operation, including anticipated operational occurrences, DBAs, external events, and natural phenomena for which the plant must be designed to ensure (1) the integrity of the reactor pressure boundary, (2) the capability to shut down the reactor and maintain it in safe shutdown condition, or (3) the capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposures comparable to those referred to in 10 CFR 50.34(a)(1), 50.67(b)(2), or 100.11, as applicable. Therefore, to determine the safety-related SSCs that are within the scope of the rule under 10 CFR 54.4 (a)(1), the applicant must identify those SSCs that are relied upon to remain functional during and following these DBEs, consistent with the CLB of the facility. Most licensees have developed lists or database that identify systems, structures and components relied on for compliance with other regulations in a manner consistent with the CLB of their facilities. Consistent with the licensing process and regulatory criteria used to develop such lists or databases, licensees should build upon these information sources to satisfy 10 CFR Part 54 requirements.
With respect to technical specifications, the NRC states (60 FR 22467):
The Commission believes that there is sufficient experience with its policy on technical specifications to apply that policy generically in revising the license renewal rule consistent with the Commission's desire to credit existing regulatory programs. Therefore, the Commission concludes that the technical specification limiting conditions for operation scoping category is unwarranted and has deleted the requirement that identifies systems, structures, and components with operability requirements in technical specifications as being within the scope of the license renewal review.
Therefore, the applicant need not consider its technical specifications and applicable limiting conditions of operation when scoping for license renewal. This is not to say that the events and functions addressed within the applicant's technical specifications can be excluded in determining the SSCs within the scope of license renewal solely on the basis of such an event's inclusion in the technical specifications. Rather, those SSCs governed by an applicant's technical specifications that are relied upon to remain functional during a DBE, as identified within the applicant's UFSAR, applicable NRC regulations, license conditions, NRC orders, and exemptions, need to be included within the scope of license renewal.
For licensee commitments, such as licensee responses to NRC bulletins, generic letters, or enforcement actions, and those documented in staff safety evaluations or license event reports, and which make up the remainder of an applicant's CLB, many of the associated SSCs need not be considered under license renewal. Generic communications, safety evaluations, and other similar documents found on the docket are not regulatory requirements, and commitments made by a licensee to address any associated safety concerns are not typically considered to be design requirements. However, any generic communication, safety evaluation, or licensee commitment that specifically identifies or describes a function associated with a system, structure, or component necessary to fulfill the requirement of a particular regulation, order, license condition, and/or exemption may need to be considered when scoping for license renewal. For example, NRC Bulletin 88-11, "Pressurizer Surge Line Thermal Stratification," states:
The licensing basis according to 10 CFR 50.55a for all PWRs requires that the licensee meet the American Society of Mechanical Engineers Boiler and Pressure Vessel Code Sections III and XI and to reconcile the pipe stresses and fatigue evaluation when any significant differences are observed between measured data and the analytical results for the hypothesized conditions. Staff evaluation indicates that the thermal stratification phenomenon could occur in all PWR surge lines and may invalidate the analyses supporting the integrity of the surge line. The staff's concerns include unexpected bending and thermal striping (rapid oscillation of the thermal boundary interface along the piping inside surface) as they affect the overall integrity of the surge line for its design life (e.g., the increase of fatigue).
Therefore, this bulletin specifically describes conditions that may affect compliance with the requirements associated with 10 CFR 50.55a and functions specifically related to this regulation that must be considered in the scoping process for license renewal.
An applicant may take an approach in scoping and screening that combines similar components from various systems. For example, containment isolation valves from various systems may be identified as a single system for purposes of license renewal.
Staff from branches responsible for systems may be requested to assist in reviewing the plant design basis and intended function(s), as necessary.
The reviewer should verify that the applicant's scoping methods document the actual information sources used (for example, those identified in Table 2.1-1).
Table 2.1-2 contains specific staff guidance on certain subjects of scoping.
2.1.3.1.1 Safety-Related
The applicant's methodology is reviewed to ensure that the safety-related SSCs
are identified to satisfactorily accomplish any of the intended functions identified
in 10 CFR 54.4(a)(1). The reviewer must ascertain how, and to what extent,
the applicant incorporated the information in the CLB for the facility in its
methodology. Specifically, the reviewer should review the application, as well
as all other relevant sources of information outlined above, to identify the
set of plant-specific conditions of normal operation, DBAs, external events,
and natural phenomena for which the plant must be designed to ensure the following
functions:
- The integrity of the reactor coolant pressure boundary;
- The capability to shut down the reactor and maintain it in a safe shutdown
condition; or
- The capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposure comparable to the guidelines in 10 CFR 50.34(a)(1), 50.67(b)(2), or 100.11, as applicable.
2.1.3.1.2 Nonsafety-Related
The applicant's methodology is reviewed to ensure that nonsafety-related SSCs whose failure could prevent satisfactory accomplishment of any of the functions identified in 10 CFR 54.4(a)(1) are identified as being within the scope of license renewal.
The scoping criterion under 10 CFR 54.4(a)(2), in general, is intended to identify those nonsafety-related SSCs that support safety-related functions. More specifically, this scoping criterion requires an applicant to identify all nonsafety-related SSCs whose failure could prevent satisfactory accomplishment of the applicable functions of the SSCs identified under 10 CFR 54.4(a)(1). Section III.c(iii) of the SOC (60 FR 22467) clarifies the NRC's intent for this requirement in the following statement:
The inclusion of nonsafety-related systems, structures, and components whose failure could prevent other systems, structures, and components from accomplishing a safety function is intended to provide protection against safety function failure in cases where the safety-related structure or component is not itself impaired by age-related degradation but is vulnerable to failure from the failure of another structure or component that may be so impaired.
In addition, Section III.c(iii) of the SOC provides the following guidance to assist an applicant in determining the extent to which failures must be considered when applying this scoping criterion:
Consideration of hypothetical failures that could result from system interdependencies that are not part of the current licensing bases and that have not been previously experienced is not required. [...] However, for some license renewal applicants, the Commission cannot exclude the possibility that hypothetical failures that are part of the CLB may require consideration of second-, third-, or fourth-level support systems.
Therefore, to satisfy the scoping criterion under 10 CFR 54.4(a)(2), the applicant must identify those nonsafety-related SSCs (including certain second-, third-, or fourth-level support systems) whose failures are considered in the CLB and could prevent the satisfactory accomplishment of the safety-related function identified under 10 CFR 54.4(a)(1). In order to identify such systems, the applicant should consider those failures identified in (1) the documentation that makes up its CLB, (2) plant-specific operating experience, and (3) industry-wide operating experience that is specifically applicable to its facility. The applicant need not consider hypothetical failures that are not part of the CLB, have not been previously experienced, or are not applicable to its facility.
For example, the safety classification of a pipe at certain locations, such as valves, may change throughout its length in the plant. In these instances, the applicant should identify the safety-related portion of the pipe as being within the scope of license renewal under 10 CFR 54.4(a)(1). However, the entire pipe run, including associated piping anchors, may have been analyzed as part of the CLB to establish that it could withstand DBE loads. If this is the case, a failure in the pipe run or in the associated piping anchors could render the safety-related portion of the piping unable to perform its intended function under CLB design conditions. Therefore, the reviewer must verify that the applicant's methodology would include (1) the remaining nonsafety-related piping up to its anchors and (2) the associated piping anchors as being within the scope of license renewal under 10 CFR 54.4(a)(2).
It is important to note that the scoping criterion under 10 CFR 54.4(a)(2) specifically applies to those functions "identified in paragraphs (a)(1)(i), (ii), and (iii)" of 10 CFR 54.4 and does not apply to functions identified in 10 CFR 54.4(a)(3), as discussed below.
2.1.3.1.3 "Regulated Events"
The applicant's methodology is reviewed to ensure that SSCs relied on in safety analyses or plant evaluations to perform functions that demonstrate compliance with the requirements of the fire protection, environmental qualification, pressurized thermal shock (PTS), anticipated transients without scram (ATWS), and station blackout (SBO) regulations are identified. The reviewer should review the applicant's docketed correspondence associated with compliance of the facility with these regulations.
The scoping criteria in 10 CFR 54.4(a)(3) require an applicant to consider "[a]ll SSC relied on in safety analyses or plant evaluations to perform a function that demonstrates compliance with the [specified] Commission regulations[.]" In addition, Section III.c(iii) (60 FR 22467) of the SOC states that the NRC intended to limit the potential for unnecessary expansion of the review for SSCs that meet the scoping criteria under 10 CFR 54.4(a)(3) and provides additional guidance that qualifies what is meant by "those SSCs relied on in safety analyses or plant evaluations to perform a function that demonstrates compliance with the Commission regulations" in the following statement:
[T]he Commission intends that this [referring to 10 CFR 54.4(a)(3)] scoping category include all SSC whose function is relied upon to demonstrate compliance with these Commission[ ] regulations. An applicant for license renewal should rely on the plant's current licensing bases, actual plant-specific experience, industry-wide operating experience, as appropriate, and existing engineering evaluations to determine those SSC that are the initial focus of license renewal review.
Therefore, all SSCs that are relied upon in the plant's CLB (as defined in 10 CFR 54.3), plant-specific experience, industry-wide experience (as appropriate), and safety analyses or plant evaluations to perform a function that demonstrates compliance with NRC regulations identified under 10 CFR 54.4(a)(3), are required to be included within the scope of the rule. For example, if a nonsafety-related diesel generator is required for safe shutdown under the fire protection plan, the diesel generator and all SSCs specifically required for that generator to comply with and NRC regulations shall be included within the scope of license renewal under 10 CFR 54.4(a)(3). Such SSCs may include, but should not be limited to, the cooling water system or systems required for operability, the diesel support pedestal, and any applicable power supply cable specifically required for safe shutdown in the event of a fire.
In addition, the last sentence of the second paragraph in Section III.c(iii) of the SOC provides the following guidance for limiting the application of the scoping criteria under 10 CFR 54.4(a)(3) as it applies to the use of hypothetical failures:
Consideration of hypothetical failures that could result from system interdependencies, that are not part of the current licensing bases and that have not been previously experienced is not required. (60 FR 22467)
The SOC does not provide any additional guidance relating to the use of hypothetical failures or the need to consider second-, third-, or fourth-level support systems for scoping under 10 CFR 54.4(a)(3). Therefore, in the absence of any guidance, an applicant need not consider hypothetical failures or second-, third-, or fourth-level support systems in determining the SSCs within the scope of the rule under 10 CFR 54.4(a)(3). For example, if a nonsafety-related diesel generator is relied upon only to remain functional to demonstrate compliance with the NRC SBO regulations, the applicant need not consider the following SSCs: (1) an alternate/backup cooling water system, (2) non-seismically-qualified building walls, or (3) an overhead segment of non-seismically-qualified piping (in a Seismic II/I configuration). This guidance is not intended to exclude any support system (whether identified by an applicant's CLB, or as indicated from actual plant-specific experience, industrywide experience [as applicable], safety analyses, or plant evaluations) that is specifically required for compliance with, the applicable NRC regulation. For example, if a nonsafety-related diesel generator (required to demonstrate compliance with an applicable NRC regulation) specifically requires a second cooling system to cool the diesel generator jacket water cooling system for the generator to be operable, then both cooling systems must be included within the scope of the rule under 10 CFR 54.4(a)(3).
The applicant is required to identify the SSCs whose functions are relied on to demonstrate compliance with the regulations identified in 10 CFR 54.4(a)(3) (that is, whose functions were credited in the analysis or evaluation). Mere mention of an SSC in the analysis or evaluation does not necessarily constitute support of an intended function as required by the regulation.
For environmental qualification, the reviewer verifies that the applicant has indicated that the environmental qualification equipment is that equipment already identified by the licensee under 10 CFR 50.49(b), that is, equipment relied upon in safety analyses or plant evaluations to demonstrate compliance with NRC regulations for environmental qualification (10 CFR 50.49).
The PTS regulation is applicable only to PWRs. If the renewal application is for a PWR and the applicant relies on a Regulatory Guide 1.154 (Ref. 5) analysis to satisfy 10 CFR 50.61, as described in the plant's CLB, the reviewer verifies that the applicant's methodology would include SSCs relied on in that analysis that are within the scope of license renewal.
For SBO, the reviewer verifies that the applicant's methodology would include those SSCs relied upon during the "coping duration" phase of an SBO event (Ref. 6).
2.1.3.2 Screening
Once the SSCs within the scope of license renewal have been identified, the next step is determining which structures and components are subject to an AMR (i.e., "screening") (Ref. 1).
2.1.3.2.1 "Passive"
The reviewer reviews the applicant's methodology to ensure that "passive" structures and components are identified as those that perform their intended functions without moving parts or a change in configuration or properties in accordance with 10 CFR 54.21(a)(1)(i). The description of "passive" may also be interpreted to include structures and components that do not display "a change in state." 10 CFR 54.21(a)(1)(i) provides specific examples of structures and components that do or do not meet the criterion. The reviewer verifies that the applicant's screening methodology includes consideration of the intended functions of structures and components consistent with plant CLB, as typified in Table 2.1-4 (Ref. 1).
The license renewal rule focuses on "passive" structures and components because structures and components that have passive functions generally do not have performance and condition characteristics that are as readily observable as those that perform active functions. "Passive" structures and components, for the purpose of the license renewal rule, are those that perform an intended function, as described in 10 FR 54.4, without moving parts or without a change in configuration or properties (Ref. 2). The description of "passive" may also be interpreted to include structures and components that do not display "a change of state."
Table 2.1-5 provides a list of typical structures and components identifying whether they meet 10 CFR 54.21(a)(1)(i).
10 CFR 54.21(a)(1)(i) explicitly excludes instrumentation, such as pressure transmitters, pressure indicators, and water level indicators, from an AMR. The applicant does not have to identify pressure-retaining boundaries of this instrumentation because 10 CFR 54.21(a)(1)(i) excludes this instrumentation without exception, unlike pumps and valves. Further, instrumentation is sensitive equipment and degradation of its pressure retaining boundary would be readily determinable by surveillance and testing (Ref.6). If an applicant determines that certain structures and components listed in Table 2.1-5 as meeting 10 CFR 54.21(a)(1)(i) do not meet that requirement for its plant, the reviewer reviews the applicant's basis for that determination.
2.1.3.2.2 "Long-Lived"
The applicant's methodology is reviewed to ensure that "long-lived" structures and components are identified as those that are not subject to periodic replacement based on a qualified life or specified time period. Passive structures and components that are not replaced on the basis of a qualified life or specified time period require an AMR.
Replacement programs may be based on vendor recommendations, plant experience, or any means that establishes a specific replacement frequency under a controlled program. Section f(i)(b) of the SOC provides the following guidance for identifying "long-lived" structures and components:
In sum, a structure or component that is not replaced either (i) on a specified interval based upon the qualified life of the structure or component or (ii) periodically in accordance with a specified time period is deemed by §54.21(a)(1)(ii) of this rule to be "long-lived," and therefore subject to the §54.21(a)(3)[AMR][22478].
A qualified life does not necessarily have to be based on calendar time. A qualified life based on run time or cycles are examples of qualified life references that are not based on calendar time (Ref. 3).
Structures and components that are replaced on the basis of performance or condition are not generically excluded from an AMR. Rather, performance or condition monitoring may be evaluated later in the IPA as programs to ensure functionality during the period of extended operation. On this topic, Section f(i)(b) of the SOC provides the following guidance:
It is important to note, however, that the Commission has decided not to generically exclude passive structures and components that are replaced based on performance or condition from an [AMR]. Absent the specific nature of the performance or condition replacement criteria and the fact that the Commission has determined that the components with "passive" functions are not as readily monitorable as components with active functions, such generic exclusion is not appropriate. However, the Commission does not intend to preclude a license renewal applicant from providing site-specific justification in a license renewal application that a replacement program on the basis of performance or condition for a passive structure or component provides reasonable assurance that the intended function of the passive structure or component will be maintained in the period of extended operation. [ 60 FR 22478]
2.1.4 Evaluation Findings
When the review of the information in the license renewal application is complete, and the reviewer has determined that it is satisfactory and in accordance with the acceptance criteria in Subsection 2.1.2, a statement of the following type should be included in the staff's safety evaluation report:
The staff concludes that there is reasonable assurance that the applicant's methodology for identifying the systems, structures, and components within the scope of license renewal and the structures and components requiring an aging management review is consistent with the requirements of 10 CFR 54.4 and 10 CFR 54.21(a)(1).
2.1.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specified portions of NRC regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
2.1.6 References
1. NEI 95-10, Rev. 3 "Industry Guideline for Implementing the Requirements of 10 CFR Part 54 - The License Renewal Rule," Nuclear Energy Institute, March 2001.
2. Regulatory Guide 1.29, Rev. 2, "Seismic Design Classification," September 1978.
3. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants," July 1981.
4. Generic Letter (GL) 88-20, "Individual Plant Examination for Severe Accident Vulnerabilities- 10 CFR 50.54(f)," dated November 23, 1988.
5. Regulatory Guide 1.154, "Format and Content of Plant-Specific Pressurized Thermal Shock Safety Analysis Reports for Pressurized Water Reactors," January 1987.
6. Letter from Dennis M. Crutchfield of NRC to Charles H. Cruse of Baltimore Gas and Electric Company, dated April 4, 1996.
7. NUREG-1723, "Safety Evaluation Report Related to the License Renewal of Oconee Nuclear Stations, Units 1, 2, and 3," March 2000.
8. Letter to Douglas J. Walters, Nuclear Energy Institute, from Christopher I. Grimes, NRC, dated August 5, 1999.
9. Summary of December 8, 1999, Meeting with the Nuclear Energy Institute (NEI) on License Renewal Issue (LR) 98-12, "Consumables," Project No. 690, January 21, 2000.
10. Letter to William R. McCollum, Jr., Duke Energy Corporation, from Christopher I. Grimes, NRC, dated October 8,1999.
11. NEI 95-10, Rev. 0, "Industry Guideline for Implementing the Requirements of 10 CFR Part 54 - The License Renewal Rule," Nuclear Energy Institute, March 1, 1996.
Table 2.1-1. Sample Listing of Potential Information Sources
Verified databases (databases that are subject to administrative controls to assure and maintain the integrity of the stored data or information) Master equipment lists (including NSSS vendor listings) Q-lists Updated Final Safety Analysis Reports Piping and instrument diagrams NRC Orders, Exemptions, or License Conditions for the facility Design-basis documents General arrangement or structural outline drawings Probabilistic risk assessment summary report Maintenance rule compliance documentation Design-basis event evaluations (including plant-specific 10 CFR 50.59 evaluation procedures) Emergency operating procedures Docketed correspondence System interaction commitments Technical specifications Environmental qualification program documents Regulatory compliance reports (including Safety Evaluation Reports) Severe Accident Management Guidelines |
Table 2.1-2. Specific Staff Guidance on Scoping
| Issue | Guidance |
|---|---|
| Commodity groups | The applicant may also group like structures and components into commodity groups. Examples of commodity groups are pipe supports and cable trays. The basis for grouping structures and components can be determined by such characteristics as similar function, similar design, similar materials of construction, similar aging management practices, or similar environments. If the applicant uses commodity groups, the reviewer verifies that the applicant has described the basis for the groups. |
| Complex assemblies | Some structures and components, when combined, are considered a complex
assembly (for example, diesel generator starting air skids or heating, ventilating,
and air conditioning refrigerant units). For purposes of performing an AMR,
it is important to clearly establish the boundaries of review. An applicant
should establish the boundaries for such assemblies by identifying each structure
and component that makes up the complex assembly and determining whether or
not each structure and component is subject to an AMR (Ref. 1).
NEI 95-10, Revision 0, Appendix C, Example 5 (Ref. 11), illustrates how the evaluation boundary for a control room chiller complex assembly might be determined. The control room chillers were purchased as skid mounted equipment. These chillers are part of the control room chilled water system. There are two (2) control room chillers. Each is a 100% capacity refrigeration unit. The functions of the control room chillers are: to provide a reliable source of chilled water at a maximum temperature of 44oF, to provide a pressure boundary for the control room chilled water system, to provide a pressure boundary for the service water system, and to provide a pressure boundary for the refrigerant. All of these functions are considered intended functions. Typically, control room chillers are considered as one functional unit; however, for purposes of evaluating the effects of aging, it is necessary to consider the individual components. Therefore, the boundary of each control room chiller is established as follows: 1. At the inlet and outlet flanges of the service water system connections on the control room chiller condenser. Connected piping is part of the service water system. 2. At the inlet and outlet flanges of the control room chilled water system piping connections on the control room chiller evaporator. Connected piping is part of the control room chilled water system. 3. For electrical power supplies, the boundary is the output terminals on the circuit breakers supplying power to the skid. This includes the cables from the circuit breaker to the skid and applies for 480 VAC and 120 VAC. 4. The interface for instrument air supplies is at the instrument air tubing connection to the pressure control regulators, temperature controllers and transmitters, and solenoid valves located on the skid. The tubing from the instrument air header to the device on the skid is part of the instrument air system. 5. The interface with the annunciator system is at the external connection of the contacts of the device on the skid (limit switch, pressure switch, level switch, etc.) that indicates the alarm condition. The cables are part of the annunciator system. Based on the boundary established, the following components would be subject to an aging management review: condenser, evaporator, economizer, chiller refrigerant piping, refrigerant expansion orifice, foundations and bolting, electrical cabinets, cables, conduit, trays and supports, valves |
Table 2.1-2. Specific Staff Guidance on Scoping (continued)
| Issue | Guidance |
|---|---|
| Hypothetical failures | For 10 CFR 54.4(a)(2), an applicant should consider those failures
identified in (1) the documentation that makes up its CLB, (2) plant-specific
operating experience, and (3) industry-wide operating experience that is specifically
applicable to its facility. The applicant need not consider hypothetical failures
that are not part of CLB and that have not been previously experienced.
For example, an applicant should consider including (1) the portion of a fire protection system identified in the UFSAR that supplies water to the refueling floor that is relied upon in a DBA analysis as an alternate source of cooling water that can be used to mitigate the consequences from the loss of spent fuel pool cooling, (2) a nonsafety-related, non-seismically-qualified building whose intended function as described in the plant's CLB is to protect a tank that is relied upon as an alternate source of cooling water needed to mitigate the consequences of a DBE, and (3) a segment of nonsafety-related piping identified as a Seismic II/I component in the applicant's CLB (Ref. 8). |
| Cascading | For 10 CFR 54.4(a)(3), an applicant need not consider hypothetical failures or second-, third, or fourth-level support systems. For example, if a nonsafety-related diesel generator is only relied upon to remain functional to demonstrate compliance with the NRC's SBO regulations, an applicant may not need to consider (1) an alternate/backup cooling water system, (2) the diesel generator non-seismically-qualified building walls, or (3) an overhead segment of non-seismically-qualified piping (in a Seismic II/I configuration). An applicant may not exclude any support system (identified by its CLB, actual plant-specific experience, industry-wide experience, as applicable, or existing engineering evaluations) that is specifically required for compliance with, or operation within, applicable NRC regulation. For example, if the analysis of a nonsafety-related diesel generator (required to demonstrate compliance with an applicable NRC regulation) specifically requires a second cooling system to cool the diesel generator jacket water cooling system for the diesel to be operable, then both cooling systems must be included within the scope of the rule (Ref. 8). |
Table 2.1-3. Specific Staff Guidance on Screening
| Issue | Guidance |
|---|---|
| Consumables | Consumables may be divided into the following four categories for the purpose of license renewal: (a) packing, gaskets, component seals, and O-rings; (b) structural sealants; (c) oil, grease, and component filters; and (d) system filters, fire extinguishers, fire hoses, and air packs. The consumables in both categories (a) and (b) are considered as subcomponents and are not explicitly called out in the scoping and screening procedures. Rather, they are implicitly included at the component level (e.g., if a valve is identified as being in scope, a seal in that valve would also be in scope as a subcomponent of that valve). For category (a), the applicant would be able to exclude these subcomponents using a clear basis, such as the example of ASME Section III not being relied on for pressure boundary. For category (b), these subcomponents may perform functions without moving parts or a change in configuration, and they are not typically replaced. It is expected that the applicant's structural AMP will address these items with respect to an AMR program on a plant-specific basis. The consumables in category (c) are short-lived and periodically replaced, and can be excluded from an AMR on that basis. Likewise, the consumables that fall within category (d) are typically replaced based on performance or condition monitoring that identifies whether these components are at the end of their qualified lives and may be excluded, on a plant-specific basis, from AMR under 10 CFR 54.21(a)(1)(ii). The applicant should identify the standards that are relied on for the replacement as part of the methodology description (for example, NFPA standards for fire protection equipment) (Ref. 9). |
| Heat exchanger intended functions | Both the pressure boundary and heat transfer functions for heat exchangers should be considered because heat transfer may be a primary safety function of these components. There may be a unique aging effect associated with different materials in the heat exchanger parts that are associated with the heat transfer function and not the pressure boundary function. The staff would expect that the programs that effectively manage aging effects of the pressure boundary function can, in conjunction with the procedures for monitoring heat exchanger performance, effectively manage aging effects applicable to the heat transfer function (Ref. 10). |
| Multiple functions | Structures and components may have multiple functions. The intended functions as delineated in 10 CFR 54.4(b) are to be reviewed for license renewal. For example, a flow orifice that is credited in a plant's accident analysis to limit flow would have two intended functions. One intended function is pressure boundary. The other intended function is to limit flow. The reviewer verifies that the applicant has considered multiple functions in identifying structure and component intended functions. |
Table 2.1-4. Typical "Passive" Structure and Component Intended Functions
| Structures |
|---|
| Provide rated fire barrier to confine or retard a fire from spreading to or from adjacent areas of the plant |
| Provide shelter/protection to safety-related components |
| Provide structural and/or functional support to safety-related equipment |
| Provide flood protection barrier (internal and external flooding event) |
| Provide pressure boundary or essentially leaktight barrier to protect public health and safety in the event of any postulated design-basis events. |
| Provide spray shield or curbs for directing flow (e.g., safety injection flow to containment sump) |
| Provide shielding against radiation |
| Provide missile barrier (internally or externally generated) |
| Provide shielding against high-energy line breaks |
| Provide structural support to nonsafety-related components whose failure could prevent satisfactory accomplishment of any of the required safety-related functions |
| Provide pipe whip restraint |
| Provide path for release of filtered and unfiltered gaseous discharge |
| Provide source of cooling water for plant shutdown |
| Provide heat sink during station blackout or design-basis accidents |
| Components |
| Provide pressure-retaining boundary so that sufficient flow at adequate pressure is delivered |
| Provide filtration |
| Provide flow restriction (throttle) |
| Provide structural support to safety-related components |
| Provide electrical connections to specified sections of an electrical circuit to deliver voltage, current or signals |
| Provide heat transfer |
Table 2.1-5. Typical Structures, Components, and Commodity Groups, and 10 CFR 54.21(a)(1)(i) Determinations for Integrated Plant Assessment
| Item | Category | Structure, Component, or Commodity Grouping |
Structure, Component, or Commodity Group Meets 10 CFR 54.21(a)(1)(i) (Yes/No) |
|---|---|---|---|
| 1 | Structures | Category I Structures | Yes |
| 2 | Structures | Primary Containment Structure | Yes |
| 3 | Structures | Intake Structures | Yes |
| 4 | Structures | Intake Canal | Yes |
| 5 | Structures | Other Non-Category I Structures Within the Scope of License Renewal | Yes |
| 6 | Structures | Equipment Supports and Foundations | Yes |
| 7 | Structures | Structural Bellows | Yes |
| 8 | Structures | Controlled Leakage Doors | Yes |
| 9 | Structures | Penetration Seals | Yes |
| 10 | Structures | Compressible Joints and Seals | Yes |
| 11 | Structures | Fuel Pool and Sump Liners | Yes |
| 12 | Structures | Concrete Curbs | Yes |
| 13 | Structures | Offgas Stack and Flue | Yes |
| 14 | Structures | Fire Barriers | Yes |
| 15 | Structures | Pipe Whip Restraints and Jet Impingement Shields | Yes |
| 16 | Structures | Electrical and Instrumentation and Control Penetration Assemblies | Yes |
| 17 | Structures | Instrumentation Racks, Frames, Panels, and Enclosures | Yes |
| 18 | Structures | Electrical Panels, Racks, Cabinets, and Other Enclosures | Yes |
| 19 | Structures | Cable Trays and Supports | Yes |
| 20 | Structures | Conduit | Yes |
| 21 | Structures | Tube Track | Yes |
| 22 | Structures | Reactor Vessel Internals | Yes |
| 23 | Structures | ASME Class 1 Hangers and Supports | Yes |
| 24 | Structures | Non-ASME Class 1 Hangers and Supports | Yes |
| 25 | Structures | Snubbers | No |
| 26 | Reactor Coolant Pressure Boundary Components
(Note: the components of the RCPB are defined by each plant's CLB and site specific documentation |
ASME Class 1 Piping | Yes |
| 27 | Reactor Coolant Pressure Boundary Components | Reactor Vessel | Yes |
| 28 | Reactor Coolant Pressure Boundary Components | Reactor Coolant Pumps | Yes (Casing) |
Table 2.1-5. Typical Structures, Components, and Commodity
Groups, and
10 CFR 54.21(a)(1)(i) Determinations for Integrated Plant Assessment
(continued)
| Item | Category | Structure, Component, or Commodity Grouping |
Structure, Component, or Commodity Group Meets 10 CFR 54.21(a)(1)(i) (Yes/No) |
|---|---|---|---|
| 29 | Reactor Coolant Pressure Boundary Components | Control Rod Drives | No |
| 30 | Reactor Coolant Pressure Boundary Components | Control Rod Drive Housing | Yes |
| 31 | Reactor Coolant Pressure Boundary Components | Steam Generators | Yes |
| 32 | Reactor Coolant Pressure Boundary Components | Pressurizers | Yes |
| 33 | Non-Class I Piping Components | Underground Piping | Yes |
| 34 | Non-Class I Piping Components | Piping in Low Temperature Demineralized Water Service | Yes |
| 35 | Non-Class I Piping Components | Piping in High Temperature Single Phase Service | Yes |
| 36 | Non-Class I Piping Components | Piping in Multiple Phase Service | Yes |
| 37 | Non-Class I Piping Components | Service Water Piping | Yes |
| 38 | Non-Class I Piping Components | Low Temperature Gas Transport Piping | Yes |
| 39 | Non-Class I Piping Components | Stainless Steel Tubing | Yes |
| 40 | Non-Class I Piping Components | Instrument Tubing | Yes |
| 41 | Non-Class I Piping Components | Expansion Joints | Yes |
| 42 | Non-Class I Piping Components | Ductwork | Yes |
| 43 | Non-Class I Piping Components | Sprinklers Heads | Yes |
| 44 | Non-Class I Piping Components | Miscellaneous Appurtenances (Includes fittings, couplings, reducers, elbows, thermowells, flanges, fasteners, welded attachments, etc.) | Yes |
| 45 | Pumps | ECCS Pumps | Yes (Casing) |
| 46 | Pumps | Service Water and Fire Pumps | Yes (Casing) |
| 47 | Pumps | Lube Oil and Closed Cooling Water Pumps | Yes (Casing) |
| 48 | Pumps | Condensate Pumps | Yes (Casing) |
| 49 | Pumps | Borated Water Pumps | Yes (Casing) |
| 50 | Pumps | Emergency Service Water Pumps | Yes (Casing) |
| 51 | Pumps | Submersible Pumps | Yes (Casing) |
| 52 | Turbines | Turbine Pump Drives (excluding pumps) | Yes (Casing) |
| 53 | Turbines | Gas Turbines | Yes (Casing) |
| 54 | Turbines | Controls (Actuator and Overspeed Trip) | No |
| 55 | Engines | Fire Pump Diesel Engines | No |
| 56 | Emergency Diesel Generators | Emergency Diesel Generators | No |
| 57 | Heat Exchangers | Condensers | Yes |
| 58 | Heat Exchangers | HVAC Coolers | Yes |
| 59 | Heat Exchangers | Primary Water System Heat Exchangers | Yes |
| 60 | Heat Exchangers | Treated Water System Heat Exchangers | Yes |
| 61 | Heat Exchangers | Closed Cooling Water System Heat Exchangers | Yes |
| 62 | Heat Exchangers | Lubricating Oil System Heat Exchangers | Yes |
| 63 | Heat Exchangers | Raw Water System Heat Exchangers | Yes |
| 64 | Heat Exchangers | Containment Atmospheric System Heat Exchangers | Yes |
| 65 | Miscellaneous Process Components | Gland Seal Blower | No |
| 66 | Miscellaneous Process Components | Recombiners | The applicant shall identify the intended function and apply the IPA process to determine if the grouping is active or passive. |
| 67 | Miscellaneous Process Components | Flexible Connectors | Yes |
| 68 | Miscellaneous Process Components | Strainers | Yes |
| 69 | Miscellaneous Process Components | Rupture Disks | Yes |
| 70 | Miscellaneous Process Components | Steam Traps | Yes |
| 71 | Miscellaneous Process Components | Restricting Orifices | Yes |
| 72 | Miscellaneous Process Components | Air Compressor | No |
| 73 | Electrical and I&C | Alarm Unit
(e.g., fire detection devices) |
No |
| 74 | Electrical and I&C | Analyzers
(e.g., gas analyzers, conductivity analyzers) |
No |
| 75 | Electrical and I&C | Annunciators (e.g., lights, buzzers, alarms) | No |
| 76 | Electrical and I&C | Batteries | No |
| 77 | Electrical and I&C | Cables and Connections, Bus, electrical portions of Electrical and I&C
Penetration Assemblies
(e.g., electrical penetration assembly cables and connections, connectors, electrical splices, terminal blocks, power cables, control cables, instrument cables, insulated cables, communication cables, uninsulated ground conductors, transmission conductors, isolated-phase bus, nonsegregated-phase bus, segregated-phase bus, switchyard bus) |
Yes |
| 78 | Electrical and I&C | Chargers, Converters, Inverters
(e.g., converters-voltage/current, converters-voltage/pneumatic, battery chargers/inverters, motor-generator sets) |
No |
| 79 | Electrical and I&C | Circuit Breakers
(e.g., air circuit breakers, molded case circuit breakers, oil-filled circuit breakers) |
No |
| 80 | Electrical and I&C | Communication Equipment
(e.g., telephones, video or audio recording or playback equipment, intercoms, computer terminals, electronic messaging, radios, transmission line traps and other power-line carrier equipment) |
No |
| 81 | Electrical and I&C | Electric Heaters | No
Yes for a Pressure Boundary if applicable |
| Electrical and I&C | Heat Tracing | No | |
| 83 | Electrical and I&C | Electrical Controls and Panel Internal Component Assemblies (may include
internal devices such as, but not limited to, switches, breakers, indicating
lights, etc.)
(e.g., main control board, HVAC control board) |
No |
| 84 | Electrical and I&C | Elements, RTDs, Sensors, Thermocouples, Transducers
(e.g., conductivity elements, flow elements, temperature sensors, radiation sensors,watt transducers, thermocouples, RTDs, vibration probes, amp transducers, frequency transducers, power factor transducers, speed transducers, var. transducers, vibration transducers, voltage transducers) |
No
Yes for a Pressure Boundary if applicable |
| 85 | Electrical and I&C | Fuses | No |
| 86 | Electrical and I&C | Generators, Motors
(e.g., emergency diesel generators, ECCS and emergency service water pump motors, small motors, motor-generator sets, steam turbine generators, combustion turbine generators, fan motors, pump motors, valve motors, air compressor motors) |
No |
| 87 | Electrical and I&C | High-voltage Insulators
(e.g., porcelain switchyard insulators, transmission line insulators) |
Yes |
| 88 | Electrical and I&C | Surge Arresters
(e.g., switchyard surge arresters, lightning arresters, surge suppressers, surge capacitors, protective capacitors) |
No |
| 89 | Electrical and I&C | Indicators
(e.g., differential pressure indicators, pressure indicators, flow indicators, level indicators, speed indicators, temperature indicators, analog indicators, digital indicators, LED bar graph indicators, LCD indicators) |
No |
| 90 | Electrical and I&C | Isolators
(e.g., transformer isolators, optical isolators, isolation relays, isolating transfer diodes) |
No |
| 91 | Electrical and I&C | Light Bulbs
(e.g., indicating lights, emergency lighting, incandescent light bulbs, fluorescent light bulbs) |
No
|
| 92 | Electrical and I&C | Loop Controllers
(e.g., differential pressure indicating controllers, flow indicating controllers, temperature controllers, controllers, speed controllers, programmable logic controller, single loop digital controller, process controllers, manual loader, selector station, hand/auto station, auto/manual station) |
No |
| 93 | Electrical and I&C | Meters
(e.g., ammeters, volt meters, frequency meters, var meters, watt meters, power factor meters, watt-hour meters) |
No |
| 94 | Electrical and I&C | Power Supplies | No |
| 95 | Electrical and I&C | Radiation Monitors
(e.g., area radiation monitors, process radiation monitors) |
No |
| 96 | Electrical and I&C | Recorders
(e.g., chart recorders, digital recorders, events recorders) |
No |
| 97 | Electrical and I&C | Regulators (e.g., voltage regulators) | No |
| 98 | Electrical and I&C | Relays
(e.g., protective relays, control/logic relays, auxiliary relays) |
No |
| 99 | Electrical and I&C | Signal Conditioners | No |
| 100 | Electrical and I&C | Solenoid Operators | No |
| 101 | Electrical and I&C | Solid-State Devices
(e.g., transistors, circuit boards, computers) |
No |
| 102 | Electrical and I&C | Switches
(e.g., differential pressure indicating switches, differential pressure switches, pressure indicator switches, pressure switches, flow switches, conductivity switches, level indicating switches, temperature indicating switches, temperature switches, moisture switches, position switches, vibration switches, level switches, control switches, automatic transfer switches, manual transfer switches, manual disconnect switches, current switches, limit switches, knife switches) |
No |
| 103 | Electrical and I&C | Switchgear, Load Centers, Motor Control Centers, Distribution Panel Internal
Component Assemblies (may include internal devices such as, but not limited
to, switches, breakers, indicating lights, etc.)
(e.g., 4.16 kV switchgear, 480V load centers, 480V motor control centers, 250 VDC motor control centers, 6.9 kV switchgear units, 240/125V power distribution panels) |
No |
| 104 | Electrical and I&C | Transformers
(e.g., instrument transformers, load center transformers, small distribution transformers, large power transformers, isolation transformers, coupling capacitor voltage transformers) |
No
|
| 105 | Electrical and I&C | Transmitters
(e.g., differential pressure transmitters, pressure transmitters, flow transmitters, level transmitters, radiation transmitters, static pressure transmitters) |
No |
| 106 | Valves | Hydraulic Operated Valves | Yes (Bodies) |
| 107 | Valves | Explosive Valves | Yes (Bodies) |
| 108 | Valves | Manual Valves | Yes (Bodies) |
| 109 | Valves | Small Valves | Yes (Bodies) |
| 110 | Valves | Motor-Operated Valves | Yes (Bodies) |
| 111 | Valves | Air-Operated Valves | Yes (Bodies) |
| 112 | Valves | Main Steam Isolation Valves | Yes (Bodies) |
| 113 | Valves | Small Relief Valves | Yes (Bodies) |
| 114 | Valves | Check Valves | Yes (Bodies) |
| 115 | Valves | Safety Relief Valves | Yes (Bodies) |
| 116 | Valves | Dampers | No |
| 117 | Tanks | Air Accumulators | Yes |
| 118 | Tanks | Discharge Accumulators (Dampers) | Yes |
| 119 | Tanks | Boron Acid Storage Tanks | Yes |
| 120 | Tanks | Above Ground Oil Tanks | Yes |
| 121 | Tanks | Underground Oil Tanks | Yes |
| 122 | Tanks | Demineralized Water Tanks | Yes |
| 123 | Tanks | Neutron Shield Tank | Yes |
| 124 | Fans | Ventilation Fans | No |
| 125 | Fans | Other Fans | No |
| 126 | Miscellaneous | Emergency Lighting | No |
| 127 | Miscellaneous | Hose Stations | Yes |
2.2 Plant-Level Scoping Results
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Review Responsibilities
Primary - Branches responsible for systems
Secondary - Branch responsible for electrical engineering
2.2.1 Areas of Review
This section addresses the plant-level scoping results for license renewal. 10 CFR 54.21(a)(1) requires the applicant to identify and list structures and components subject to an aging management review (AMR). These are "passive," "long-lived" structures and components that are within the scope of license renewal. In addition, 10 CFR 54.21(a)(2) requires the applicant to describe and justify the methods used to identify these structures and components. The staff reviews the applicant's methodology separately following the guidance in Section 2.1.
The applicant should provide a list of all the plant systems and structures, identifying those that are within the scope of license renewal. If the list exists elsewhere, such as in the UFSAR, it is acceptable to merely identify the reference. The license renewal rule does not require the identification of all plant systems and structures. However, providing such a list may make the review more efficient. On the basis of the DBEs considered in the plant's CLB, and other CLB information relating to nonsafety-related systems and structures and certain regulated events, the applicant would identify those plant-level systems and structures within the scope of license renewal, as defined in 10 CFR 54.4(a). This is "scoping" of the plant-level systems and structures for license renewal. To verify that the applicant has properly implemented its methodology, the staff focuses its review on the implementation results to confirm that there is no omission of plant-level systems and structures within the scope of license renewal.
Examples of plant systems are the reactor coolant, containment spray, standby gas treatment (BWR), emergency core cooling, open and closed cycle cooling water, compressed air, chemical and volume control (PWR), standby liquid control (BWR), main steam, feedwater, condensate, steam generator blowdown (PWR), and auxiliary feedwater systems (PWR).
Examples of plant structures are the primary containment, secondary containment (BWR), control room, auxiliary building, fuel storage building, radwaste building, and ultimate heat sink cooling tower.
Examples of components are the reactor vessel, reactor vessel internals, steam generator (PWR), and light and heavy load-handling cranes. Some applicants may have categorized such components as plant "systems" for their convenience.
After the plant-level scoping, the applicant should identify the portions of the system or structure that perform an intended function, as defined in 10 CFR 54.4(b). Then the applicant should identify those structures and components that are "passive" and "long-lived" in accordance with 10 CFR 54.21(a)(1)(i) and (ii). These "passive," "long-lived" structures and components are those that are subject to an AMR. The staff reviews these results separately following the guidance in Sections 2.3 through 2.5.
The applicant has the flexibility to determine the set of systems and structures it considers as within the scope of license renewal, provided that this set includes the systems and structures that the NRC has determined are within the scope of license renewal. Therefore, the reviewer need not review all systems and structures that the applicant has identified to be within the scope of license renewal because the applicant has the option to include more systems and components than those defined to be within the scope of license renewal by 10 CFR 54.4.
The following areas relating to the methodology implementation results for the plant-level systems and structures are reviewed.
2.2.1.1 Systems and Structures Within the Scope of License Renewal
The reviewer verifies the applicant's identification of plant-level systems and structures that are within the scope of license renewal.
2.2.2 Acceptance Criteria
The acceptance criteria for the area of review define methods for determining whether the applicant has identified the systems and structures within the scope of license renewal in accordance with NRC regulations in 10 CFR 54.4. For the applicant's implementation of its methodology to be acceptable, the staff should have reasonable assurance that there has been no omission of plant-level systems and structures within the scope of license renewal.
2.2.2.1 Systems and Structures Within the Scope of License Renewal
Systems and structures are within the scope of license renewal as delineated
in 10 CFR 54.4(a) if they are
- Safety-related systems and structures that are relied upon to remain functional during and following DBEs [as defined in 10 CFR 50.49(b)(1)] to ensure the following functions:
- The integrity of the reactor coolant pressure boundary,
- The capability to shut down the reactor and maintain it in a safe shutdown condition, or
- The capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposure comparable to the guidelines in 10 CFR 50.34(a)(1), 50.67(b)(2), or 100.11, as applicable.
- Nonsafety-related systems and structures whose failure could prevent satisfactory
accomplishment of any of the functions identified in 10 CFR 54.4(a)(1)
above.
- Systems and structures relied on in safety analyses or plant evaluations to perform a function that demonstrates compliance with NRC regulations for fire protection (10 CFR 50.48), environmental qualification (10 CFR 50.49), PTS (10 CFR 50.61), ATWS (10 CFR 50.62), and SBO (10 CFR 50.63).
2.2.3 Review Procedures
The reviewer verifies the applicant's scoping results. If the reviewer requests additional information from the applicant regarding why a certain system or structure was not identified by the applicant as being within the scope of license renewal for the applicant's plant, the reviewer should provide a focused question, clearly explaining what information is needed, explaining why it is needed, and how it will allow the staff to make its safety finding. In addition, other staff members review the applicant's scoping and screening methodology separately following the guidance in Section 2.1. The reviewer should keep these other staff members informed of findings that may affect their review of the applicant's methodology. The reviewer should coordinate this sharing of information through the license renewal project manager.
For the area of review, the following review procedures are to be followed.
2.2.3.1 Systems and Structures Within the Scope of License Renewal
The reviewer determines whether the applicant has properly identified the plant-level systems and structures within the scope of license renewal by reviewing selected systems and structures that the applicant did not identify as being within the scope of license renewal to verify that they do not have any intended functions.
The reviewer should use the plant UFSAR, orders, applicable regulations, exemptions, and license conditions to determine the design basis for the SSCs (if components are identified as "systems" by the applicant). The design basis determines the intended function(s) of an SSC. Such functions determine whether the SSC is within the scope of license renewal under 54.4.
This section addresses scoping at a system or structure level. Thus, if any portion of a system or structure performs an intended function as defined in 10 CFR 54.4(b), the system or structure is within the scope of license renewal. The review of the individual portions of systems and structures that are within the scope of license renewal are addressed separately in Sections 2.3 through 2.5.
The applicant should submit a list of all plant-level systems and structures,
identifying those that are within the scope of license renewal. The reviewer
should sample selected systems and structures that the applicant did not identify
as within the scope of license renewal to determine if they perform any intended
functions. The following are examples:
- The applicant does not identify the radiation monitoring system as being
within the scope of license renewal. The reviewer may review the UFSAR to verify
that this particular system does not perform any intended functions at the applicant's
plant.
- The applicant does not identify the polar crane as being within the scope
of license renewal. The reviewer may review the UFSAR to verify that this particular
structure is not "Seismic II over I," denoting a non-seismic Category I structure
interacting with a Seismic Category I structure as described in Position C.2
of Regulatory Guide 1.29, "Seismic Design Classification" (Ref. 1).
- The applicant does not identify the fire protection pump house as within
the scope of license renewal. The reviewer may review the plant's commitments
to the fire protection regulation (10 CFR 50.48) to verify that this particular
structure does not perform any intended functions at the plant.
- The applicant uses the "spaces" approach for scoping electrical equipment and elects to include all electrical equipment on site to be within the scope of license renewal except for the 525 kV switchyard and the 230 kV transmission lines. The reviewer may review the UFSAR and commitments to the SBO regulation (10 CFR 50.63) to verify that the 525 kV switchyard and the 230 kV transmission lines do not perform any intended functions at the applicant's plant.
Table 2.2-1 contains additional examples based on lessons learned from the review of the initial license renewal applications, including a discussion of the plant-specific determination of whether a system or structure is within the scope of license renewal.
The applicant may choose to group similar components and structures together in commodity groups for separate analyses. If only a portion of a system or structure has an intended function and is addressed separately in a specific commodity group, it is acceptable for an applicant to identify that system or structure as not being within the scope of license renewal. However, for completeness, the applicant should include some reference indicating that the portion of the system or structure with an intended function that is evaluated with the commodity group.
Section 2.1 contains additional guidance on the following:
- Commodity groups
- Complex assemblies
- Hypothetical failure
- Cascading
If the reviewer does not identify any omissions of systems and structures from
those within the scope of license renewal, the staff would have reasonable assurance
that the applicant has identified the systems and structures within the scope
of license renewal.
- If the reviewer determines that the applicant has satisfied the criteria described in this review section, the staff would have reasonable assurance that the applicant has identified the systems and structures within the scope of license renewal.
2.2.4 Evaluation Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provision of the SRP-LR and that the staff's evaluation supports conclusions of the following type, to be included in the safety evaluation report:
The staff concludes that there is reasonable assurance that the applicant has appropriately identified the systems and structures within the scope of license renewal in accordance with 10 CFR 54.4.
2.2.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specific portions of NRC regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
2.2.6 References
1. Regulatory Guide 1.29, Rev. 2, "Seismic Design Classifications," September 1978.
Table 2.2-1. Examples of System and Structure Scoping and Basis for Disposition
| Example | Disposition |
|---|---|
| Recirculation cooling water system | One function of the recirculation cooling water system is to remove decay heat from the stored fuel in the spent fuel pool. However, the fuel handling accident for the plant assumes that the spent fuel pool cooling systems, and thus the recirculation cooling water system, is not functional during or following such an event. Thus, the recirculation cooling water system is not within the scope of license renewal based on this function. |
| SBO diesel generator building | The plant's UFSAR indicates that certain structural components of the SBO diesel generator building for the plant are designed to preclude seismic failure and subsequent impact of the structure on the adjacent safety-related emergency diesel generator building. In addition, the UFSAR indicates that certain equipment attached to the roof of the building has been anchored to resist tornado wind loads. Thus, the SBO diesel generator building is within the scope of license renewal. |
2.3 Scoping and Screening Results: Mechanical Systems
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Review Responsibilities
Primary - Branches responsible for systems
Secondary - None
2.3.1 Areas of Review
This section addresses the mechanical systems scoping and screening results
for license renewal. Typical mechanical systems consist of the following:
- Reactor coolant system (such as reactor vessel and internals, components
forming part of coolant pressure boundary, coolant piping system and connected
lines, and steam generators).
- Engineered safety features (such as containment spray and isolation systems,
standby gas treatment system, emergency core cooling system, and fan cooler
system).
- Auxiliary systems (such as new and spent fuel storage, spent fuel cooling
and cleanup systems, suppression pool cleanup system, load handling system,
open and closed cycle cooling water systems, ultimate heat sink, compressed
air system, chemical and volume control system, standby liquid control system,
coolant storage/refueling water systems, ventilation systems, diesel generator
system, and fire protection system).
- Steam and power conversion system (such as turbines, main and extraction steam, feedwater, condensate, steam generator blowdown, and auxiliary feedwater).
10 CFR 54.21(a)(1) requires an applicant to identify and list structures and components subject to an aging management review (AMR). These are "passive," "long-lived" structures and components that are within the scope of license renewal. In addition, 10 CFR 54.21(a)(2) requires an applicant to describe and justify the methods used to identify these structures and components. The staff reviews the applicant's methodology separately following the guidance in Section 2.1. To verify that the applicant has properly implemented its methodology, the staff focuses its review on the implementation results. Such a focus allows the staff to confirm that there is no omission of mechanical system components that are subject to an AMR by the applicant. If the review identifies no omission, the staff has the basis to find that there is reasonable assurance that the applicant has identified the mechanical system components that are subject to an AMR.
An applicant should list all plant-level systems and structures. On the basis of the DBEs considered in the plant's CLB and other CLB information relating to nonsafety-related systems and structures and certain regulated events, the applicant should identify those plant-level systems and structures within the scope of license renewal, as defined in 10 CFR 54.4(a). This is "scoping" of the plant-level systems and structures for license renewal. The staff reviews the applicant's plant-level "scoping" results separately following the guidance in Section 2.2.
For a mechanical system that is within the scope of license renewal, the applicant should identify the portions of the system that perform an intended function, as defined in 10 CFR 54.4(b). The applicant may identify these particular portions of the system in marked-up piping and instrument diagrams (P&IDs) or other media. This is "scoping" of mechanical components in a system to identify those that are within the scope of license renewal for a system.
For these identified mechanical components, the applicant must identify those that are "passive" and "long-lived" as required by 10 CFR 54.21(a)(1)(i) and (ii). These "passive," "long-lived" mechanical components are those that are subject to an AMR. This is "screening" of mechanical components in a system to identify those that are "passive" and "long-lived."
The applicant has the flexibility to determine the set of structures and components for which an AMR is performed, provided that this set includes the structures and components for which the NRC has determined that an AMR is required. This is based on the SOC for the license renewal rule (60 FR 22478). Therefore, the reviewer need not review all components that the applicant has identified as subject to an AMR because the applicant has the option to include more components than those required to be subject to an AMR pursuant to 10 CFR 54.21(a)(1).
2.3.2 Acceptance Criteria
The acceptance criteria for the areas of review define methods for determining whether the applicant has met the requirements of NRC regulations in 10 CFR 54.21(a)(1). For the applicant's implementation of its methodology to be acceptable, the staff should have reasonable assurance that there has been no omission of mechanical system components that are subject to an AMR.
2.3.2.1 Components Within the Scope of License Renewal
Mechanical components are within the scope of license renewal as delineated
in 10 CFR 54.4(a) if they are
- Safety-related SSCs that are relied upon to remain functional during and following DBEs [as defined in 10 CFR 50.49(b)(1)] to ensure the following functions:
- The integrity of the reactor coolant pressure boundary;
- The capability to shut down the reactor and maintain it in a safe shutdown condition; or
- The capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposure comparable to the guidelines in
10 CFR 50.34(a)(1), 10 CFR 50.67(b)(2), or 10 CFR 100.11, as applicable.
- All nonsafety-related SSCs whose failure could prevent satisfactory accomplishment
of any of the functions identified in 10 CFR 54.4(a)(1)(i), (ii), or (iii).
- All SSCs relied on in safety analyses or plant evaluations to perform a function that demonstrates compliance with NRC regulations for fire protection (10 CFR 50.48), environmental qualification (10 CFR 50.49), PTS (10 CFR 50.61), ATWS (10 CFR 50.62), and SBO (10 CFR 50.63).
2.3.2.2 Components Subject to an Aging Management Review
Mechanical components are subject to an AMR if they are within the scope of license renewal and perform an intended function as defined in 10 CFR 54.4(b) without moving parts or a change in configuration or properties ("passive"), and are not subject to replacement based on a qualified life or specified time period ("long-lived") [10 CFR 54.21(a)(1)(i) and (ii)].
2.3.3 Review Procedures
The reviewer verifies the applicant's scoping and screening results. If the reviewer requests additional information from the applicant regarding why a certain component was not identified by the applicant as being within the scope of license renewal or subject to an AMR for the applicant's plant, the reviewer should provide a focused question, that clearly explains what information is needed, why the information is needed, and how the information will allow the staff to make its safety finding. In addition, other staff members review the applicant's scoping and screening methodology separately following the guidance in Section 2.1. The reviewer should keep these other staff members informed of findings that may affect their review of the applicant's methodology. The reviewer should coordinate this sharing of information through the license renewal project manager.
For each area of review, the following review procedures are to be followed.
2.3.3.1 Components Within the Scope of License Renewal
In this step, the staff determines whether the applicant has properly identified the components that are within the scope of license renewal. The Rule requires applicants, to identify components that are subject to an AMR; not components that are within the scope of license renewal (WSLR). Whereas in the past LRAs have included a table of components that are WSLR, the staff does not expect that information to be submitted with future LRAs. Although that information will be available at plant sites for inspection, the reviewer must determine through sampling of P&IDs, and review of FSAR and other plant documents, what portion of the components are within scope. The reviewer must check to see if any components exist that the staff believes are within scope but are not identified by the applicant as being subject to an AMR (and request that the applicant provide justification for omitting those components that are "passive" and "long lived").
The reviewer should use the UFSAR, orders, applicable regulations, exemptions, and license conditions to determine the design basis for the SSCs. The design basis specifies the intended function(s) of the system(s). That intended function is used to determine the components within that system that are required for the system to perform its intended functions.
The reviewer should focus the review on those components that are not identified as being within the scope of license renewal, especially the license renewal boundary points and major flow paths. The reviewer should verify that the components do not have intended functions. Portions of the system identified as being within the scope of license renewal by the applicant do not have to be reviewed because the applicant has the option to include more components within the scope than the rule requires.
Further, the reviewer should select system functions described in the UFSAR that are required by 10 CFR 54.4 to verify that components having intended functions were not omitted from the scope of the rule.
For example, if a reviewer verifies that a portion of a system does not perform an intended function, is not identified as being subject to an AMR by the applicant, and is isolated from the portion of the system that is identified as being subject to an AMR by a boundary valve, the reviewer should verify that the boundary valve is subject to an AMR, or that the valve is not necessary for the within-scope portion of the system to perform its intended function. Likewise, the reviewer should identify, to the extend practical, the system functions of the piping runs and components that are identified as not being within the scope of license renewal to ensure they do not have intended functions that meet the requirements of 10 CFR 54.4.
Section 2.1 contains additional guidance on the following:
- Commodity groups
- Complex assemblies
- Hypothetical failure
- Cascading
If the reviewer does not identify any omissions of components within the scope of license renewal, the reviewer would have reasonable assurance that the applicant has identified the components within the scope of license renewal for the mechanical systems.
Table 2.3-1 provides examples of mechanical components scoping lessons learned from the review of the initial license renewal applications and the basis for their disposition.
2.3.3.2 Components Subject to an Aging Management Review
In this step, the reviewer determines whether the applicant has properly identified the components subject to an AMR from among those which are within the scope of license renewal (i.e., those identified in Subsection 2.3.3.1). The reviewer should review selected components that the applicant has identified as within the scope of license renewal but as not subject to an AMR. The reviewer should verify that the applicant has not omitted from an AMR components that perform intended functions without moving parts or without a change in configuration or properties and that are not subject to replacement on the basis of a qualified life or specified time period.
Starting with the boundary verified in Subsection 2.3.3.1, the reviewer should sample components that are within the scope of license renewal for that system, but were not identified by the applicant as subject to an AMR. Only components that are "passive" and "long-lived" are subject to an AMR. Table 2.1-5 is provided for the reviewer to assist in identifying whether certain components are "passive." The applicant should justify omitting a component from an AMR that is within the scope of license renewal at their facility and is listed as "passive" on Table 2.1-5. Although Table 2.1-5 is extensive, it may not be all inclusive. Thus, the reviewer should use other available information sources, such as prior application reviews, to determine whether a component may be subject to an AMR.
For example, an applicant has marked a boundary of a certain system that is within the scope of license renewal. The marked-up diagram shows that there are pipes, valves, and air compressors within this boundary. The applicant has identified piping and valve bodies as subject to an AMR. Because Table 2.1-5 indicates that air compressors are not subject to an AMR, the reviewer should find the applicant's determination acceptable.
Section 2.1 contains additional guidance on screening the following:
- Consumables
- Heat exchanger intended functions
- Multiple functions
If the reviewer does not identify any omissions of components from those that are subject to an AMR, the staff would then have reasonable assurance that the applicant has identified the components subject to an AMR for the mechanical systems.
Table 2.3-2 provides examples of mechanical components screening developed from lessons learned during the review of the initial license renewal applications and bases for their disposition.
If the applicant determines that a component is subject to an AMR, the applicant should also identify the component's intended function, as defined in 10 CFR 54.4. Such functions must be maintained by any necessary AMRs. Table 2.3-3 provides examples of mechanical component intended functions.
2.3.4 Evaluation Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provisions of the SRP-LR and that the staff's evaluation supports conclusions of the following type, to be included in the safety evaluation report:
The staff concludes that there is reasonable assurance that the applicant has appropriately identified the mechanical system components subject to an aging management review in accordance with the requirements stated in 10 CFR 54.21(a)(1).
2.3.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specific portions of NRC regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
2.3.6 References
None.
Table 2.3-1. Examples of Mechanical Components Scoping and Basis for Disposition
| Example | Disposition |
|---|---|
| Piping segment that provides structural support | The safety-related/nonsafety-related boundary along a pipe run may occur at a valve location. The nonsafety-related piping segment between this valve and the next seismic anchor provides structural support in a seismic event. This piping segment is within the scope of license renewal. |
| Containment heating and ventilation system ductwork downstream of the fusible links providing cooling to the steam generator compartment and reactor vessel annulus | This nonsafety-related ductwork provides cooling to support the applicant's environmental qualification program. However, the failure of the cavity cooling system ductwork will not prevent the satisfactory completion of any critical safety function during and following a design basis event. Thus, this ductwork is not within the scope of license renewal. |
| Standpipe installed inside the fuel oil storage tank | The standpipe as described in the applicant's CLB ensures that there is sufficient fuel oil reserve for the emergency diesel generator to operate for the number of days specified in the plant technical specifications following DBEs. Therefore, this standpipe is within the scope of license renewal. |
| Insulation on boron injection tank | The temperature is high enough that insulation is not necessary to prevent boron precipitation. The plant technical specifications require periodic verification of the tank temperature. Thus, the insulation is not relied on to ensure the function of the emergency system and is not within the scope of license renewal. |
| Pressurizer spray head | The spray head is not credited for the mitigation of any accidents addressed in the UFSAR accident analyses. The function of the pressurizer spray is to reduce reactor coolant system pressure during normal operating conditions. Therefore, the spray head is not within the scope of license renewal. |
Table 2.3-2. Examples of Mechanical Components Screening and Basis for Disposition
| Example | Disposition |
|---|---|
| Diesel engine jacket water heat exchanger, and portions of the diesel fuel oil system and starting air system supplied by a vendor on a diesel generator skid | These are "passive," "long-lived" components having intended functions. They are subject to an AMR for license renewal even though the diesel generator is considered "active." |
| Fuel assemblies | The fuel assemblies are replaced at regular intervals based on the fuel cycle of the plant. They are not subject to an AMR. |
| Valve internals (such as disk and seat) | 10 CFR 54.21(a)(1)(i) excludes valves, other than the valve body, from AMR. The statements of consideration of the license renewal rule provide the basis for excluding structures and components that perform their intended functions with moving parts or with a change in configuration or properties. Although the valve body is subject to an AMR, valve internals are not. |
Table 2.3-3. Examples of Mechanical Component Intended Functions
| Component | Intended Functiona |
|---|---|
| Piping | Pressure boundary |
| Valve body | Pressure boundary |
| Pump casing | Pressure boundary |
| Orifice | Pressure boundary flow restriction |
| Heat exchanger | Pressure boundary heat transfer |
| Reactor vessel internals | Structural support of fuel assemblies, control rods, and incore instrumentation, to maintain core configuration and flow distribution |
| a The component intended functions are those that support the system intended functions. For example, a heat exchanger in the spent fuel cooling system has a pressure boundary intended function, but may not have a heat transfer function. Similarly, not all orifices have flow restriction as an intended function. | |
2.4 Scoping and Screening Results: Structures
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Review Responsibilities
Primary - Branch responsible for plant systems
Secondary - None
2.4.1 Areas of Review
This section addresses the scoping and screening results of structures and
structural components for license renewal. Typical structures include the following:
- The primary containment structure;
- Building structures (such as the intake structure, diesel generator building,
auxiliary building, and turbine building);
- Component supports (such as cable trays, pipe hangers, elastomer vibration
isolators, equipment frames and stanchions, and HVAC ducting supports);
- Nonsafety-related structures whose failure could prevent safety-related SSC from performing their intended functions (that is, seismic Category II over I structures).
Typical structural components include the following: liner plates, walls, floors, roofs, foundations, doors, beams, columns, and frames.
10 CFR 54.21(a)(1) requires the applicant to identify and list structures and components subject to an aging management review (AMR). These are "passive," "long-lived" structures and components that are within the scope of license renewal. In addition, 10 CFR 54.21(a)(2) requires an applicant to describe and justify the methods used to identify these structures and components. The staff reviews the applicant's methodology separately following the guidance in Section 2.1. To verify that the applicant has properly implemented its methodology, the staff focuses its review on the implementation results. Such a focus allows the staff to confirm that there is no omission of structures that are subject to an AMR by the applicant. If the staff's review identifies no omission, the staff has a basis to find that there is reasonable assurance that the applicant has identified the structural components that are subject to an AMR.
An applicant should list all plant-level systems and structures. On the basis of the DBEs considered in the plant's CLB and other CLB information relating to nonsafety-related systems and structures and certain regulated events, the applicant should identify those plant-level systems and structures within the scope of license renewal, as defined in 10 CFR 54.4(a). This is "scoping" of the plant-level systems and structures for license renewal. The staff reviews the applicant's plant-level "scoping" results separately following the guidance in Section 2.2.
For structures that are within the scope of license renewal, an applicant must identify the structural components that are "passive" and "long-lived" in accordance with 10 CFR 54.21(a)(1)(i) and (ii). These "passive," "long-lived" structural components are those that are subject to an AMR ("screening"). The applicant's methodology implementation results for identifying structural components subject to an AMR is the area of review.
The applicant has the flexibility to determine the set of structures and components for which an AMR is performed, provided that this set includes the structures and components for which the NRC has determined that an AMR is required. This flexibility is described in the statements of consideration for the License Renewal Rule (60 FR 22478). Therefore, the reviewer should not focus the review on structural components that the applicant has already identified as subject to an AMR because it is an applicant's option to include more structural components than those subject to an AMR, pursuant to 10 CFR 54.21(a)(1). Rather, the reviewer should focus on those structural components that are not included by the applicant as subject to an AMR to ensure that they do not perform an intended function as defined in 10 CFR 54.4(b) or are not "passive" and "long-lived."
2.4.2 Acceptance Criteria
The acceptance criteria for the areas of review define methods for determining whether the applicant has met the requirements of NRC regulations in 10 CFR 54.21(a)(1). For the applicant's implementation of its methodology to be acceptable, the staff should have reasonable assurance that there has been no omission of structural components that are subject to an AMR.
2.4.2.1 Structural Components Subject to an Aging Management Review
Structural components are within the scope of license renewal as delineated
in 10 CFR 54.4(a) if they are
- Safety-related SSCs that are relied upon to remain functional during and following DBEs [as defined in 10 CFR 50.49(b)(1)] to ensure the following functions:
- The integrity of the reactor coolant pressure boundary;
- The capability to shut down the reactor and maintain it in a safe shutdown condition; or
- The capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposure comparable to the guidelines in 10 CFR 50.34(a)(1), 10 CFR 50.67(b)(2), or 10 CFR 100.11, as applicable.
- All nonsafety-related SSCs whose failure could prevent satisfactory accomplishment
of any of the functions identified in 10 CFR 54.4(a)(1)(i), (ii), or (iii).
- All SSCs relied on in safety analyses or plant evaluations to perform a function that demonstrates compliance with NRC regulations for fire protection (10 CFR 50.48), environmental qualification (10 CFR 50.49), PTS (10 CFR 50.61), ATWS (10 CFR 50.62), and SBO (10 CFR 50.63).
Structural components are subject to an AMR if they are within the scope of license renewal and perform an intended function as defined in 10 CFR 54.4(b) without moving parts or a change in configuration or properties ("passive"), and are not subject to replacement based on a qualified life or specified time period ("long-lived") [10 CFR 54.21(a)(1)(i) and (ii)].
2.4.3 Review Procedures
The reviewer verifies the applicant's scoping/screening results. If the reviewer request additional information from the applicant regarding why a certain structure was not identified by the applicant as subject to an AMR for the plant, the reviewer should provide a focused question that clearly explain what information is needed, why the information is needed, and how the information will allow the staff to make its safety finding. In addition, other staff members review the applicant's scoping and screening methodology separately following the guidance in Section 2.1. The reviewer should keep these other staff members informed of findings that may affect their review of the applicant's methodology. The reviewer should coordinate this sharing of information through the license renewal project manager.
For each area of review, the following review procedures are to be followed:
2.4.3.1 Structural Components Within the Scope of License Renewal
In this step, the staff determines which structures and structural components are within the scope of license renewal. The Rule requires applicants, to identify structures that are subject to an AMR; not structures that are within the scope of license renewal (WSLR). Whereas in the past LRAs have included a table of structures that are WSLR, the staff does not expects that information to be submitted with future LRAs. Although that information will be available at plant sites for inspection, the reviewer must determine through sampling of P&IDs, and review of the FSAR and other plant documents, what portion of the components are within scope. The reviewer should check to see if any structures exist that the staff believes are within scope but are not identified by the applicant as being subject to an AMR (and request that the applicant provide justification for omitting those structures that are "passive" and "long lived").
2.4.3.2 Structural Components Subject to an Aging Management Review
In general, structural components are "passive" and "long lived." Thus, they are subject to an AMR if they are within the scope of license renewal. For each of the plant-level structures within the scope of license renewal, an applicant should identify those structural components that have intended functions. For example, the applicant may identify that its auxiliary building is within the scope of license renewal. For this auxiliary building, the applicant may identify the structural components of beams, concrete walls, blowout panels, etc., that are subject to an AMR. The applicant should justify omitting a component from an AMR that is within the scope of license renewal at their facility and is listed as "passive" on Table 2.1-5. Although Table 2.1-5 is extensive, it may not be all inclusive. Thus, the reviewer should use other available information, such as prior application reviews, to determine whether a component may be subject to an AMR.
As set forth below, the reviewer should focus on individual structure not subject to an AMR, one at a time, to confirm that the structural components that have intended functions have been identified by the applicant. In a few instances, only portions of a particular building are within the scope of license renewal. For example, a portion of a particular turbine building provides shelter for some safety-related equipment, which is an intended function, and the remainder of this particular building does not have any intended functions. In this case, the reviewer should verify that the applicant has identified the relevant particular portion of the turbine building as being within the scope of license renewal and subject to an AMR.
The reviewer should use the UFSAR, orders, applicable regulations, exemptions, and license conditions to determine the design basis for the SSCs. The design basis specifies the intended function(s) of the system(s). That intended function is used to determine the components within that system that are required for the system to perform its intended functions.
The reviewer should focus the review on those structural components that have not been identified as being within the scope of license renewal. For example, for a building within the scope of license renewal, if an applicant did not identify the building roof as subject to an AMR, the reviewer should verify that the roof has no intended functions, such as a "Seismic II over I" concern in accordance with the plant's CLB. The reviewer need not verify all structural components that have been identified as subject to an AMR by the applicant because the applicant has the option to include more structural components than the rule requires to be subject to an AMR.
Further, the reviewer should select functions described in the UFSAR to verify that structural components having intended functions were not omitted from the scope of the review. For example, if the UFSAR indicates that a dike within the fire pump house prevents a fuel oil fire from spreading to the electrically driven fire pump, the reviewer should verify that this dike has been identified as being within the scope of license renewal. Another example, if a non-safety-related structure or component is included in the plant's CLB as a part of the safe shutdown path resulting from the resolution of USI A-46, the reviewer should verify that the structure or component has been included within the scope of license renewal.
The applicant should also identify the intended functions of structural components. Table 2.1-4 provides typical "passive" structural component intended functions.
The staff has developed additional scoping/screening guidance. For example,
some structural components may be grouped together as a commodity, such as pipe
hangers, and some structural components are considered consumable materials,
such as sealants. Additional guidance on these and others are contained in Section
2.1 for the following:
- Commodity groups
- Hypothetical failure
- Cascading
- Consumables
- Multiple functions
If the reviewer does not identify any omissions of components from those that are subject to an AMR, the staff would have reasonable assurance that the applicant has identified the components subject to an AMR for the structural systems.
Table 2.4-1 provides examples of structural components scoping/screening lessons learned from the review of initial license renewal applications and the basis for disposition.
If the applicant determines that a structural component may be subject to an AMR, the applicant should also identify the component's intended functions, as defined in 10 CFR 54.4. Such functions must be maintained by any necessary AMPs.
If the reviewer determines that the applicant has satisfied the criteria described in this review section, the staff would have reasonable assurance that the applicant has identified the components that are within the scope of license renewal and subject to an AMR.
2.4.4 Evaluation Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provisions of the SRP-LR and that the staff's evaluation supports conclusions of the following type, to be included in the safety evaluation report:
The staff concludes that there is reasonable assurance that the applicant has appropriately identified the structural components subject to an aging management review in accordance with the requirements stated in 10 CFR 54.21(a)(1).
2.4.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specific portions of NRC regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
2.4.6 References
None.
Table 2.4-1. Examples of Structural Components Scoping/Screening and Basis for Disposition
| Example | Disposition |
|---|---|
| Roof of turbine building | An applicant indicates that degradation or loss of its turbine building roof will not result in the loss of any intended functions. The turbine building contains safety-related SSCs in the basement, which would remain sheltered and protected by several reinforced concrete floors if the turbine building roof were to degrade. Because this roof does not perform an intended function, it is not within the scope of license renewal. |
| Post-tensioned containment tendon gallery | The intended function of the post-tensioning system is to impose compressive forces on the concrete containment structure to resist the internal pressure resulting from a DBA with no loss of structural integrity. Although the tendon gallery is not relied on to maintain containment integrity during DBEs, operating experience indicates that water infiltration and high humidity in the tendon gallery can contribute to a significant aging effect on the vertical tendon anchorages that could potentially result in loss of the ability of the post-tensioning system to perform its intended function. However, containment inspections provide reasonable assurance that the aging effects of the tendon anchorages, including those in the gallery, will continue to perform their intended functions. Because the tendon gallery itself does not perform an intended function, it is not within the scope of license renewal. |
| Water-stops | Ground water leakage into the auxiliary building could occur as a result of degradation to the water-stops. This leakage may cause flooding of equipment within the scope of license renewal. (The plant's UFSAR discusses the effects of flooding.) The water-stops perform their functions without moving parts or a change in configuration, and they are not typically replaced. Thus, the water-stops are subject to an AMR. However, they need not be called out explicitly in the scoping/screening results if they are included as parts of structural components that are subject to an AMR. |
2.5 Scoping and Screening Results: Electrical
And Instrumentation
And Controls Systems
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Review Responsibilities
Primary - Branch responsible for electrical and instrumentation and controls engineering
Secondary - None
2.5.1 Areas of Review
This review plan section addresses the electrical and instrumentation and controls (I&C) scoping and screening results for license renewal. Typical electrical and I&C components that are subject to an aging management review (AMR) for license renewal include electrical cables and connections.
10 CFR 54.21(a)(1) requires an applicant to identify and list structures and components subject to an AMR. These are "passive," "long-lived" structures and components that are within the scope of license renewal. In addition, 10 CFR 54.21(a)(2) requires an applicant to describe and justify the methods used to identify these structures and components. The staff reviews the applicant's methodology separately following the guidance in Section 2.1. To verify that the applicant has properly implemented its methodology, the staff focuses its review on the implementation results. Such focus gives the staff reasonable assurance that there has been no omission of electrical and I&C components that are subject to an AMR by the applicant. If the staff's review identifies no omission, the staff has a basis to find that there is reasonable assurance that the applicant has identified the electrical and I&C components subject to an AMR.
An applicant should list all plant-level systems and structures. On the basis of the DBEs considered in the plant's CLB and other CLB information relating to nonsafety-related systems and structures and certain regulated events, the applicant would identify those plant-level systems and structures that are within the scope of license renewal, as defined in 10 CFR 54.4(a). This is "scoping" of the plant-level systems and structures for license renewal. The staff reviews the applicant's plant-level "scoping" results separately following the guidance in Section 2.2.
For an electrical and I&C system that is within the scope of license renewal, an applicant may not identify the specific electrical and I&C components that are subject to an AMR. For example, an applicant may not "tag" each specific length of cable that is "passive" and "long-lived," and performs an intended function as defined in 10 CFR 54.4(b). Instead, an applicant may use the so-called "plant spaces" approach (Ref. 1), which is explained below. The "plant spaces" approach provides efficiencies in AMR of electrical equipment located within the same plant space environment.
Under the "plant spaces" approach, an applicant would identify all "passive," "long-lived" electrical equipment within a specified plant space as subject to an AMR, regardless of whether these components perform any intended functions. For example, an applicant could identify all "passive," "long-lived" electrical equipment located within the turbine building ("plant space") to be subject to an AMR for license renewal. In the subsequent AMR, the applicant would evaluate the environment of the turbine building to determine the appropriate aging management activities for this equipment. The applicant has options to further refine this encompassing scope on an as-needed basis. For this example, if the applicant identified elevated temperatures in a particular area within the turbine building, the applicant may elect to further refine the scope in this particular area by identifying electrical equipment that is not subject to an AMR and excluding this equipment from the AMR. In this case, the excluded electrical equipment would be reported in the application as not being subject to an AMR.
10 CFR 54.21(a)(1)(i) provides many examples of electrical and I&C components that are not considered to be "passive" and are not subject to an AMR for license renewal. Therefore, the applicant is expected to identify only a few electrical and I&C components, such as electrical penetrations, cables, and connections, that are "passive" and subject to an AMR. However, the TLAA evaluation requirements in 10 CFR 54.21(c) apply to environmental qualification of electrical equipment, which is not limited to "passive" components.
An applicant has the flexibility to determine the set of electrical and I&C components for which an AMR is performed, provided that this set includes the electrical and I&C components for which the NRC has determined an AMR is required. This is based on the statements of consideration for the License Renewal Rule (60 FR 22478). Therefore, the reviewer need not review all components that the applicant has identified as subject to an AMR because the applicant has the option to include more components than those required by 10 CFR 54.21(a)(1).
2.5.2 Acceptance Criteria
The acceptance criteria for the areas of review define methods for determining whether the applicant has met the requirements of NRC regulations in 10 CFR 54.21(a)(1). For the applicant's implementation of its methodology to be acceptable, the staff should have reasonable assurance that there has been no omission of electrical and I&C system components that are subject to an AMR.
2.5.2.1 Components Within the Scope of License Renewal
Electrical and I&C components are within the scope of license renewal as
delineated in
10 CFR 54.4(a) if they are
- Safety-related SSCs that are relied upon to remain functional during and following DBEs (as defined in 10 CFR 50.49(b)(1)) to ensure the following functions:
- The integrity of the reactor coolant pressure boundary;
- The capability to shut down the reactor and maintain it in a safe shutdown condition; or
- The capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposure comparable to the guidelines in
10 CFR 50.34(a)(1), 10 CFR 50.67(b)(2) or 10 CFR 100.11, as applicable.
- All nonsafety-related SSCs whose failure could prevent satisfactory accomplishment
of any of the functions identified in
10 CFR 54.4(a)(1)(i), (ii) or (iii).
- All SSCs relied on in safety analyses or plant evaluations to perform a function that demonstrates compliance with NRC regulations for fire protection (10 CFR 50.48), environmental qualification (10 CFR 50.49), PTS (10 CFR 50.61), ATWS (10 CFR 50.62), and SBO (10 CFR 50.63).
2.5.2.2 Components Subject to an Aging Management Review
Electrical and I&C components are subject to an AMR if they are within the scope of license renewal and perform an intended function as defined in 10 CFR 54.4(b) without moving parts or without a change in configuration or properties ("passive"), and are not subject to replacement based on a qualified life or specified time period ("long-lived") [10 CFR 54.21(a)(1)(i) and (ii)].
2.5.3 Review Procedures
The reviewer verifies the applicant's scoping and screening results. If the reviewer requests additional information from the applicant regarding why a certain component was not identified by the applicant as being within the scope of license renewal or subject to an AMR for the plant, the reviewer should provide a focused question, that clearly explain what information is needed, why the information is needed, and how the information will allow the staff to make its safety finding. In addition, other staff members review the applicant's scoping and screening methodology separately following the guidance in Section 2.1. The reviewer should keep these other staff members informed of findings that may affect their review of the applicant's methodology. The reviewer should coordinate this sharing of information through the license renewal project manager.
The reviewer should verify that an applicant has identified in the license renewal application the electrical and I&C components that are subject to an AMR for its plant. The review procedures are presented below and assume that the applicant has performed "scoping" and "screening" of electrical and I&C system components in that sequence. However, the applicant may elect to perform "screening" before "scoping", which is acceptable because regardless of the sequence, the end result should encompass the electrical and I&C components that are subject to an AMR.
The scope of 10 CFR 50.49 electric equipment to be included within 10 CFR 54.4(a)(3) is that "long-lived" (qualified life of 40 years or greater) equipment already identified by licensees under 10 CFR 50.49(b), which specifies certain electric equipment important to safety. Licensees may rely upon their listing of environmental qualification equipment, as required by 10 CFR 50.49(d), for purposes of satisfying 10 CFR 54.4(a)(3) with respect to equipment within the scope of 10 CFR 50.49 (60 FR 22466). However, the License Renewal Rule has a requirement (10 CFR 54.21(c)) on the evaluation of TLAAs, including environmental qualification (10 CFR 50.49). Environmental qualification equipment is not limited to "passive" equipment. The applicant may identify environmental qualification equipment separately for TLAA evaluation and not include such equipment as subject to an AMR under 10 CFR 54.21(a)(1). The environmental qualification equipment identified for TLAA evaluation would include the "passive" environmental qualification equipment subject to an AMR. The TLAA evaluation would ensure that the environmental qualification equipment would be functional for the period of extended operation. The staff reviews the applicant's environmental qualification TLAA evaluation separately following the guidance in Section 4.4.
For each area of review, the following review procedures are to be followed.
2.5.3.1 Components Within the Scope of License Renewal
In this step, the staff determines whether the applicant has properly identified the components that are within the scope of license renewal. The Rule requires applicants to identify components that are subject to an AMR; not components that are within the scope of license renewal (WSLR). Whereas, in the past, LRAs have included a table of components that are WSLR, the staff does not expects that information to be submitted with future LRAs. Although that information will be available at plant sites for inspection, the reviewer must determine through sampling of one line diagrams, and review of FSAR and other plant documents, what portion of the components are within the scope of license renewal. The reviewer must check to see if any components exist that the staff believes are within the scope but are not identified by the applicant as being subject to AMR (any request that the applicant provide justification for omitting those components that are "passive" and "long lived").
The reviewer should use the UFSAR, orders, applicable regulations, exemptions, and license conditions to determine the design basis for the SSCs. The design basis specifies the intended function(s) of the system(s). That intended function is used to determine the components within that system that are required for the system to perform its intended functions.
The applicant may use the "plant spaces" approach in scoping electrical and I&C components for license renewal. In the "plant spaces" approach, an applicant may indicate that all electrical and I&C components located within a particular plant area ("plant space"), such as the containment and auxiliary building, are within the scope of license renewal. The applicant may also indicate that all electrical and I&C components located within another plant area ("plant space"), such as the warehouse, are not within the scope of license renewal. Table 2.5-1 contains examples of this "plant spaces" approach and the corresponding review procedures.
The applicant would use the "plant spaces" approach for the subsequent AMR of the electrical and I&C components. The applicant would evaluate the environment of the "plant spaces" to determine the appropriate aging management activities for equipment located there. The applicant has the option to further refine this encompassing scope on an as-needed basis. For example, if the applicant identified elevated temperatures in a particular area within a building ("plant space"), the applicant may elect to identify only those "passive," "long-lived" electrical and I&C components that perform an intended function in this particular area as subject to an AMR. This approach of limiting the "plant spaces" is consistent with the "plant spaces" approach. In this case, the reviewer verifies that the applicant has specifically identified the electrical and I&C components that may be within the scope of license renewal in these limited "plant spaces." The reviewer should verify that the electrical and I&C components that the applicant has elected to further exclude do not indeed have any intended functions as defined in 10 CFR 54.4(b).
Section 2.1 contains additional guidance on scoping the following:
- Commodity groups
- Complex assemblies
- Scoping events
- Hypothetical failure
- Cascading
If the reviewer does not identify any omissions of components from those that are within the scope of license renewal, the staff would have reasonable assurance that the applicant has identified the components within the scope of license renewal for the electrical and I&C systems.
2.5.3.2 Component Subject to an Aging Management Review
In this step, the reviewer determines whether the applicant has properly identified the components subject to an AMR from among those which are within the scope of license renewal (i.e., those identified in Subsection 2.5.3.1). The reviewer should review selected components that the applicant has identified as being within the scope of license renewal to verify that the applicant has identified these components as being subject to an AMR if they perform intended functions without moving parts or without a change in configuration or properties and are not subject to replacement on the basis of a qualified life or specified time period. The description of "passive" may also be interpreted to include structures and components that do not display "a change in state."
Only components that are "passive" and "long-lived" are subject to an AMR. Table 2.1-5 lists many typical components and structures, and their associated intended functions, and identifies whether they are "passive." The reviewer should use Table 2.1-5 in identifying whether certain components are "passive." The reviewer should verify that electrical and I&C components identified as "passive" in Table 2.1-5 have been included by the applicant as being subject to an AMR. Although Table 2.1-5 is extensive, it may not be all inclusive. Thus, the reviewer should use other available information sources, such as prior application reviews, to determine whether a component may be subject to an AMR.
Section 2.1 contains additional guidance on screening the following:
- Consumables
- Multiple intended functions
If the reviewer does not identify any omissions of components from those that are subject to an AMR, the staff would have reasonable assurance that the applicant has identified the components subject to an AMR for the electrical and I&C systems.
2.5.4 Evaluation Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provisions of the SRP-LR and that the staff's evaluation supports conclusions of the following type, to be included in the safety evaluation report:
The staff concludes that there is reasonable assurance that the applicant has appropriately identified the electrical and instrumentation and controls system components subject to an aging management review in accordance with the requirements stated in 10 CFR 54.21(a)(1).
2.5.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specific portions of NRC regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
2.5.6 References
1. SAND96-0344, "Aging Management Guideline for Commercial Nuclear Power Plants-Electrical Cable and Terminations," Sandia National Laboratories, September 1996, page 6-11.
Table 2.5-1. Examples of "Plant Spaces" Approach for Electrical and I&C Scoping and Corresponding Review Procedures
| Example | Review Procedures |
|---|---|
| An applicant indicates that all electrical and I&C components on site are within the scope of license renewal. | This is acceptable, and a staff review is not necessary because all electrical and I&C components are included without exception and would include those required by the rule. |
| An applicant indicates that all electrical and I&C components located in seven specific buildings (containment, auxiliary building, turbine building, etc.) are within the scope of license renewal. | The reviewer should review electrical systems and components in areas outside of these seven buildings ("plant spaces"). The reviewer should verify that the applicant has included any direct-buried cables in trenches between these building as within the scope of license renewal if they perform an intended function. The reviewer should also select buildings other than the seven indicated (for example, the radwaste facility) to verify that they do not contain any electrical and I&C components that perform any intended functions. |
| An applicant indicates that all electrical and I&C components located on site, except for the 525 kV switchyard, 230 kV transmission lines, radwaste facility, and 44 kV substation, are within the scope of license renewal. | The reviewer should select the specifically excluded "plant spaces" (that is, the 525 kV switchyard, 230 kV transmission lines, radwaste facility, and 44 kV substation) to verify that they do not contain any electrical and I&C components that perform any intended functions. |
Chapter 3: Aging Management Review Results
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3.1 Aging Management of Reactor Vessel, Internals, and Reactor Coolant System
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Review Responsibilities
Primary - Branch responsible for materials and chemical engineering
Secondary - Branch responsible for mechanical engineering
3.1.1 Areas of Review
This review plan section addresses the aging management review (AMR) of the reactor vessel, internals, and reactor coolant system. For a recent vintage plant, the information related to the reactor vessel, internals, and reactor coolant system is contained in Chapter 5, "Reactor Coolant System and Connected Systems," of the plant's final safety analysis report (FSAR), consistent with the Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants (NUREG-0800) (Ref. 1). For older plants, the location of applicable information is plant-specific because their FSAR may have predated NUREG-0800.
The reactor vessel, internals, and reactor coolant system includes the reactor vessel and internals. Also included for BWRs are the reactor coolant recirculation system and portions of other systems connected to the pressure vessel extending to the first isolation valve outside of containment or to the first anchor point. These connected systems include residual heat removal, low-pressure core spray, high-pressure core spray, low-pressure coolant injection, high-pressure coolant injection, reactor core isolation cooling, isolation condenser, reactor coolant cleanup, feedwater, and main steam. For PWRs, the reactor coolant system includes the primary coolant loop, the pressurizer and pressurizer relief tank, and the steam generators. The connected systems for PWRs include the residual heat removal or low pressure injection system, core flood spray or safety injection tank, chemical and volume control system or high pressure injection system, and sampling system.
The staff has issued a generic aging lessons learned (GALL) report addressing aging management for license renewal (Ref. 2). The GALL report documents the staff's basis for determining whether generic existing programs are adequate to manage aging without change or generic existing programs should be augmented for license renewal. The GALL report may be referenced in a license renewal application and should be treated in the same manner as an approved topical report.
Because a license renewal applicant may or may not be able to reference the GALL report as explained below, the following areas are reviewed.
3.1.1.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
The applicant may reference the GALL report in a license renewal application to demonstrate that the programs at its facility correspond to those reviewed and approved in the report and that no further staff review is required. If the material presented in the GALL report is applicable to the applicant's facility, the staff should find the applicant's reference to the report acceptable. In making this determination, the staff should consider whether the applicant has identified specific programs described and evaluated in the GALL report. The staff, however, should not repeat its review of the substance of the matters described in the report. Rather, the staff should confirm that the applicant verifies that the approvals set forth in the GALL report for generic programs apply to the applicant's programs.
3.1.1.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report provides the basis for identifying those programs that warrant further evaluation during the staff review of a license renewal application. The staff review focus should be on augmented programs for license renewal.
3.1.1.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
The GALL report provides a generic staff evaluation of certain aging management programs (AMPs). If the applicant does not rely on a particular program for license renewal, or if the applicant indicates that the generic staff evaluation of the elements of a particular program does not apply to its plant, the staff should review each such AMP to which the GALL report does not apply.
The GALL report provides a generic staff evaluation of programs for certain components and aging effects. If the applicant has identified particular components subject to aging management review (AMR) for its plant that are not addressed in the GALL report, or particular aging effects for a component that are not addressed in the GALL report, the staff should review the applicant's AMPs applicable to these particular components and aging effects.
3.1.1.4 FSAR Supplement
The FSAR supplement summarizing the programs and activities for managing the effects of aging for the period of extended operation is reviewed.
3.1.2 Acceptance Criteria
The acceptance criteria for the areas of review describe methods for determining whether the applicant has met the requirements of the NRC's regulations in 10 CFR 54.21.
3.1.2.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
Acceptable methods for managing aging of the reactor vessel, internals, and reactor coolant system are described and evaluated in Chapter IV of the GALL report (Ref. 2). In referencing this report, the applicant should indicate that the material presented is applicable to the specific plant involved and should provide the information necessary to adopt the finding of program acceptability as described and evaluated in the report. The applicant should also verify that the approvals set forth in the GALL report for generic programs apply to the applicant's programs. The applicant may reference appropriate programs as described and evaluated in the GALL report.
3.1.2.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report indicates that further evaluation should be performed for the following.
3.1.2.2.1 Cumulative Fatigue Damage (BWR/PWR)
Fatigue is a time-limited aging analysis (TLAA) as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c)(1). The evaluation of this TLAA is addressed separately in Section 4.3.
3.1.2.2.2 Loss of Material due to Pitting and Crevice Corrosion (BWR/PWR)
1. Loss of material due to pitting and crevice corrosion could occur in the PWR steam generator shell assembly. The existing program relies on control of chemistry to mitigate corrosion and ISI to detect loss of material. The extent and schedule of the existing steam generator inspections are designed to ensure that flaws cannot attain a depth sufficient to threaten the integrity of the welds. However, according to NRC Information Notice (IN) 90-04 (Ref. 4), if general corrosion pitting of the shell exists, the program may not be sufficient to detect pitting and corrosion. The GALL report recommends augmented inspection to manage this aging effect. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
2. Loss of material due to pitting and crevice corrosion could occur in BWR isolation condenser components. The existing program relies on control of reactor water chemistry to mitigate corrosion and on ASME Section XI inservice inspection (ISI). However, the existing program should be augmented to detect loss of material due to pitting or crevice corrosion. The GALL report recommends an augmented program to include temperature and radioactivity monitoring of the shell-side water, and eddy current testing of tubes to ensure that the component's intended function will be maintained during the period of extended operation. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.1.2.2.3 Loss of Fracture Toughness due to Neutron Irradiation Embrittlement (BWR/PWR)
1. Certain aspects of neutron irradiation embrittlement are TLAAs as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c)(1). The evaluation of this TLAA is addressed separately in Section 4.2.
2. Loss of fracture toughness due to neutron irradiation embrittlement could occur in the reactor vessel. A reactor vessel materials surveillance program monitors neutron irradiation embrittlement of the reactor vessel. Reactor vessel surveillance programs are plant specific, depending on matters such as the composition of limiting materials, availability of surveillance capsules, and projected fluence levels. In accordance with 10 CFR Part 50, Appendix H, an applicant is required to submit its proposed withdrawal schedule for approval prior to implementation. Thus, further staff evaluation is required for license renewal. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3. Loss of fracture toughness due to neutron irradiation embrittlement and void swelling could occur in Westinghouse and B&W baffle/former bolts. The GALL report recommends further evaluation to ensure that this aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.1.2.2.4 Crack Initiation and Growth due to Thermal and Mechanical Loading or Stress Corrosion Cracking (BWR/PWR)
1. Crack initiation and growth due to thermal and mechanical loading or SCC (including intergranular stress corrosion cracking [IGSCC]) could occur in small-bore reactor coolant system and connected system piping less than NPS 4. The existing program relies on ASME Section XI ISI and on control of water chemistry to mitigate SCC. The GALL report recommends that a plant-specific destructive examination or a nondestructive examination (NDE) that permits inspection of the inside surfaces of the piping be conducted to ensure that cracking has not occurred and the component intended function will be maintained during the extended period. The AMPs should be augmented by verifying that service-induced weld cracking is not occurring in the small-bore piping less than NPS 4, including pipe, fittings, and branch connections. A one-time inspection of a sample of locations is an acceptable method to ensure that the aging effect is not occurring and the component's intended function will be maintained during the period of extended operation.
2. Crack initiation and growth due to thermal and mechanical loading or SCC (including IGSCC) could occur in BWR reactor vessel flange leak detection line and BWR jet pump sensing line. The GALL report recommends that a plant specific aging management program be evaluated to mitigate or detect crack initiation and growth due to SCC of vessel flange leak detection line. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3. Crack initiation and growth due to thermal and mechanical loading or SCC (including IGSCC) could occur in BWR isolation condenser components. The existing program relies on control of reactor water chemistry to mitigate SCC and on ASME Section XI inservice inspection (ISI). However, the existing program should be augmented to detect cracking due to SCC or cyclic loading. The GALL report recommends an augmented program to include temperature and radioactivity monitoring of the shell-side water, and eddy current testing of tubes to ensure that the component's intended function will be maintained during the period of extended operation.
3.1.2.2.5 Crack Growth due to Cyclic Loading (PWR)
Crack growth due cyclic loading could occur in reactor vessel shell and reactor coolant system piping and fittings. Growth of intergranular separations (underclad cracks) in low-alloy or carbon steel heat affected zone under austenitic stainless steel cladding is a time-limited aging analysis (TLAA) to be evaluated for the period of extended operation for all the SA 508-Cl 2 forgings where the cladding was deposited with a high heat input welding process. The methodology for evaluating the underclad flaw should be consistent with the current well-established flaw evaluation procedure and criterion in the ASME Section XI Code. See the Standard Review Plan, Section 4.7, "Other Plant-Specific Time-Limited Aging Analysis," for generic guidance for meeting the requirements of 10 CFR 54.21(c).
3.1.2.2.6 Changes in Dimension due to Void Swelling (PWR)
Changes in dimension due to void swelling could occur in reactor internal components. The GALL report recommends further evaluation to ensure that this aging effect is adequately managed. The reactor vessel internals receive a visual inspection (VT-3) according to Category B-N-3 of Subsection IXB, ASME Section XI. This inspection is not sufficient to detect the effects of changes in dimension due to void swelling. GALL recommends that a plant-specific aging management program should be evaluated. The applicant provides a plant-specific AMP or participates in industry programs to investigate aging effects and determine appropriate AMP. Otherwise, the applicant provides the basis for concluding that void swelling is not an issue for the component. The applicant should either provide the basis for concluding that void swelling is not an issue for the component or provide a program to manage the effects of changes in dimension due to void swelling and the loss of ductility associated with swelling.
3.1.2.2.7 Crack Initiation and Growth due to Stress Corrosion Cracking or Primary Water Stress Corrosion Cracking (PWR)
1. Crack initiation and growth due to SCC and primary water stress corrosion cracking (PWSCC) could occur in PWR core support pads (or core guide lugs), instrument tubes (bottom head penetrations), pressurizer spray heads, and nozzles for the steam generator instruments and drains. The GALL report recommends further evaluation to ensure that these aging effects are adequately managed. The GALL report recommends that a plant-specific aging management program be evaluated because existing programs may not be capable of mitigating or detecting crack initiation and growth due to SCC. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
2. Crack initiation and growth due to SCC could occur in PWR cast austenitic stainless steel (CASS) reactor coolant system piping and fittings and pressurizer surge line nozzle. The GALL report recommends further evaluation of piping that does not meet either the reactor water chemistry guidelines of TR-105714 or material guidelines of NUREG-0313 (Ref. 5). Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3. Crack initiation and growth due to PWSCC could occur in PWR pressurizer instrumentation penetrations and heater sheaths and sleeves made of Ni alloys. The existing program relies on ASME Section XI ISI and on control of water chemistry to mitigate PWSCC. However, the existing program should be augmented to manage the effects of SCC on the intended function of Ni-alloy components. The GALL report recommends that the applicant provide a plant-specific AMP or participate in industry programs to determine appropriate AMP for PWSCC of Inconel 182 weld. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.1.2.2.8 Crack Initiation and Growth due to Stress Corrosion Cracking or Irradiation-Assisted Stress Corrosion Cracking (PWR)
Crack initiation and growth due to SCC or IASCC could occur in baffle/former bolts in Westinghouse and B&W reactors. Historically the VT-3 visual examinations have not identified baffle/former bolt cracking because cracking occurs at the juncture of the bolt head and shank, which is not accessible for visual inspection. However, recent UT examinations of the baffle/former bolts at several plants have identified cracking. The industry is currently addressing the issue of baffle bolt cracking in the PWR Materials Reliability Project, Issues Task Group (ITG) activities to determine, develop, and implement the necessary steps and plans to manage the applicable aging effects on a plant-specific basis. The GALL report recommends further evaluation to ensure that these aging effects are adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.1.2.2.9 Loss of Preload due to Stress Relaxation (PWR)
Loss of preload due to stress relaxation could occur in baffle/former bolts in Westinghouse and B&W reactors. Visual inspection (VT-3) should be augmented to detect relevant conditions of stress relaxation because only the heads of the baffle/former bolts are visible, and a plant-specific aging management program is thus required. The GALL report recommends a plant-specific aging management program to ensure that these aging effects are adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.1.2.2.10 Loss of Section Thickness due to Erosion (PWR)
Loss of section thickness due to erosion could occur in steam generator feedwater impingement plates and supports. The GALL report recommends further evaluation of a plant-specific aging management program to ensure that this aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.1.2.2.11 Crack Initiation and Growth due to PWSCC, ODSCC, or Intergranular Attack or Loss of Material due to Wastage and Pitting Corrosion or Loss of Section Thickness due to Fretting and Wear or Denting due to Corrosion of Carbon Steel Tube Support Plate (PWR)
Crack initiation and growth due to PWSCC, ODSCC, or intergranular attack (IGA) or loss of material due to wastage and pitting corrosion or deformation due to corrosion could occur in alloy 600 components of the steam generator tubes, repair sleeves and plugs. All PWR licensees have committed voluntarily to a SG degradation management program described in NEI 97-06; these guidelines are currently under NRC staff review. The GALL report recommends that an AMP based on the recommendations of staff-approved NEI 97-06 guidelines, or other alternate regulatory basis for SG degradation management, should be developed to ensure that this aging effect is adequately managed.
3.1.2.2.12 Loss of Section Thickness due to Flow-accelerated Corrosion
Loss of section thickness due to flow-accelerated corrosion could occur in tube support lattice bars made of carbon steel. The GALL report recommends that a plant-specific aging management program be evaluated and, on the basis of the guidelines of NRC Generic Letter 97-06, an inspection program for steam generator internals be developed to ensure that this aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.1.2.2.13 Ligament Cracking due to Corrosion (PWR)
Ligament cracking due to corrosion could occur in carbon steel components in the steam generator tube support plate. All PWR licensees have committed voluntarily to a SG degradation management program described in NEI 97-06; these guidelines are currently under NRC staff review. The GALL report recommends that an AMP based on the recommendations of staff-approved NEI 97-06 guidelines, or other alternate regulatory basis for SG degradation management, be developed to ensure that this aging effect is adequately managed.
3.1.2.2.14 Loss of Material due to Flow-accelerated Corrosion (PWR)
Loss of material due to flow-accelerated corrosion could occur in feedwater inlet ring and supports. As noted in Combustion Engineering (CE) Information Notice (IN) 90-04 and NRC IN 91-19 and LER 50-362/90-05-01, this form of degradation has been detected only in certain CE System 80 steam generators. The GALL report recommends further evaluation to ensure that this aging effect is adequately managed. The GALL report recommends that a plant-specific aging management program be evaluated because existing programs may not be capable of mitigating or detecting loss of material due to flow-accelerated corrosion. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.1.2.2.15 Quality Assurance for Aging Management of Nonsafety-Related Components
Acceptance criteria are described in Branch Technical Position IQMB-1 (Appendix A.2 of this standard review plan).
3.1.2.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.1.2.4 FSAR Supplement
The summary description of the programs and activities for managing the effects of aging for the period of extended operation in the FSAR supplement should be appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the bases for determining that aging effects will be managed during the period of extended operation.
3.1.3 Review Procedures
For each area of review, the following review procedures are to be followed.
3.1.3.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
The applicant may reference the GALL report in its license renewal application, as appropriate. The staff should not repeat its review of the substance of the matters described in the report. If the applicant has provided the information necessary to adopt the finding of program acceptability as described and evaluated in the GALL report, the staff should find the applicant's reference to the report in a license renewal application acceptable. In making this determination, the reviewer verifies that the applicant has provided a brief description of the system, components, materials, and environment. The reviewer also verifies that the applicant has stated that the applicable aging effects and industry and plant-specific operating experience have been reviewed by the applicant and are evaluated in the GALL report. The reviewer verifies that the applicant has identified those aging effects for the reactor vessel, internals, and reactor coolant system components that are contained in the report as applicable to its plant. In addition, the reviewer ensures that the applicant has stated that the plant programs covered by the applicant's reference contain the same program elements that the staff evaluated and relied upon in approving the corresponding generic program in the GALL report.
The reviewer should verify that the applicant has stated that certain of its
AMPs contain the same program elements as the corresponding generic program described
in the GALL report and upon which the staff relied in its evaluation. The reviewer
should also verify that the applicant has stated that the GALL report is applicable
to its plant with respect to these programs. The reviewer verifies that the applicant
has identified the appropriate programs as described and evaluated in the GALL
report. Programs evaluated in the report regarding the reactor vessel, internals,
and reactor coolant system components are summarized in
Table 3.1-1 of this review plan. No further staff evaluation is necessary if
so recommended in the GALL report.
3.1.3.2 Further Evaluation of Aging Management as Recommended by the GALL Report
3.1.3.2.1 Cumulative Fatigue Damage (BWR/PWR)
Fatigue is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c)(1). The staff reviews the evaluation of this TLAA separately following the guidance in Section 4.3 of this standard review plan.
3.1.3.2.2 Loss of Material due to Pitting and Crevice Corrosion (BWR/PWR)
1. The GALL report recommends further evaluation for the management of loss of material due to pitting and crevice corrosion of the PWR steam generator shell assembly. The existing program relies on control of reactor water chemistry to mitigate corrosion and on ISI for detection. Based on NRC IN 90-04 (Ref. 4), if general corrosion pitting of the shell exists, the existing program requirements may not be sufficient to detect loss of material due to pitting and corrosion, and additional inspection procedures may be required. The reviewer verifies on a case-by-case basis that the applicant has proposed a program that will manage loss of material due to pitting and crevice corrosion by providing enhanced inspection and supplemental methods to detect loss of material and ensure that the component intended function will be maintained during the extended period.
2. The GALL report recommends an augmented program to include temperature and radioactivity monitoring of the shell-side water and eddy current testing of tubes for the management of loss of material due to pitting and crevice corrosion in BWR isolation condenser components. The existing program relies on control of reactor water chemistry to mitigate corrosion and on ASME Section XI ISI for detection. However, the inspection requirements should be augmented to detect loss of material due to pitting and crevice corrosion, and an augmented program to include temperature and radioactivity monitoring of the shell-side water and eddy current testing of tubes is recommended to ensure that the component's intended function will be maintained during the period of extended operation. The reviewer verifies on a case-by-case basis that the applicant has proposed an augmented program that will manage loss of material due to pitting and crevice corrosion and ensure that the component intended function will be maintained during the extended period.
3.1.3.2.3 Loss of Fracture Toughness due to Neutron Irradiation Embrittlement (BWR/PWR)
1. Neutron irradiation embrittlement is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c)(1). The staff reviews the evaluation of this TLAA following the guidance in Section 4.2 of this standard review plan.
2. The GALL report recommends further evaluation of the reactor vessel materials surveillance program for the period of extended operation. Neutron embrittlement of the reactor vessel is monitored by a reactor vessel materials surveillance program. Reactor vessel surveillance programs are plant specific, depending on matters such as the composition of limiting materials, availability of surveillance capsules, and projected fluence levels. In accordance with 10 CFR Part 50, Appendix H, an applicant must submit its proposed withdrawal schedule for approval prior to implementation. Thus, further staff evaluation is required for license renewal. The reviewer verifies on a case-by-case basis that the applicant has proposed an adequate reactor vessel materials surveillance program for the period of extended operation. Specific criteria for an acceptable AMP is provided in chapter XI, Section M31 of the GALL report.
3. The GALL report recommends further evaluation for the management of loss of fracture toughness due to neutron irradiation embrittlement and void swelling of Westinghouse and B&W baffle/former bolts. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3.1.3.2.4 Crack Initiation and Growth due to Thermal and Mechanical Loading or Stress Corrosion Cracking (BWR/PWR)
1. The GALL report recommends a plant-specific destructive examination or a nondestructive examination (NDE) that permits inspection of the inside surfaces of the piping for the management of crack initiation and growth due to thermal and mechanical loading or SCC of small-bore reactor coolant system and connected system piping (less than NPS 4). The existing program should be augmented by verifying that service-induced weld cracking is not occurring in the small-bore piping less than NPS 4, including pipe, fittings, and branch connections. See Chapter XI.M32, "One-Time Inspection" for an acceptable verification method. The GALL report recommends that the inspection include a representative sample of the system population, and, where practical and prudent, focus on the bounding or lead components most susceptible to aging due to time in service, severity of operating conditions, and lowest design margin. For small-bore piping, actual inspection locations should be based on physical accessibility, exposure levels, NDE examination techniques, and locations identified in Nuclear Regulatory Commission (NRC) Information Notice (IN) 97-46. Combinations of NDE, including visual, ultrasonic, and surface techniques, are performed by qualified personnel following procedures consistent with the ASME Code and 10 CFR 50 Appendix B. For small-bore piping less than NPS 4 in., including pipe, fittings, and branch connections, a plant-specific destructive examination or NDE that permits inspection of the inside surfaces of the piping should be conducted to ensure that cracking has not occurred. Follow-up of unacceptable inspection findings should include expansion of the inspection sample size and locations. The inspection and test techniques prescribed by the program should verify any aging effects because these techniques, used by qualified personnel, have been proven effective and consistent with staff expectations. The staff reviews to confirm that the program includes measures to verify that unacceptable degradation is not occurring, thereby validating the effectiveness of existing programs or confirming that there is no need to manage aging-related degradation for the period of extended operation. If an applicant proposes a one-time inspection of select components and susceptible locations to ensure that corrosion is not occurring, the reviewer verifies that the proposed inspection will be performed using techniques similar to ASME Code and ASTM standards including visual, ultrasonic, and surface techniques (Refs. 6 and 7) to ensure that the component's intended function will be maintained during the period of extended operation.
2. The GALL report recommends that a plant specific aging management program be evaluated for the management of crack initiation and growth due to thermal and mechanical loading or SCC (including IGSCC) in BWR reactor vessel flange leak detection line and BWR jet pump sensing line. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3. The GALL report recommends an augmented program to include temperature and radioactivity monitoring of the shell-side water, and eddy current testing of tubes for the management of crack initiation and growth due to thermal and mechanical loading or SCC (including IGSCC) of the BWR isolation condenser components. The existing program relies on control of reactor water chemistry to mitigate SCC and on ASME Section XI inservice inspection (ISI) to detect leakage. However, the existing program should be augmented to detect cracking due to SCC or cyclic loading. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3.1.3.2.5 Crack Growth due to Cyclic Loading (PWR)
The GALL report recommends further evaluation of programs to manage crack growth due to cyclic loading in reactor vessel shell and reactor coolant system piping and fittings. Growth of intergranular separations (underclad cracks) in low-alloy or carbon steel heat affected zone under austenitic stainless steel cladding is a time-limited aging analysis (TLAA) to be evaluated for the period of extended operation for all the SA 508-Cl 2 forgings where the cladding was deposited with a high heat input welding process. The methodology for evaluating the underclad flaw should be consistent with the current well-established flaw evaluation procedure and criterion in the ASME Section XI Code. The Standard Review Plan, Section 4.7, "Other Plant-Specific Time-Limited Aging Analysis," provides generic guidance for meeting the requirements of 10 CFR 54.21(c). The staff reviews the evaluation of this TLAA separately following the guidance in Section 4.7 of this standard review plan.
3.1.3.2.6 Changes in Dimension due to Void Swelling (PWR)
The GALL report recommends further evaluation of programs to manage changes in dimension due to void swelling for reactor internal components. Changes in dimension due to void swelling could occur in reactor internal components. The GALL report recommends further evaluation to ensure that this aging effect is adequately managed. The reactor vessel internals receive a visual inspection (VT-3) according to Category B-N-3 of Subsection IWB, ASME Section XI. This inspection is not sufficient to detect the effects of changes in dimension due to void swelling. The GALL report recommends further evaluation of a plant-specific aging management program. The applicant should provide a plant-specific AMP or participate in industry programs to investigate aging effects and determine an appropriate AMP. Otherwise, the applicant should provide the basis for concluding that void swelling is not an issue for the component. The applicant should either provide the basis for concluding that void swelling is not an issue for the component or provide a program to manage the effects of changes in dimension due to void swelling and the loss of ductility associated with swelling. The reviewer verifies on a case-by-case basis that the applicant has either proposed a program to manage changes in dimension due to void swelling in the pressure vessel internal components or provided the basis for concluding that void swelling is not an issue.
3.1.3.2.7 Crack Initiation and Growth due to Stress Corrosion Cracking or Primary Water Stress Corrosion Cracking (PWR)
1. The GALL report recommends that a plant-specific aging management program is to be evaluated to manage crack initiation and growth due to SCC and primary water stress corrosion cracking (PWSCC) in PWR core support pads (or core guide lugs, instrument tubes (bottom head penetrations), pressurizer spray heads, and nozzles for the steam generator instruments and drains. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
2. The GALL report recommends further evaluation of programs to manage crack initiation and growth due to SCC of PWR cast austenitic stainless steel (CASS) reactor coolant system piping and fittings and pressurizer surge line nozzle. The GALL report recommends further evaluation of piping that does not meet either the reactor water chemistry guidelines of TR-105714 or material guidelines of NUREG-0313 (Ref. 5). The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3. The GALL report recommends further evaluation of programs to manage crack initiation and growth due to PWSCC of PWR pressurizer instrumentation penetrations and heater sheaths and sleeves made of Ni alloys. The existing program relies on ASME Section XI ISI to detect cracks and on control of water chemistry to mitigate PWSCC. However, the program should be augmented to manage the effects of SCC on the intended function of Ni-alloy components. The GALL report recommends the applicant provides a plant-specific AMP or participate in industry programs to determine appropriate AMP for PWSCC of Inconel 182 weld. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3.1.3.2.8 Crack Initiation and Growth due to Stress Corrosion Cracking or Irradiation-Assisted Stress Corrosion Cracking (PWR)
The GALL report recommends further evaluation of crack initiation and growth due to SCC or IASCC in Westinghouse and B&
3.1.3.2.9 Loss of Preload due to Stress Relaxation (PWR)
The GALL report recommends further evaluation of loss of preload due to stress relaxation could occur in baffle/former bolts in Westinghouse and B&
3.1.3.2.10 Loss of Section Thickness due to Erosion (PWR)
3.1.3.2.12 Loss of Section Thickness due to Flow-accelerated Corrosion
3.1.3.2.13 Ligament Cracking due to Corrosion (PWR)
3.1.3.2.14 Loss of material due to Flow-accelerated Corrosion (PWR)
3.1.3.4 FSAR Supplement
3.1.3.3, ""
CFR 50.59.
3.1.4 Evaluation Findings
3.1.5 Implementation
3.1.6 References
1. NUREG-0800, "" U.S. Nuclear Regulatory Commission, July 1981.
2. NUREG-1801, "Generic Aging Lessons Learned (GALL),"
3. NEI 97-06, "Steam Generator Program Guidelines," Nuclear Energy Institute, December 1997.
4. NRC Information Notice 90-04, ""
5. NUREG-0313, Rev. 2, "
6. EPRI TR-107569-V1R5, ""
7. NRC Regulatory Guide 1.83, "" U.S. Nuclear Regulatory Commission, June 1974.
8. NRC Regulatory Guide 1.121, "" U.S. Nuclear Regulatory Commission, May 1976.
9. NRC Generic Letter 95-05, ""
10. NRC Information Notice 90-10, ""
11. NRC Information Notice 90-30, ""
12. NRC Generic Letter 89-08, "Erosion/Corrosion-Induced Pipe Wall Thinning," May 2, 1989.
13. NSAC-202L-R2, "" Electric Power Research Institute, April 1999.
14. NRC Information Notice 96-11, "" February 14, 1996.
15. NRC Generic Letter 97-06, "Degradation of Steam Generator Internals,"
16. BWRVIP-29 (EPRI TR-103515),
17. EPRI NP-5769,
18. EPRI TR-105714,
19. NRC Generic Letter 88-01, January 25, 1988.
20. NRC Generic Letter 97-01, April 1,1997.
21. NRC Information Notice 97-46, July 9, 1997.
22. NRC Regulatory Guide 1.99, Rev. 2, May 1988.
23. NUREG-0619,
24. NUREG-1339, Resolution of Generic Safety Issue 29:
25. EPRI TR-104213, Bolted Joint Maintenance & Application Guide,
26. NEI letter dated Dec. 11, 1998, Dave Modeen to Gus Lainas, "Responses to NRC Requests for Additional Information (RAIs) on GL 97-01."
Table 3.1-1. Summary of Aging Management Programs for Reactor Vessel, Internals, and Reactor Coolant System Evaluated in Chapter IV of the GALL Report
| Type | Component |
Aging Effect/ Mechanism |
Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| BWR/PWR | Reactor coolant pressure boundary components | Cumulative fatigue damage | TLAA, evaluated in accordance with 10 CFR 54.21(c) | Yes, TLAA (See Subsection 3.1.2.2.1) |
| PWR | Steam generator shell assembly | Loss of material due to pitting and crevice corrosion | Inservice inspection; water chemistry | Yes, detection of aging effects is to be further evaluated (See Subsection 3.1.2.2.2.1) |
| BWR | Isolation condenser | Loss of material due to general, pitting, and crevice corrosion | Inservice inspection; water chemistry | Yes, plant specific (See Subsection 3.1.2.2.2.2) |
| BWR/PWR | Pressure vessel ferritic materials that have a neutron fluence greater than 1017 n/cm2 (E>1 MeV) | Loss of fracture toughness due to neutron irradiation embrittlement | TLAA, evaluated in accordance with Appendix G of 10 CFR 50 and RG 1.99 | Yes, TLAA (See Subsection 3.1.2.2.3.1) |
| BWR/PWR | Reactor vessel beltline shell and welds | Loss of fracture toughness due to neutron irradiation embrittlement | Reactor vessel surveillance | Yes, plant specific (See Subsection 3.1.2.2.3.2) |
| PWR | Westinghouse and B&W baffle/former bolts | Loss of fracture toughness due to neutron irradiation embrittlement and void swelling | Plant specific | Yes, plant specific
(See Subsection 3.1.2.2.3.3) |
| BWR/PWR | Small-bore reactor coolant system and connected systems piping | Crack initiation and growth due to SCC, intergranular SCC, and thermal and mechanical loading | Inservice inspection; water chemistry; one-time inspection | Yes, parameters monitored/inspected and detection of aging effects are to be further evaluated (See Subsection 3.1.2.2.4.1) |
| BWR | Jet pump sensing line, and reactor vessel flange leak detection line | Crack initiation and growth due to SCC, intergranular stress corrosion cracking (IGSCC), or cyclic loading | Plant specific | Yes, plant specific
(See Subsection 3.1.2.2.4.2) |
| BWR | Isolation condenser | Crack initiation and growth due to stress corrosion cracking (SCC) or cyclic loading; | Inservice inspection; water chemistry | Yes, plant specific (See Subsection 3.1.2.2.4.3) |
| PWR | Vessel shell | Crack growth due to cyclic loading | TLAA | Yes, TLAA (See Subsection 3.1.2.2.5) |
Table 3.1-1. Summary of Aging Management Programs for Reactor Vessel, Internals, and Reactor Coolant System Evaluated in Chapter IV of the GALL Report (continued)
| Type | Component |
Aging Effect/ Mechanism |
Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| PWR | Reactor internals | Changes in dimension due to void swelling | Plant specific | Yes, plant specific (See Subsection 3.1.2.2.6) |
| PWR | PWR core support pads, instrument tubes (bottom head penetrations), pressurizer spray heads, and nozzles for the steam generator instruments and drains | Crack initiation and growth due to SCC and/or primary water stress corrosion cracking (PWSCC) | Plant specific | Yes, plant specific
(See Subsection 3.1.2.2.7.1) |
| PWR | Cast austenitic stainless steel (CASS) reactor coolant system piping | Crack initiation and growth due to SCC | Plant specific | Yes, plant specific(See Subsection 3.1.2.2.7.2) |
| PWR | Pressurizer instrumentation penetrations and heater sheaths and sleeves made of Ni-alloys | Crack initiation and growth due to PWSCC | Inservice inspection; water chemistry | Yes, AMP for PWSCC of
Inconel 182 weld is to be
evaluated
(See Subsection 3.1.2.2.7.3) |
| PWR | Westinghouse and B&W baffle former bolts | Crack initiation and growth due to SCC and IASCC | Plant specific | Yes, plant specific
(See Subsection 3.1.2.2.8) |
| PWR | Westinghouse and B&W baffle former bolts | Loss of preload due to stress relaxation | Plant specific | Yes, plant specific
(See Subsection 3.1.2.2.9) |
| PWR | Steam generator feedwater impingement plate and support | Loss of section thickness due to erosion | Plant specific | Yes, plant specific
(See Subsection 3.1.2.2.10) |
| PWR | (Alloy 600) Steam generator tubes, repair sleeves, and plugs | Crack initiation and growth due to PWSCC, outside diameter stress corrosion cracking (ODSCC), and/or intergranular attack (IGA) or loss of material due to wastage and pitting corrosion, and fretting and wear; or deformation due to corrosion at tube support plate intersections | Steam generator tubing integrity; water chemistry | Yes, effectiveness of a proposed AMP is to be evaluated (See Subsection 3.1.2.2.11) |
| PWR | Tube support lattice bars made of carbon steel | Loss of section thickness due to FAC | Plant specific | Yes, plant specific
(See Subsection 3.1.2.2.12) |
| PWR | Carbon steel tube support plate | Ligament cracking due to corrosion | Plant specific | Yes, effectiveness of a proposed AMP is to be evaluated (See Subsection 3.1.2.2.13) |
| PWR (CE) | Steam generator feedwater inlet ring and supports | Loss of material due to flow-corrosion | Combustion engineering (CE) steam generator feedwater ring inspection | Yes, plant specific
(See Subsection 3.1.2.2.14) |
| BWR/PWR | Reactor vessel closure studs and stud assembly | Crack initiation and growth due to SCC and/or IGSCC | Reactor head closure studs | No |
| BWR/PWR | CASS pump casing and valve body | Loss of fracture toughness due to thermal aging embrittlement | Inservice inspection | No |
| BWR/PWR | CASS piping | Loss of fracture toughness due to thermal aging embrittlement | Thermal aging embrittlement of CASS | No |
| BWR/PWR | BWR piping and fittings; steam generator components | Wall thinning due to flow-accelerated corrosion | Flow-accelerated corrosion | No |
| BWR/ PWR |
Reactor coolant pressure boundary (RCPB) valve closure bolting, manway and holding bolting, and closure bolting in high pressure and high temperature systems | Loss of material due to wear; loss of preload due to stress relaxation; crack initiation and growth due to cyclic loading and/or SCC | Bolting integrity | No |
| BWR | Feedwater and control rod drive (CRD) return line nozzles | Crack initiation and growth due to cyclic loading | Feedwater nozzle; CRD return line nozzle | No |
| BWR | Vessel shell attachment welds | Crack initiation and growth due to SCC, IGSCC | BWR vessel ID attachment welds; water chemistry | No |
| BWR | Nozzle safe ends, recirculation pump casing, connected systems piping and fittings, body and bonnet of valves | Crack initiation and growth due to SCC, IGSCC | BWR stress corrosion cracking; water chemistry | No |
| BWR | Penetrations | Crack initiation and growth due to SCC, IGSCC, cyclic loading | BWR penetrations; water chemistry | No |
| BWR | Core shroud and core plate, support structure, top guide, core spray lines and spargers, jet pump assemblies, control rod drive housing, nuclear instrumentation guide tubes | Crack initiation and growth due to SCC, IGSCC, IASCC | BWR vessel internals; water chemistry | No |
| BWR | Core shroud and core plate access hole cover (welded and mechanical covers) | Crack initiation and growth due to SCC, IGSCC, IASCC | ASME Section XI inservice inspection; water chemistry | No |
| BWR | Jet pump assembly castings; orificed fuel support | Loss of fracture toughness due to thermal aging and neutron embrittlement | Thermal aging and neutron irradiation embrittlement | No |
| BWR | Unclad top head and nozzles | Loss of material due to general, pitting, and crevice corrosion | Inservice inspection; water chemistry | No |
| PWR | CRD nozzle | Crack initiation and growth due to PWSCC | Ni-alloy nozzles and penetrations; water chemistry | No |
| PWR | Reactor vessel nozzles safe ends and CRD housing; reactor coolant system components (except CASS and bolting) | Crack initiation and growth due to cyclic loading, and/or SCC, and PWSCC | Inservice inspection; water chemistry | No |
| PWR | Reactor vessel internals CASS components | Loss of fracture toughness due to thermal aging, neutron irradiation embrittlement, and void swelling | Thermal aging and neutron irradiation embrittlement | No |
| PWR | External surfaces of carbon steel components in reactor coolant system pressure boundary | Loss of material due to boric acid corrosion | Boric acid corrosion | No |
| PWR | Steam generator secondary manways and handholds (CS) | Loss of material due to erosion | Inservice inspection | No |
| PWR | Reactor internals, reactor vessel closure studs, and core support pads | Loss of material due to wear | Inservice inspection | No |
| PWR | Pressurizer integral support | Crack initiation and growth due to cyclic loading | Inservice inspection | No |
| PWR | Upper and lower internals
assembly
(Westinghouse) |
Loss of preload due to stress relaxation | Inservice inspection; loose part and/or neutron noise monitoring | No |
| PWR | Reactor vessel internals in fuel zone region (except Westinghouse and Babcock & Wilcox [B&W] baffle bolts) | Loss of fracture toughness due to neutron irradiation embrittlement, and void swelling | PWR vessel internals; water chemistry | No |
| PWR | Steam generator upper and
lower heads; tubesheets; primary nozzles and safe ends |
Crack initiation and growth due to SCC, PWSCC. IASCC | Inservice inspection; water chemistry |
No |
| PWR | Vessel internals (except Westinghouse and B&W baffle former bolts) | Crack initiation and growth due to SCC and IASCC | PWR vessel internals; water chemistry | No |
| PWR | Reactor internals (B&W screws and bolts) | Loss of preload due to stress relaxation | Inservice inspection; loose part monitoring | No |
| PWR | Reactor vessel closure studs and stud assembly | Loss of material due to wear | Reactor head closure studs | No |
| PWR | Reactor internals (Westinghouse upper and lower internal assemblies; CE bolts and tie rods) | Loss of preload due to stress relaxation | Inservice inspection; loose part monitoring | No |
Table 3.1-2. FSAR Supplement for Aging Management of Reactor Vessel, Internals, and Reactor Coolant System
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| ISI | The program consists of periodic volumetric, surface, and/or visual examination of components and their supports for assessment, signs of degradation, and corrective actions. This program is in accordance with ASME Section XI, 1995 edition through the 1996 addenda. | Existing program |
| Water chemistry | To mitigate aging effects on component surfaces that are exposed to water as process fluid, chemistry programs are used to control water chemistry for impurities (e.g., chloride, fluoride, and sulfate) that accelerate corrosion. This program relies on monitoring and control of water chemistry to keep peak levels of various contaminants below the system-specific limits based on EPRI guidelines of TR-103515 for water chemistry in BWRs, TR-105714 for primary water chemistry in PWRs, and TR-102134 for secondary water chemistry in PWRs. | Existing program |
| One-time inspection | To verify the effectiveness of the water chemistry control program by determining if the aging effect is not occurring or the aging effect is progressing slowly so that the that the intended function will be maintained during the period of extended operation, a one-time inspection of small-bore piping less than NPS 4, including pipe, fittings, and branch connections, using suitable techniques at the most susceptible locations is performed. Actual inspection locations should be based on physical accessibility, exposure levels, and NDE techniques, and locations identified in NRC IN 97-46. | Inspection should be completed before the period of extended operation. |
| Bolting integrity | This program consists of guidelines on materials selection, strength and hardness properties, installation procedures, lubricants and sealants, corrosion considerations in the selection and installation of pressure-retaining bolting for nuclear applications, and enhanced inspection techniques. This program relies on the bolting integrity program delineated in NUREG-1339 and industry's recommendations delineated in EPRI NP-5769, with the exceptions noted in NUREG-1339 for safety-related bolting and in EPRI TR-104213 for pressure retaining bolting and structural bolting. | Existing program |
Table 3.1-2. FSAR Supplement for Aging Management of Reactor Vessel, Internals, and Reactor Coolant System (continued)
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Reactor vessel surveillance | Periodic testing of metallurgical surveillance samples is used to monitor the progress of neutron embrittlement of the reactor pressure vessel as a function of neutron fluence, in accordance with Regulatory Guide (RG) 1.99, Rev. 2. | The surveillance capsule withdrawal schedule should be revised before the period of extended operation. |
| Boric acid corrosion | The program consists of (1) visual inspection of external surfaces that are potentially exposed to borated water leakage, (2) timely discovery of leak path and removal of the boric acid residues, (3) assessment of the damage, and (4) follow-up inspection for adequacy. This program is implemented in response to GL 88-05. | Existing program |
| Thermal aging and neutron irradiation embrittlement of cast austenitic stainless steel | The program consists of (1) determination of the susceptibility of cast austenitic stainless steel components to thermal aging embrittlement, (2) accounting for the synergistic effects of thermal aging and neutron irradiation, and (3) implementing a supplemental examination program, as necessary. | Program should be implemented before the period of extended operation. |
| Reactor Head Closure Studs | This program includes inservice inspection ISI. For boiling water reactors (BWRs), this program also includes additional preventive actions and inspection techniques. | Existing program |
| Flow-accelerated corrosion | The program consists of the following: (1) conduct appropriate analysis and baseline inspection, (2) determine extent of thinning and replace/repair components, and (3) perform follow up inspections to confirm or quantify and take longer-term corrective actions. This program is in response to NRC GL 89-08. | Existing Program |
| Quality assurance | The 10 CFR Part 50, Appendix B program provides for corrective actions, confirmation process, and administrative controls for aging management programs for license renewal. The scope of this existing program will be expanded to include nonsafety-related structures and components that are subject to an AMR for license renewal. | Program should be implemented before the period of extended operation. |
| Vessel closure head penetration | The program assesses degradation of CRD mechanism nozzle and other vessel closure head penetrations, and consists of a review of the scope and schedule of inspection, including the leakage detection system, to assure detection of cracks before the loss of intended function of the penetrations. This is in response to NRC GL 97-01. | Existing program |
| BWR Control Rod Drive Return Line Nozzle | The AMP monitors the effects of cracking on the intended function of the component by detection and sizing of cracks by ISI in accordance with the NUREG-0619 and alternative recommendation of GE NE-523-A71-0594. NUREG-0619 specifies UT of the entire nozzle and penetration testing (PT) of varying portions of the blend radius and bore. GE NE-523-A71-0594 specifies UT of specific regions of the blend radius and bore. UT techniques and personnel qualification are according to the guidelines of GE NE-523-A71-0594. | Program should be implemented before the period of extended operation. |
| Steam generator tube integrity | This program consists of SG inspection scope, frequency, acceptance criteria for the plugging and repair of flawed tubes in accordance with the plant technical specifications that includes commitments to NEI 97-06. | Existing program |
| Loose part monitoring | The program consists of loose part monitoring of reactor vessel and primary coolant systems in accordance with ASME OM-S/G-1997 standards. The program addresses methods, intervals, parameters to be measured and evaluated, and records requirements. | Existing program |
| Neutron noise monitoring | The program consists of neutron noise monitoring for the detection of loss of axial preload at the core support barrel's upper support flange, and can detect physical displacement and motion of reactor internals in accordance with ASME OM-S/G-1997 standards. The program addresses methods, intervals, parameters to be measured and evaluated, acceptance criteria, and records requirements. | Existing program |
| BWR Vessel Internals | The program includes (a) inspection and flaw evaluation in conformance with the guidelines of applicable and staff-approved boiling water reactor vessel and internals project (BWRVIP) documents and (b) monitoring and control of reactor coolant water chemistry in accordance with the guidelines of BWRVIP-29 (EPRI TR-103515) to ensure the long-term integrity and safe operation of boiling water reactor (BWR) vessel internal components. | Existing program |
| Plant-specific AMP | The description should contain information associated with the basis for determining that aging effects will be managed during the period of extended operation. | Program should be implemented before the period of extended operation. |
| BWR Vessel ID Attachment Welds | The program includes (a) inspection and flaw evaluation in conformance with the guidelines of staff-approved boiling water reactor vessel and internals project (BWRVIP)-48 and (b) monitoring and control of reactor coolant water chemistry in accordance with the guidelines of BWRVIP-29 (EPRI TR-103515). | |
| BWR Stress Corrosion Cracking | The program to manage intergranular stress corrosion cracking (IGSCC) in boiling water reactor (BWR) coolant pressure boundary piping made of stainless steel (SS) is delineated in NUREG-0313, Rev. 2, and Nuclear Regulatory Commission (NRC) Generic Letter (GL) 88-01 and its Supplement 1. The program includes (a) preventive measures to mitigate IGSCC and (b) inspections to monitor IGSCC and its effects. | Existing program |
| BWR Penetrations | The program includes (a) inspection and flaw evaluation in conformance with the guidelines of staff-approved boiling water reactor vessel and internals project (BWRVIP)-49 and BWRVIP-27 documents and (b) monitoring and control of reactor coolant water chemistry in accordance with the guidelines of BWRVIP-29 (EPRI TR-103515) to ensure the long-term integrity and safe operation of boiling water reactor (BWR) vessel internal components. | Existing program |
| Nickel-Alloy Nozzles and Penetrations | The program includes (a) primary water stress corrosion cracking (PWSCC) susceptibility assessment to identify susceptible components, (b) monitoring and control of reactor coolant water chemistry to mitigate PWSCC, and (c) inservice inspection ISI of reactor vessel head penetrations to monitor PWSCC and its effect on the intended function of the component. For susceptible penetrations and locations, the program includes an industry wide, integrated, long-term inspection program based on the industry responses to NRC Generic Letter (GL) 97-01. | Existing program |
| Thermal Aging of Cast Austenitic Stainless Steel | This program includes (a) determination of the susceptibility of cast austenitic stainless steel components to thermal aging embrittlement and (b) for potentially susceptible components aging management is accomplished through either enhanced volumetric examination or plant- or component-specific flaw tolerance evaluation. | Existing program |
| PWR Vessel Internals | The program includes (a) augmentation of the inservice inspection (ISI) to include enhanced VT-1 examinations of non-bolted components, and other demonstrated acceptable methods for bolted components for certain susceptible or limiting components or locations, and (b) monitoring and control of reactor coolant water chemistry in accordance with the EPRI guidelines in TR-105714 to ensure the long-term integrity and safe operation of pressurized water reactor (PWR) vessel internal components. | Program should be implemented before the period of extended operation. |
| BWR Feedwater Nozzle | This program includes (a) enhancing inservice inspection (ISI) specified in the American Society of Mechanical Engineers (ASME) Code, Section XI, with the recommendation of General Electric (GE) NE-523-A71-0594 to perform periodic ultrasonic testing inspection of critical regions of the BWR feedwater nozzle. | Existing program |
| * An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date. | ||
3.2 Aging Management of Engineered Safety Features
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Review Responsibilities
Primary - Branch responsible for materials and chemical engineering
Secondary - Branch responsible for mechanical engineering
3.2.1 Areas of Review
This review plan section addresses the aging management review (AMR) of the engineered safety features. For a recent vintage plant, the information related to the engineered safety features is contained in Chapter 6, "Engineered Safety Features," of the plant's FSAR, consistent with the "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants" (NUREG-0800) (Ref. 1). The engineered safety features contained in this review plan section are generally consistent with those contained in NUREG-0800 except for the refueling water, control room habitability, and residual heat removal systems. For older plants, the location of applicable information is plant-specific because their FSAR may have predated NUREG-0800. The engineered safety features consist of containment spray, standby gas treatment (BWRs), containment isolation components, and emergency core cooling systems.
The staff has issued a GALL report addressing aging management for license renewal (Ref. 2). The GALL report documents the staff's basis for determining whether generic existing programs are adequate to manage aging without change, or generic existing programs should be augmented for license renewal. The GALL report may be referenced in a license renewal application, and should be treated in the same manner as an approved topical report.
Because a license renewal applicant may or may not be able to reference the GALL report as explained below, the following areas are reviewed:
3.2.1.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
The applicant may reference the GALL report in a license renewal application to demonstrate that the applicant's programs at its facility correspond to those reviewed and approved in the report, and that no further staff review is required. If the material presented in the GALL report is applicable to the applicant's facility, the staff should find the applicant's reference to the report acceptable. In making this determination, the staff should consider whether the applicant has identified specific programs described and evaluated in the GALL report. The staff, however, should not repeat its review of the substance of the matters described in the report. Rather, the staff should ensure that the applicant verifies that the approvals set forth in the GALL report for generic programs apply to the applicant's programs.
3.2.1.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report provides the basis for identifying those programs that warrant further evaluation during the staff review of a license renewal application. The staff review should focus on augmented programs for license renewal.
3.2.1.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
The GALL report provides a generic staff evaluation of certain aging management programs. If the applicant does not rely on a particular program for license renewal, or if the applicant indicates that the generic staff evaluation of the elements of a particular program does not apply to its plant, the staff should review each such aging management program to which the GALL report does not apply.
The GALL report provides a generic staff evaluation of programs for certain components and aging effects. If the applicant has identified particular components subject to AMR for its plant that are not addressed in the GALL report, or particular aging effects for a component that are not addressed in the GALL report, the staff should review the applicant's aging management programs applicable to these particular components and aging effects.
3.2.1.4 FSAR Supplement
The FSAR supplement summarizing the programs and activities for managing the effects of aging for the period of extended operation is reviewed.
3.2.2 Acceptance Criteria
The acceptance criteria for the areas of review describe methods for determining whether the applicant has met the requirements of the NRC's regulations in 10 CFR 54.21.
3.2.2.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
Acceptable methods for managing aging of the engineered safety features are described and evaluated in Chapter V of the GALL report (Ref. 2). In referencing this report, the applicant should indicate that the material presented in the GALL report is applicable to the specific plant involved, and provide the information necessary to adopt the finding of program acceptability as described and evaluated in the report. The applicant should also verify that the approvals set forth in the GALL report for generic programs apply to the applicant's programs. The applicant may reference appropriate programs as described and evaluated in the GALL report.
3.2.2.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report indicates that further evaluation should be performed for the following.
3.2.2.2.1 Cumulative Fatigue Damage
Fatigue is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The evaluation of this TLAA is addressed separately in Section 4.3 of this standard review plan.
3.2.2.2.2 Loss of Material due to General Corrosion
1. The management of loss of material due to general corrosion of pumps, valves, piping, and fittings associated with some of the BWR emergency core cooling systems [high pressure coolant injection, reactor core isolation cooling, high pressure core spray, low pressure core spray, low pressure coolant injection (residual heat removal)] and with lines to the suppression chamber and to the drywell and suppression chamber spray system should be further evaluated. The existing aging management program relies on monitoring and control of primary water chemistry based on EPRI guidelines of TR-105714 for PWRs (Ref. 3) and BWRVIP 29 (EPRI TR-103515) for BWRs (Ref. 4) to mitigate degradation. However, control of primary water chemistry does not preclude loss of material due to general corrosion at locations of stagnant flow conditions. Therefore, verification of the effectiveness of the chemistry control program should be performed to ensure that corrosion is not occurring. The GALL report recommends further evaluation of programs to manage loss of material due to general corrosion to verify the effectiveness of the chemistry control program. ). A one-time inspection of select components at susceptible locations is an acceptable method to determine whether an aging effect is not occurring or an aging effect is progressing very slowly such that the component's intended function will be maintained during the period of extended operation.
2. Loss of material due to general corrosion could occur in the containment spray (PWR) and drywell and suppression chamber spray (BWR) systems header and spray nozzle components, standby gas treatment system components (BWR), containment isolation valves and associated piping, the automatic depressurization system piping and fittings (BWR), emergency core cooling system header piping and fittings and spray nozzles (BWR), and the external surfaces of PWR and BWR carbon steel components. The GALL report recommends further evaluation on a plant specific basis to ensure that the aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.2.2.2.3 Local Loss of Material due to Pitting and Crevice Corrosion
1. The management of local loss of material due to pitting and crevice corrosion of pumps, valves, piping, and fittings associated with some of the BWR emergency core cooling system piping and fittings [high pressure coolant injection, reactor core isolation cooling, high pressure core spray, low pressure core spray, low pressure coolant injection (residual heat removal)] and with lines to the suppression chamber and to the drywell and suppression chamber spray system should be evaluated further. The existing aging management program relies on monitoring and control of primary water chemistry based on EPRI guidelines of TR-105714 for PWRs (Ref. 3) and BWRVIP 29 (EPRI TR-103515) for BWRs (Ref. 4) to mitigate degradation. However, control of coolant water chemistry does not preclude loss of material due to crevice and pitting corrosion at locations of stagnant flow conditions. Therefore, verification of the effectiveness of the chemistry control program should be performed to ensure that corrosion is not occurring. The GALL report recommends further evaluation of programs to manage the loss of material due to pitting and crevice corrosion to verify the effectiveness of the chemistry control program). A one-time inspection of select components at susceptible locations is an acceptable method to determine whether an aging effect is not occurring or an aging effect is progressing very slowly so that the component's intended function will be maintained during the period of extended operation.
2. Local loss of material from pitting and crevice corrosion could occur in the containment spray (PWR) components, containment isolation valves and associated piping, the buried portion of the refueling water tank external surface (PWRs), and automatic depressurization system piping and fittings (BWR). The GALL report recommends further evaluation to ensure that the aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RSLB-1 (Appendix A.1 of this standard review plan).
3.2.2.2.4 Local Loss of Material due to Microbiologically Influenced Corrosion
Local loss of material due to microbiologically influenced corrosion (MIC) could occur in BWR and PWR containment isolation valves and associated piping in systems that are not addressed in other chapters of the GALL report. The GALL report recommends further evaluation to ensure that the aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RSLB-1 (Appendix A.1 of this standard review plan).
3.2.2.2.5 Changes in Properties due to Elastomer Degradation
Changes in properties due to elastomer degradation could occur in seals associated with the standby gas treatment system ductwork and filters. The GALL report recommends further evaluation to ensure that the aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RSLB-1 (Appendix A.1 of this standard review plan).
3.2.2.2.6 Local Loss of Material due to Erosion
Local loss of material due to erosion could occur in the high pressure safety injection pump miniflow orifice. This aging mechanism and effect will apply only to pumps that are normally used as charging pumps in the chemical and volume control systems (PWRs). The GALL report recommends further evaluation to ensure that the aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RSLB-1 (Appendix A.1 of this standard review plan).
3.2.2.2.7 Buildup of Deposits due to Corrosion
The plugging of components due to general corrosion could occur in the spray nozzles and flow orifices of the drywell and suppression chamber spray system. This aging mechanism and effect will apply since the spray nozzles and flow orifices are occasionally wetted, even though the majority of the time this system is on standby. The wetting and drying of these components can aid in the acceleration of this particular corrosion. The GALL report recommends further evaluation to ensure that the aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RSLB-1 (Appendix A.1 of this standard review plan).
3.2.2.2.8 Quality Assurance for Aging Management of Nonsafety-Related Components
Acceptance criteria are described in Branch Technical Position IQMB-1 (Appendix A.2 of this standard review plan.)
3.2.2.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Acceptance criteria are described in Branch Technical Position RSLB-1 (Appendix A.1 of this standard review plan).
3.2.2.4 FSAR Supplement
The summary description of the programs and activities for managing the effects of aging for the period of extended operation in the FSAR supplement should be appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the bases for determining that aging effects will be managed during the period of extended operation.
3.2.3 Review Procedures
For each area of review, the following review procedures are to be followed.
3.2.3.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
The applicant may reference the GALL report in its license renewal application, as appropriate. The staff should not repeat its review of the substance of the matters described in the report. If the applicant has provided the information necessary to adopt the finding of program acceptability as described and evaluated in the GALL report, the staff should find the applicant's reference to the report in a license renewal application acceptable. In making this determination, the reviewer verifies that the applicant has provided a brief description of the system, components, materials, and environment. The reviewer also verifies that the applicant has stated that the applicable aging effects and industry and plant-specific operating experience have been reviewed by the applicant and are evaluated in the GALL report. The reviewer verifies that the applicant has identified those aging effects for the engineered safety features components that are contained in the report as applicable to its plant. In addition, the reviewer ensures that the applicant has stated that the plant programs covered by the applicant's reference contain the same program elements that the staff evaluated and relied upon in approving the corresponding generic program in the GALL report.
The reviewer should verify that the applicant has stated that certain of its aging management programs contain the same program elements as the corresponding generic program described in the GALL report, and upon which the staff relied in its evaluation. The reviewer should also verify that the applicant has stated that the GALL report is applicable to its plant with respect to these programs. The reviewer verifies that the applicant has identified the appropriate programs as described and evaluated in the GALL report. Programs evaluated in the report regarding the engineered safety features components are summarized in Table 3.2-1 of this review plan section. No further staff evaluation is necessary if so recommended in the GALL report.
3.2.3.2 Further Evaluation of Aging Management as Recommended by the GALL Report
3.2.3.2.1 Cumulative Fatigue Damage
Fatigue is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The staff reviews the evaluation of this TLAA separately, following the guidance in Section 4.3 of this standard review plan.
3.2.3.2.2 Loss of Material due to General Corrosion
1. The GALL report recommends further evaluation of programs to manage the loss of material due to general corrosion of piping and fittings associated with some of the BWR emergency core cooling systems [high pressure coolant injection, reactor core isolation cooling, high pressure core spray, low pressure core spray, low pressure coolant injection (residual heat removal)] and with lines to the suppression chamber and to the drywell and suppression chamber spray system to verify the effectiveness of the chemistry control program. A one-time inspection of select components at susceptible locations is an acceptable method to determine whether an aging effect is not occurring or an aging effect is progressing very slowly such that the component's intended function will be maintained during the period of extended operation.
The reviewer reviews the applicant's proposed program to determine whether corrosion is not occurring or the corrosion is progressing very slowly so that the component's intended function will be maintained during the period of extended operation. If an applicant proposes a one-time inspection of select components at susceptible locations to ensure that corrosion is not occurring, the reviewer verifies that the applicant's selection of susceptible locations is based on severity of conditions, time of service, and lowest design margin. The inspection techniques may include visual, ultrasonic, and surface examination techniques. Follow-up actions are to be based on the inspection results.
2. The GALL report recommends further evaluation of programs to manage the loss of material due to general corrosion of containment spray (PWR) and drywell and suppression chamber spray (BWR) systems header and spray nozzle components, standby gas treatment system components (BWR), containment isolation valves and associated piping, the automatic depressurization system piping and fittings (BWR), emergency core cooling system header piping and fittings and spray nozzles (BWR), and the external surfaces of PWR and BWR carbon steel components. The reviewer reviews the applicant's proposed programs on a case-by-case basis to ensure that an adequate program will be in place for the management of general corrosion of these components.
3.2.3.2.3 Local Loss of Material due to Pitting and Crevice Corrosion
1. The GALL report recommends further evaluation of programs to manage the loss of material due to pitting and crevice corrosion of piping and fittings associated with some of the BWR emergency core cooling system piping and fittings [high pressure coolant injection, reactor core isolation cooling, high pressure core spray, low pressure core spray, low pressure coolant injection (residual heat removal)] and with lines to the suppression chamber and to the drywell and suppression chamber spray system to verify the effectiveness of the chemistry control program. A one-time inspection of select components at susceptible locations is an acceptable method to determine whether an aging effect is not occurring or an aging effect is progressing very slowly such that the component's intended function will be maintained during the period of extended operation.
The reviewer reviews the applicant's proposed program to determine whether corrosion is not occurring or the corrosion is progressing very slowly so that the component's intended function will be maintained during the period of extended operation. If an applicant proposes a one-time inspection of select components at susceptible locations to ensure that corrosion is not occurring, the reviewer verifies that the applicant's selection of susceptible locations is based on severity of conditions, time of service, and lowest design margin. The inspection techniques may include visual, ultrasonic, and surface examination techniques. Follow-up actions are to be based on the inspection results.
2. The GALL report recommends further evaluation of programs to manage the local loss of material due to pitting and crevice corrosion of containment spray (PWR) components, containment isolation valves and associated piping, the outer buried surface of the refueling water tank (PWR), and the automatic depressurization system piping and fittings (BWR). The reviewer reviews the applicant's proposed programs on a case-by-case basis to ensure that an adequate program will be in place for the management of local loss of material due to pitting and crevice corrosion of these components.
3.2.3.2.4 Local Loss of Material due to Microbiologically Influenced Corrosion
The GALL report recommends further evaluation of programs to manage the local loss of material due to MIC of the BWR and PWR containment isolation valves and associated piping. The reviewer reviews the applicant's proposed programs on a case-by-case basis to ensure that an adequate program will be in place for the management of local loss of material due to MIC of the BWR and PWR containment isolation barriers.
3.2.3.2.5 Changes in Properties due to Elastomer Degradation
The GALL report recommends further evaluation of programs to manage changes in properties due to degradation of elastomer seals associated with BWR standby gas treatment system ductwork and filters. The reviewer reviews the applicant's proposed programs on a case-by-case basis to ensure that an adequate program will be in place to manage changes in properties due to degradation of elastomer seals in the standby gas treatment system.
3.2.3.2.6 Local loss of Material due to Erosion
The GALL report recommends further evaluation of programs to manage local loss of material due to erosion of the high pressure safety injection pump miniflow orifice. The reviewer reviews the applicant's proposed programs on a case-by-case basis to ensure that an adequate program will be in place to manage this aging effect.
3.2.3.2.7 Buildup of Deposits due to Corrosion
The GALL report recommends further evaluation of programs to manage the plugging of spray nozzles and spargers of the drywell and suppression chamber spray system. The reviewer reviews the applicant's proposed programs on a case-by-case basis to ensure that an adequate program will be in place to manage this aging effect.
3.2.3.2.8 Quality Assurance for Aging Management of Nonsafety-Related Components
The applicant's aging management programs for license renewal should contain the elements of corrective actions, the confirmation process, and administrative controls. Safety-related components are covered by 10 CFR Part 50 Appendix B, which is adequate to address these program elements. However, Appendix B does not apply to nonsafety-related components that are subject to an AMR for license renewal. Nevertheless, the applicant has the option to expand the scope of its 10 CFR Part 50 Appendix B program to include these components and address the associated program elements. If the applicant chooses this option, the reviewer verifies that the applicant has documented such a commitment in the FSAR supplement. If the applicant chooses alternative means, the branch responsible for quality assurance should be requested to review the applicant's proposal on a case-by-case basis.
3.2.3.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Review procedures are described in Branch Technical Position RSLB-1 (Appendix A.1 of this standard review plan).
3.2.3.4 FSAR Supplement
The reviewer verifies that the applicant has provided information, equivalent to that in Table 3.2-2, in the FSAR supplement for aging management of the engineered safety features for license renewal. The reviewer also verifies that the applicant has provided information, equivalent to that in Table 3.2-2, in the FSAR supplement for Subsection 3.2.3.3, "Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report."
The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Table 3.2-2, an applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
3.2.4 Evaluation Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provisions of this review plan section, and the staff's evaluation supports conclusions of the following type, to be included in the staff's safety evaluation report:
The staff concludes that the applicant has demonstrated that the aging effects associated with the engineered safety features will be adequately managed so that there is reasonable assurance that these systems will perform their intended functions in accordance with the current licensing basis during the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of the programs and activities for managing the effects of aging for the engineered safety features as reflected in the license conditions.
3.2.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specified portions of the NRC's regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
3.2.6 References
1. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants," U.S. Nuclear Regulatory Commission, July 1981.
2. NUREG-1801, "Generic Aging Lessons Learned (GALL)," U.S. Nuclear Regulatory Commission, July 2001.
3. EPRI TR-105714, PWR primary Water Chemistry Guidelines-Revision 3, Electric Power Research Institute, Palo Alto, CA, Nov. 1995.
4. EPRI TR-103515, BWR Water Chemistry Guidelines-Revision 1, Normal and Hydrogen Water Chemistry, Electric Power Research Institute, Palo Alto, CA, February 1994.
Table 3.2-1. Summary of Aging Management Programs for Engineered Safety Features Evaluated in Chapter V of the GALL Report
| Type | Component | Aging Effect/ Mechanism |
Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| BWR/PWR | Piping, fittings, and valves in emergency core cooling system | Cumulative fatigue damage | TLAA, evaluated in accordance with 10 CFR 54.21(c) | Yes, TLAA (see Subsection 3.2.2.2.1) |
| BWR | Piping, fittings, pumps, and valves in emergency core cooling system | Loss of material due to general corrosion | Water chemistry and one-time inspection |
Yes, detection of aging effects
is to be further evaluated (see Subsection 3.2.2.2.2.1) |
| BWR/PWR | Components in containment spray (PWR only), standby gas treatment (BWR only), containment isolation, and emergency core cooling systems | Loss of material due to general corrosion | Plant specific | Yes, plant specific (see Subsection 3.2.2.2.2.2) |
| BWR | Piping, fittings, pumps, and valves in emergency core cooling system | Loss of material due to pitting and crevice corrosion | Water chemistry and one-time inspection | Yes, detection of aging effects
is to be further evaluated (see Subsection 3.2.2.2.3.1) |
| BWR/PWR | Components in containment spray (PWR only), standby gas treatment (BWR only), containment isolation, and emergency core cooling systems | Loss of material due to pitting
and to
Loss of material due to pitting and crevice corrosion |
Plant specific | Yes, plant specific (see Subsection 3.2.2.2.3.2) |
| BWR/PWR | Containment isolation valves and associated piping | Loss of material due to microbiologically influenced corrosion | Plant specific | Yes, plant specific (see Subsection 3.2.2.2.4) |
| BWR | Seals in standby gas treatment system | Changes in properties due to elastomer degradation | Plant specific | Yes, plant specific (see Subsection 3.2.2.2.5) |
| PWR | High pressure safety injection (charging) pump miniflow orifice | Loss of material due to erosion | Plant specific | Yes, plant specific (see Subsection 3.2.2.2.6) |
Table 3.2-1. Summary of Aging Management Programs for Engineered Safety Features Evaluated in Chapter V of the GALL Report (continued)
| Type | Component | Aging Effect/ Mechanism |
Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| BWR | Drywell and suppression chamber spray system nozzles and flow orifices | Plugging of nozzles and flow orifices due to general corrosion | Plant specific | Yes, plant specific (see Subsection 3.2.2.2.7) |
| BWR/PWR | Piping and fittings of CASS in emergency core cooling system | Loss of fracture toughness due to thermal aging embrittlement | Thermal aging embrittlement of CASS | No |
| BWR/PWR | Components serviced by open-cycle cooling system | Local loss of material due to corrosion and/or buildup of deposit due to biofouling | Open-cycle cooling water system | No |
| BWR/PWR | Components serviced by closed-cycle cooling system | Loss of material due to general, pitting, and crevice corrosion | Closed-cycle cooling water system | No |
| BWR | Emergency core cooling system valves and lines to and from HPCI and RCIC pump turbines | Wall thinning due to flow-accelerated corrosion | Flow-accelerated corrosion | No |
| PWR | Pumps, valves, piping, and fittings in containment spray and emergency core cooling systems | Crack initiation and growth due to SCC | Water chemistry | No |
| BWR | Pumps, valves, piping, and fittings in emergency core cooling systems | Crack initiation and growth due to SCC and IGSCC | Water chemistry and BWR stress corrosion cracking | No |
| PWR | Carbon steel components | Loss of material due to boric acid corrosion | Boric acid corrosion | No |
| BWR/PWR | Closure bolting in high pressure or high temperature systems | Loss of material due to general corrosion, loss of preload due to stress relaxation, and crack initiation and growth due to cyclic loading or SCC | Bolting integrity | No |
Table 3.2-2. FSAR Supplement for Aging Management of Engineered Safety Features
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Bolting integrity (BWR/PWR) |
This program includes periodic inspection of closure bolting for Indication of potential problems including loss of reload, cracking, and loss of material. This program consists of guidelines on materials selection, strength and hardness properties, installation procedures, lubricants and sealants, corrosion considerations in the selection and installation of pressure-retaining bolting for nuclear applications, and enhanced inspection techniques. This program relies on the bolting integrity program delineated in NUREG-1339 and industry's recommendations delineated in EPRI NP-5769, with the exceptions noted in NUREG-1339 for safety-related bolting, and EPRI TR-104213 for pressure retaining bolting and structural bolting. | Existing program |
| Boric acid corrosion (PWR) |
The program consists of (1) visual inspection of external surfaces that are potentially exposed to borated water leakage, (2) timely discovery of leak path and removal of the boric acid residues, (3) assessment of the damage, and (4) follow up inspection for adequacy. This program is implemented in response to GL 88-05. | Existing program |
| Closed-cycle cooling water system (BWR/PWR) | The program relies on preventive measures to minimize corrosion by maintaining inhibitors and by performing non-chemistry monitoring consisting of inspection and nondestructive evaluations based on the guidelines of EPRI-TR-107396 for closed-cycle cooling water systems. | Existing program |
| Flow-accelerated corrosion (FAC) (BWR/PWR) | The program consists of (1) conduct appropriate analysis and baseline inspection, (2) determine extent of thinning, and replace/repair components, and (3) perform follow-up inspections to confirm or quantify and take longer-term corrective actions. The program relies on implementation of EPRI guidelines of NSAC-202L-R2. | Existing program |
| One-time inspection | To verify the effectiveness of the water chemistry control program by determining if the aging effect is not occurring or the aging effect is progressing so slowly that the intended function will be maintained during the period of extended operation, a one-time inspection of pumps, valves, piping, and fittings associated with certain BWR emergency core cooling systems [high pressure coolant injection, reactor core isolation cooling, high pressure core spray, low pressure core spray, low pressure coolant injection (residual heat removal)]; and with pipe lines in a BWR plant to the suppression chamber and to the drywell and suppression chamber spray system is performed. | The inspection should be completed before the period of extended operation |
Table 3.2-2. FSAR Supplement for Aging Management of Engineered Safety Features (continued)
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Open-cycle cooling water system (BWR/PWR) | The program includes (a) surveillance and control of biofouling, (b) tests to verify heat transfer, (c) routine inspection and maintenance program, (d) system walk down inspection, and (e) review of maintenance, operating, and training practices and procedures. The program provides assurance that the open-cycle cooling water system is in compliance with General Design Criteria and Quality Assurance to ensure that the open-cycle cooling water (or service water) system can be managed for an extended period of operation. This program is in response to NRC GL 89-13. | Existing program |
| Plant-specific AMP | The description should contain information associated with the basis for determining that aging effects will be managed during the period of extended operation. | Program should be implemented before the period of extended operation |
| Quality assurance | The 10 CFR Part 50 Appendix B program provides for corrective actions, the confirmation process, and administrative controls for aging management programs for license renewal. The scope of this existing program will be expanded to include nonsafety-related structures and components that are subject to an AMR for license renewal. | Program should be implemented before the period of extended operation |
| Thermal aging
embrittlement of
CASS AMP (BWR/PWR) |
The program consists of the determination of the susceptibility of CASS piping and fittings in PWR ECCS systems including interfacing pipe lines to the chemical and volume control system and to the spent fuel pool; and in BWR ECCS systems including interfacing pipe lines to the suppression chamber and to the drywell and suppression chamber spray system in regard to thermal aging embrittlement based on the casting method, Mo content, and ferrite percentage. For potentially susceptible piping, aging management is accomplished either through enhanced volumetric examination or component-specific flaw tolerance evaluation. | Existing program |
| Water chemistry (BWR/PWR) |
To mitigate aging effects on component surfaces that are exposed to water as a process fluid, chemistry programs are used to control water impurities (e.g., chloride, fluoride, sulfate) that accelerate corrosion. This program relies on monitoring and control of water chemistry to keep peak levels of various contaminants below the system-specific limits based on EPRI guidelines of TR-103515 for water chemistry in BWRs, and TR-105714 for primary water chemistry in PWRs. | Existing program |
| BWR Stress Corrosion Cracking | The program to manage intergranular stress corrosion cracking (IGSCC) in boiling water reactor (BWR) coolant pressure boundary piping made of stainless steel (SS) is delineated, in part, in NUREG-0313, Rev. 2, and Nuclear Regulatory Commission (NRC) Generic Letter (GL) 88-01 and its Supplement 1. The program includes (a) preventive measures to mitigate IGSCC and (b) inspections to monitor IGSCC and its effects | Existing Program |
| * An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date. | ||
3.3 Aging Management of Auxiliary Systems
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Review Responsibilities
Primary - Branch responsible for materials and chemical engineering
Secondary - Branch responsible for mechanical engineering
3.3.1 Areas of Review
This review plan section addresses the aging management review (AMR) of the auxiliary systems for license renewal. For a recent vintage plant, the information related to the auxiliary systems is contained in Chapter 9, "Auxiliary Systems," of the plant's FSAR consistent with the "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants" (NUREG-0800) (Ref. 1). The auxiliary systems contained in this review plan section are generally consistent with those contained in NUREG-0800 except for refueling water, chilled water, heat removal, condenser circulating water, and condensate storage system. For older plants, the location of applicable information is plant-specific because their FSAR may have predated NUREG-0800. Typical auxiliary systems that are subject to an AMR for license renewal are new fuel storage, spent fuel storage, spent fuel pool cooling and cleanup (BWR/PWR), suppression pool cleanup (BWR), overhead heavy load and light load (related to refueling) handling, open-cycle cooling water, closed-cycle cooling water, ultimate heat sink, compressed air, chemical and volume control (PWR), standby liquid control (BWR), reactor water cleanup (BWR), shutdown cooling (older BWR), control room area ventilation, auxiliary and radwaste area ventilation, primary containment heating and ventilation, diesel generator building ventilation, fire protection, diesel fuel oil, and emergency diesel generator.
Aging management is reviewed, following the guidance in Section 3.1, for portions of the chemical and volume control system for PWRs, and for standby liquid control, reactor water cleanup, and shutdown cooling systems extending up to the first isolation valve outside of containment for BWRs (the shutdown cooling systems for older BWRs). The following systems have portions that are classified as Group B quality standard: open-cycle cooling water (service water system), closed-cycle cooling water, compressed air, standby liquid control, shutdown cooling system (older BWR), control room area ventilation and auxiliary and radwaste area ventilation. Aging management for these portions is reviewed following the guidance in Section 3.3. The aging management program for the cooling towers is reviewed following the guidance in Section 3.5 for "Group 6" structures.
The staff has issued a GALL report addressing aging management for license renewal (Ref. 2). The GALL report documents the staff's basis for determining whether generic existing programs are adequate to manage aging without change, or generic existing programs should be augmented for license renewal. The GALL report may be referenced in a license renewal application, and should be treated in the same manner as an approved topical report.
Because a license renewal applicant may or may not be able to reference the GALL report as explained below, the following areas are reviewed:
3.3.1.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
An applicant may reference the GALL report in a license renewal application to demonstrate that the applicant's programs at its facility correspond to those reviewed and approved in the report, and that no further staff review is required. If the material presented in the GALL report is applicable to the applicant's facility, the staff should find the applicant's reference to the report acceptable. In making this determination, the staff should consider whether the applicant has identified specific programs described and evaluated in the GALL report. The staff, however, should not repeat its review of the substance of the matters described in the report. Rather, the staff should ensure that the applicant verifies that the approvals set forth in the GALL report for generic programs apply to the applicant's programs.
3.3.1.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report provides the basis for identifying those programs that warrant further evaluation during the staff review of a license renewal application. The staff review focus should be on augmented programs for license renewal.
3.3.1.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
The GALL report provides a generic staff evaluation of certain aging management programs. If an applicant does not rely on a particular program for license renewal, or if the applicant indicates that the generic staff evaluation of the elements of a particular program does not apply to its plant, the staff should review each such aging management program to which the GALL report does not apply. The GALL report provides a generic staff evaluation of programs for certain components and aging effects. If the applicant has identified particular components subject to an AMR for its plant that are not addressed in the GALL report, or particular aging effects for a component that are not addressed in the GALL report, the staff should review the applicant's aging management programs applicable to these particular components and aging effects.
3.3.1.4 FSAR Supplement
The FSAR supplement summarizing the programs and activities for managing the effects of aging for the period of extended operation is reviewed.
3.3.2 Acceptance Criteria
The acceptance criteria for the areas of review describe methods for determining whether the applicant has met the requirements of the NRC's regulations in 10 CFR 54.21.
3.3.2.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
Acceptable methods for managing aging of the auxiliary systems are described and evaluated in Chapter VII of the GALL report (Ref. 2). In referencing this report, an applicant should indicate that the material presented in the GALL report is applicable to the specific plant involved, and provide the information necessary to adopt the finding of program acceptability as described and evaluated in the report. An applicant should also verify that the approvals set forth in the GALL report for generic programs apply to the applicant's programs. An applicant may reference appropriate programs as described and evaluated in the GALL report.
3.3.2.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report indicates that further evaluation should be performed for:
3.3.2.2.1 Loss of Material due to General, Pitting, and Crevice Corrosion
1. Loss of material due to general, pitting, and crevice corrosion could occur in the channel head and access cover, tubes, and tubesheets of the heat exchanger in the spent fuel pool cooling and cleanup. The water chemistry program relies on monitoring and control of reactor water chemistry based on EPRI guidelines of BWRVIP-29 (TR-103515) (Ref. 3) for water chemistry in BWRs, TR-105714 (Ref. 4) for primary water chemistry in PWRs, and TR-102134 (Ref. 5) for secondary water chemistry in PWRs to manage the effects of loss of material from general, pitting or crevice corrosion. However, high concentrations of impurities at crevices and locations of stagnant flow conditions could cause general, pitting, or crevice corrosion. Therefore, verification of the effectiveness of the chemistry control program should be performed to ensure that corrosion is not occurring. The GALL report recommends further evaluation of programs to manage loss of material from general, pitting, and crevice corrosion to verify the effectiveness of the water chemistry program. A one-time inspection of select components at susceptible locations is an acceptable method to ensure that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation.
2. Loss of material due to pitting and crevice corrosion could occur in the filter housing, valve bodies, and nozzles of the ion exchanger in the spent fuel pool cooling and cleanup system (PWR), in the piping, filter housing, valve bodies, and shell and nozzles of the ion exchanger in the spent fuel pool cooling and cleanup system (BWR), and in the piping and pump casing in the shutdown cooling system (older BWR). The water chemistry program relies on monitoring and control of reactor water chemistry based on EPRI guidelines of BWRVIP-29 (TR-103515) (Ref. 3) for water chemistry in BWRs, TR-105714 (Ref. 4) for primary water chemistry in PWRs, and TR-102134 (Ref. 5) for secondary water chemistry in PWRs to manage the effects of loss of material from pitting or crevice corrosion. However, high concentrations of impurities at crevices and locations of stagnant flow conditions could cause pitting, or crevice corrosion. Therefore, verification of the effectiveness of the chemistry control program should be performed to ensure that corrosion is not occurring. The GALL report recommends further evaluation of programs to manage loss of material from pitting and crevice corrosion to verify the effectiveness of the water chemistry program. A one-time inspection of select components at susceptible locations is an acceptable method to ensure that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation.
3.3.2.2.2 Hardening and Cracking or Loss of Strength due to Elastomer Degradation or Loss of Material due to Wear
Hardening and cracking due to elastomer degradation could occur in elastomer linings of the filter, valve, and ion exchangers in spent fuel pool cooling and cleanup systems (BWR and PWR). Hardening and loss of strength due to elastomer degradation could occur in the collars and seals of the duct and in the elastomer seals of the filters in the control room area, auxiliary and radwaste area, and primary containment heating ventilation systems and in the collars and seals of the duct in the diesel generator building ventilation system. Loss of material due to wear could occur in the collars and seals of the duct in the ventilation systems. The GALL report recommends further evaluation to ensure that these aging effects are adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
3.3.2.2.3 Cumulative Fatigue Damage
Fatigue is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The evaluation of this TLAA is addressed separately in Section 4.3 of this standard review plan.
3.3.2.2.4 Crack Initiation and Growth due to Cracking or Stress Corrosion Cracking
Crack initiation and growth due to SCC could occur in the regenerative and non-regenerative heat exchanger components in the reactor water cleanup system (BWR) and due to cracking in the high-pressure pump in the chemical and volume control system (PWR). The GALL report recommends further evaluation to ensure that these aging effects are managed adequately. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
3.3.2.2.5 Loss of Material due to General, Microbiologically Influenced, Pitting, and Crevice Corrosion
Loss of material due to general, pitting, and crevice corrosion could occur in the piping and filter housing and supports in the control room area, the auxiliary and radwaste area, the primary containment heating and ventilation systems, in the piping of the diesel generator building ventilation system, in the aboveground piping and fittings, valves, and pumps in the diesel fuel oil system and in the diesel engine starting air, combustion air intake, and combustion air exhaust subsystems in the emergency diesel generator system. Loss of material due to general, pitting, crevice, and microbiologically influenced corrosion (MIC) could occur in the duct fittings, access doors, and closure bolts, equipment frames and housing of the duct, due to pitting and crevice corrosion could occur in the heating/cooling coils of the air handler heating/cooling, and due to general corrosion could occur on the external surfaces of all carbon steel structures and components, including bolting exposed to operating temperatures less than 212°F in the ventilation systems. The GALL report recommends further evaluation to ensure that these aging effects are adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
3.3.2.2.6 Loss of Material due to General, Galvanic, Pitting, and Crevice Corrosion
Loss of material due to general, galvanic, pitting, and crevice corrosion could occur in tanks, piping, valve bodies, and tubing in the reactor coolant pump oil collection system in fire protection. The fire protection program relies on a combination of visual and volumetric examinations in accordance with the guidelines of 10 CFR Part 50 Appendix R and Branch Technical Position 9.5-1 to manage loss of material from corrosion. However, corrosion may occur at locations where water from wash downs may accumulate. Therefore, verification of the effectiveness of the program should be performed to ensure that corrosion is not occurring. The GALL report recommends further evaluation of programs to manage loss of material due to general, galvanic, pitting, and crevice corrosion to verify the effectiveness of the program. A one-time inspection of the bottom half of the interior surface of the tank of the reactor coolant pump oil collection system is an acceptable method to ensure that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation.
3.3.2.2.7 Loss of Material due to General, Pitting, Crevice, and Microbiologically Influenced Corrosion and Biofouling
Loss of material due to general, pitting, and crevice corrosion, MIC, and biofouling could occur in the internal surface of tanks in the diesel fuel oil system and due to general, pitting, and crevice corrosion and MIC in the tanks of the diesel fuel oil system in the emergency diesel generator system. The existing aging management program relies on the fuel oil chemistry program for monitoring and control of fuel oil contamination in accordance with the guidelines of ASTM Standards D4057, D1796, D2709 and D2276 to manage loss of material due to corrosion or biofouling. Corrosion or biofouling may occur at locations where contaminants accumulate. Verification of the effectiveness of the chemistry control program should be performed to ensure that corrosion is not occurring. The GALL report recommends further evaluation of programs to manage corrosion/biofouling to verify the effectiveness of the program. A one-time inspection of selected components at susceptible locations is an acceptable method to ensure that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation.
3.3.2.2.8 Quality Assurance for Aging Management of Nonsafety-Related Components
Acceptance criteria are described in Branch Technical Position IQMB-1 (Appendix A.2, of this standard review plan.)
3.3.2.2.9 Crack Initiation and Growth due to Stress Corrosion Cracking and Cyclic Loading
Crack initiation and growth due to SCC and cyclic loading could occur in the channel head and access cover, tubesheet, tubes, shell and access cover, and closure bolting of the regenerative heat exchanger and in the channel head and access cover, tubesheet, and tubes of the letdown heat exchanger in the chemical and volume control system (PWR). The water chemistry program relies on monitoring and control of water chemistry based on the guidelines of TR-105714 (Ref. 4) for primary water chemistry in PWRs to manage the effects of crack initiation and growth due to SCC and cyclic loading. Verification of the effectiveness of the chemistry control program should be performed to ensure that crack initiation and growth are not occurring. The GALL report recommends further evaluation to manage crack initiation and growth from SCC and cyclic loading for these systems to verify the effectiveness of the water chemistry program. A one-time inspection of select components and susceptible locations is an acceptable method to ensure that crack initiation and growth are not occurring and that the components' intended function will be maintained during extended operations.
3.3.2.2.10 Reduction of Neutron-Absorbing Capacity and Loss of Material due to General Corrosion
Reduction of neutron-absorbing capacity and loss of material due to general corrosion could occur in the neutron-absorbing sheets of the spent fuel storage rack in the spent fuel storage. The GALL report recommends further evaluation to ensure that these aging effects are adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
3.3.2.2.11 Loss of Material due to General, Pitting, Crevice, and Microbiologically Influenced Corrosion
Loss of material due to general, pitting, and crevice corrosion and MIC could occur in the underground piping and fittings in the open-cycle cooling water system (service water system) and in the diesel fuel oil system. The buried piping and tanks inspection program relies on industry practice, frequency of pipe excavation, and operating experience to manage the effects of loss of material from general, pitting, and crevice corrosion and MIC. The effectiveness of the buried piping and tanks inspection program should be verified to evaluate an applicant's inspection frequency and operating experience with buried components, ensuring that loss of material is not occurring.
3.3.2.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
3.3.2.4 FSAR Supplement
The summary description of the programs and activities for managing the effects of aging for the period of extended operation in the FSAR supplement should be appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the bases for determining that aging effects will be managed during the period of extended operation.
3.3.3 Review Procedures
For each area of review, the following review procedures are to be followed:
3.3.3.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
The applicant may reference the GALL report in its license renewal application, as appropriate. The staff should not repeat its review of the substance of the matters described in the report. If the applicant has provided the information necessary to adopt the finding of program acceptability as described and evaluated in the GALL report, the staff should find the applicant's reference to the report in a license renewal application acceptable. In making this determination, the reviewer verifies that the applicant has provided a brief description of the system, components, materials, and environment. The reviewer also verifies that the applicant has stated that the applicable aging effects and industry and plant-specific operating experience have been reviewed by the applicant and are evaluated in the GALL report. The reviewer verifies that the applicant has identified those aging effects for the auxiliary system components that are contained in the report as applicable to its plant. In addition, the reviewer verifies that the applicant has stated that the plant programs covered by the applicant's reference contain the same program elements that the staff evaluated and relied upon in approving the corresponding generic program in the GALL report.
The reviewer should verify that the applicant has stated that certain of its aging management programs contain the same program elements as the corresponding generic program described in the GALL report, and upon which the staff relied in its evaluation. The reviewer should also verify that the applicant has state that the GALL report is applicable to its plant with respect to these programs. The reviewer verifies that the applicant has identified the appropriate programs as described and evaluated in the GALL report. Programs evaluated in the report regarding the auxiliary system components are summarized in Table 3.3-1 of this review plan section. No further staff evaluation is necessary if so recommended in the GALL report.
3.3.3.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report indicates that further evaluation should be performed for:
3.3.3.2.1 Loss of Material due to General, Pitting, and Crevice Corrosion
1. The GALL report recommends further evaluation of programs to manage loss of material due to general, pitting, and crevice corrosion of the channel head and access cover, tubes, and tubesheets of the heat exchanger in the spent fuel pool cooling and cleanup to verify the effectiveness of the water chemistry program. The water chemistry program relies on monitoring and control of reactor water chemistry based on EPRI guidelines of BWRVIP-29 (TR-103515) for water chemistry in BWRs, TR-105714 for primary water chemistry in PWRs, and TR-102134 for secondary water chemistry in PWRs to manage the effects of loss of material from general, pitting or crevice corrosion (Ref. 3-5). However, high concentrations of impurities at crevices and locations of stagnant flow conditions could cause general, pitting or crevice corrosion. Therefore, verification of the effectiveness of the water chemistry control program should be performed to ensure that corrosion is not occurring and that the component's intended function would be maintained during the period of extended operation.
The reviewer reviews the applicant's proposed program to ensure that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation. If the applicant proposes a one-time inspection of select components at susceptible locations to ensure that corrosion is not occurring, the reviewer verifies that the applicant's selection of susceptible locations is based on severity of conditions, time of service, and lowest design margin. The reviewer also verifies that the proposed inspection would be performed using techniques similar to ASME Code and ASTM standards, including visual, ultrasonic, and surface techniques (Ref. 6, 7).
2. The GALL report recommends further evaluation of programs to manage loss of material due to pitting and crevice corrosion of the filter housing, valve bodies, and nozzles of the ion exchanger in the spent fuel pool cooling and cleanup system (PWR), of the piping, filter housing, valve bodies, and shell and nozzles of the ion exchanger in the spent fuel pool cooling and cleanup system (BWR) and of the piping and pump casing in the shutdown cooling system (older BWR) to verify the effectiveness of the water chemistry program. The water chemistry program relies on monitoring and control of reactor water chemistry based on EPRI guidelines of BWRVIP-29 (TR-103515) for water chemistry in BWRs, TR-105714 for primary water chemistry in PWRs, and TR-102134 for secondary water chemistry in PWRs to manage the effects of loss of material from pitting or crevice corrosion (Ref. 3-5). However, high concentrations of impurities at crevices and locations of stagnant flow conditions could cause pitting or crevice corrosion. Therefore, verification of the effectiveness of the water chemistry control program should be performed to ensure that corrosion is not occurring and that the component's intended function would be maintained during the period of extended operation.
The reviewer reviews the applicant's proposed program to ensure that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation. If the applicant proposes a one-time inspection of select components at susceptible locations to ensure that corrosion is not occurring, the reviewer verifies that the applicant's selection of susceptible locations is based on severity of conditions, time of service, and lowest design margin. The reviewer also verifies that the proposed inspection would be performed using techniques similar to ASME Code and ASTM standards, including visual, ultrasonic, and surface techniques (Ref. 6, 7).
3.3.3.2.2 Hardening and Cracking or Loss of Strength due to Elastomer Degradation or Loss of Material due to Wear
The GALL report recommends further evaluation of programs to manage the hardening and cracking due to elastomer degradation of valves in spent fuel pool cooling and cleanup system (BWR and PWR). The GALL report also recommends further evaluation of programs to manage the hardening and loss of strength due to elastomer degradation of the collars and seals of the duct and of the elastomer seals of the filters in the control room area, auxiliary and radwaste area, and primary containment heating and ventilation systems and of the collars and seals of the duct in the diesel generator building ventilation system. The GALL report also recommends further evaluation of programs to manage the loss of material due to wear of the collars and seals of the duct in the ventilation systems. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3.3.3.2.3 Cumulative Fatigue Damage
Fatigue is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The evaluation of this TLAA is addressed separately in Section 4.3 of this standard review plan.
3.3.3.2.4 Crack Initiation and Growth due to Cracking or Stress Corrosion Cracking
The GALL report recommends further evaluation of programs to manage the crack initiation and growth due to SCC of the regenerative and non-regenerative heat exchanger components in the reactor water cleanup system (BWR) and due to cracking of the high-pressure pump in the chemical and volume control system (PWR). The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3.3.3.2.5 Loss of Material due to General, Microbiologically Influenced, Pitting, and Crevice Corrosion
The GALL report recommends further evaluation of programs to manage the loss of material due to general, pitting, and crevice corrosion of the piping and filter housing and supports in the control room area, the auxiliary and radwaste area, and the primary containment heating and ventilation systems, of the piping of the diesel generator building ventilation system, and of the aboveground piping and fittings, valves, and pumps in the diesel fuel oil system and of the diesel engine starting air, combustion air intake, and combustion air exhaust subsystems in the emergency diesel generator system. The GALL report also recommends further evaluation of programs to manage the loss of material due to general, pitting, and crevice corrosion and MIC of the duct fittings, access doors, and closure bolts, equipment frames and housing of the duct, due to pitting and crevice corrosion of the heating/cooling coils of the air handler heating/cooling, and due to general corrosion of the external surfaces of all carbon steel structures and components, including bolting exposed to operating temperatures less than 212°F in the ventilation systems. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3.3.3.2.6 Loss of Material due to General, Galvanic, Pitting, and Crevice Corrosion
The GALL report recommends further evaluation of programs to manage the loss of material due to general, galvanic, pitting, and crevice corrosion of tanks, piping, valve bodies, and tubing in the reactor coolant pump oil collection system in fire protection. The fire protection program relies on a combination of visual and volumetric examinations in accordance with the guidelines of 10 CFR Part 50 Appendix R and Branch Technical Position 9.5-1 to manage loss of material from corrosion. However, corrosion may occur at locations where water from wash downs may accumulate. Therefore, verification of the effectiveness of the program should be performed to ensure that degradation is not occurring and that the component's intended function will be maintained during the period of extended operation.
The reviewer reviews the applicant's proposed program to ensure that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation. If the applicant proposes a one-time visual inspection of the bottom half of the interior of the tank, the inspection would be performed to ensure that corrosion is not occurring. If corrosion is identified, a volumetric examination would then be conducted on any problematic areas. The results of examinations will be used as a leading indicator of other susceptible components. The reviewer also verifies that the proposed inspection would be performed using techniques similar to ASME Code and ASTM standards, including visual, ultrasonic, and surface examination techniques (Ref. 6, 7).
3.3.3.2.7 Loss of Material due to General, Pitting, Crevice, and Microbiologically Influenced Corrosion and Biofouling
The Gall report recommends further evaluation of programs to manage loss of material due to general, pitting, and crevice corrosion and MIC and to biofouling of the internal surface of tanks in the diesel fuel oil system and due to general, pitting, crevice, and MIC of the tanks of the diesel engine fuel oil system in the emergency diesel generator system. The fuel oil chemistry program relies on monitoring and control of fuel oil contamination in accordance with the guidelines of ASTM Standards D4057, D1796, D2709 and D2276 to manage loss of material due to corrosion or biofouling. Corrosion or biofouling may occur at locations where contaminants accumulate. Verification of the effectiveness of the fuel oil program should be performed to ensure that corrosion/biofouling is not occurring and that the component's intended function will be maintained during the period of extended operation.
The reviewer reviews the applicant's proposed program to ensure that corrosion/biofouling is not occurring and that the component's intended function will be maintained during the period of extended operation. If an applicant proposes a one-time inspection of select components and susceptible locations to ensure that corrosion/biofouling is not occurring, the reviewer verifies that the applicant's selection of susceptible locations is based on severity of conditions, time of service, and lowest design margin. The reviewer also verifies that the proposed inspection would be performed using techniques similar to ASME Code and ASTM standards, including visual, ultrasonic, and surface techniques (Ref. 6, 7).
3.3.3.2.8 Quality Assurance for Aging Management of Nonsafety-Related Components
The applicant's aging management programs for license renewal should contain the elements of corrective actions, the confirmation process, and administrative controls. Safety-related components are covered by 10 CFR Part 50 Appendix B, which is adequate to address these program elements. However, Appendix B does not apply to nonsafety-related components that are subject to an AMR for license renewal. Nevertheless, the applicant has the option to expand the scope of its 10 CFR Part 50 Appendix B program to include these components and address the associated program elements. If the applicant chooses this option, the reviewer verifies that the applicant has documented such a commitment in the FSAR supplement. If the applicant chooses alternative means, the branch responsible for quality assurance should be requested to review the applicant's proposal on a case-by-case basis.
3.3.3.2.9 Crack Initiation and Growth due to Stress Corrosion Cracking and Cyclic Loading
The GALL report recommends further evaluation of programs to manage the crack initiation and growth due to SCC and cyclic loading of the channel head and access cover, tubesheet, tubes, shell and access cover, and closure bolting of the regenerative heat exchanger and in the channel head and access over, tubesheet, and tubes of the letdown heat exchanger in the chemical and volume control system (PWR) to verify the effectiveness of the water chemistry program. The water chemistry program relies on monitoring and control of reactor water chemistry based on TR-105714 for primary water chemistry in PWRs to manage the effects of crack initiation and growth from SCC and cyclic loading (Ref. 4). The effectiveness of the water chemistry control program should be performed to verified that cracking is not occurring and that the component's intended function would be maintained during the period of extended operation.
The reviewer reviews the applicant's proposed program to ensure that cracking is not occurring and that the component's intended function will be maintained during extended operation. If the applicant proposes a one-time inspection of select components at susceptible locations to ensure that corrosion is not occurring, the reviewer verifies that the applicant's selection of susceptible locations is based on severity of conditions, time of service, and lowest design margin. The reviewer also verifies that the proposed inspection would be performed by using techniques similar to ASME Code and ASTM standards, including visual, ultrasonic, and surface techniques (Ref. 6, 7).
3.3.3.2.10 Reduction of Neutron-Absorbing Capacity and Loss of Material due to General Corrosion
The GALL report recommends further evaluation of programs to manage reduction of neutron-absorbing capacity and loss of material due to general corrosion of the neutron-absorbing sheets of the spent fuel storage rack in the spent fuel storage. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3.3.3.2.11 Loss of Material due to General, Pitting, Crevice, and Microbiologically Influenced Corrosion
The GALL report recommends further evaluation of programs to manage loss of material due to general, pitting, and crevice corrosion and MIC of the underground piping and fittings in the open-cycle cooling water system (service water system) and in the diesel fuel oil system to verify the effectiveness of the buried piping and tanks inspection program. The buried piping and tanks inspection program relies on industry practice, frequency of pipe excavation, and operating experience to manage the effects of loss of material from general, pitting, and crevice corrosion and MIC. The effectiveness of the buried piping and tanks inspection program should be verified to evaluate an applicant's inspection frequency and operating experience with buried components, ensuring that corrosion is not occurring and that the component's intended function will be maintained during extended operation.
3.3.3.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Review procedures are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan.)
3.3.3.4 FSAR Supplement
The reviewer verifies that the applicant has provided information, equivalent to that in Table 3.3-2, in the FSAR supplement for aging management of the auxiliary systems for license renewal. The reviewer also verifies that the applicant has provided information, equivalent to that in Table 3.3-2, in the FSAR supplement for Subsection 3.3.3.3, "Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report."
The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Table 3.3-2, an applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
3.3.4 Evaluation Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provisions of this review plan section and that the staff's evaluation supports conclusions of the following type, to be included in the staff's safety evaluation report:
The staff concludes that the applicant has demonstrated that the aging effects associated with the auxiliary systems will be adequately managed so that there is reasonable assurance that these systems will perform their intended functions in accordance with the current licensing basis during the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of the programs and activities for managing the effects of aging for the auxiliary systems as reflected in the license conditions.
3.3.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specified portions of the NRC's regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
3.3.6 References
1. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants," U.S. Nuclear Regulatory Commission, July 1981.
2. NUREG-1801, "Generic Aging Lessons Learned (GALL)," U.S. Nuclear Regulatory Commission, July 2001.
3. BWRVIP-29 (EPRI TR-103515), BWR Water Chemistry Guidelines-Revision 3, Normal and Hydrogen Water Chemistry, Electric Power Research Institute, Palo Alto, CA, February 1994.
4. EPRI TR-105714, PWR Primary Water Chemistry Guidelines-Revision 3, Electric Power Research Institute, Palo Alto, CA, Nov. 1995.
5. EPRI TR-102134, PWR Secondary Water Chemistry Guideline-Revision 3, Electric Power Research Institute, Palo Alto, CA, May 1993.
6. ASME Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, The ASME Boiler and Pressure Vessel Code, 1989 or later edition as approved in 10 CFR 50.55a, The American Society of Mechanical Engineers, New York, NY.
7. ASTM D95-83, Standard Test Method for Water in Petroleum Products and Bituminous Materials by Distillation, American Society for Testing and Materials, West Conshohocken, PA, 1983.
Table 3.3-1. Summary of Aging Management Programs for Auxiliary Systems Evaluated in Chapter VII of the GALL Report
| Type | Component |
Aging Effect/ Mechanism |
Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| BWR/PWR | Components in spent fuel pool cooling and cleanup | Loss of material due to general, pitting, and crevice corrosion | Water chemistry and one-time inspection | Yes, detection of aging effects is to be further evaluated (see subsections 3.3.2.2.1.1 and 3.3.2.2.1.2) |
| BWR/PWR | Linings in spent fuel pool cooling and cleanup system; seals and collars in ventilation systems | Hardening, cracking and loss of
strength due to elastomer
degradation;
loss of material due to wear |
Plant specific | Yes, plant specific (see
subsection 3.3.2.2.2)
|
| BWR/PWR | Components in load handling, chemical and volume control system (PWR), and reactor water cleanup and shutdown cooling systems (older BWR) | Cumulative fatigue damage | TLAA, evaluated in accordance with 10 CFR 54.21(c) | Yes, TLAA (see subsection 3.3.2.2.3) |
| BWR/
PWR |
Heat exchangers in reactor water cleanup system (BWR); high pressure pumps in chemical and volume control system (PWR) | Crack initiation and growth due to SCC or cracking | Plant specific | Yes, plant specific (see subsection 3.3.2.2.4) |
| BWR/PWR | Components in ventilation systems, diesel fuel oil system, and emergency diesel generator systems; external surfaces of carbon steel components | Loss of material due to general, pitting, and crevice corrosion, and MIC | Plant specific | Yes, plant specific
(see subsection 3.3.2.2.5) |
| BWR/PWR | Components in reactor coolant pump oil collect system of fire protection | Loss of material due to galvanic, general, pitting, and crevice corrosion | One-time inspection | Yes, detection of aging effects is to be further evaluated (see subsection 3.3.2.2.6) |
| BWR/PWR | Diesel fuel oil tanks in diesel fuel oil system and emergency diesel generator system | Loss of material due to general, pitting, and crevice corrosion, MIC, and biofouling | Fuel oil chemistry and one-time inspection | Yes, detection of aging effects is to be further evaluated (see subsection 3.3.2.2.7) |
Table 3.3-1. Summary of Aging Management Programs for Auxiliary Systems Evaluated in Chapter VII of the GALL Report (continued)
| Type | Component | Aging Effect/ Mechanism |
Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| BWR | Piping, pump casing, and valve body and bonnets in shutdown cooling system (older BWR) | Loss of material due to pitting and crevice corrosion | Water chemistry and one-time inspection | Yes, detection of aging effects is to be further evaluated (see subsection 3.3.2.2.1.2) |
| PWR | Heat exchangers in chemical and volume control system | Crack initiation and growth due to SCC and cyclic loading | Water chemistry and a plant-specific verification program | Yes, plant specific
(see subsection 3.3.2.2.9) |
| BWR/PWR | Neutron absorbing sheets in spent fuel storage racks | Reduction of neutron absorbing capacity and loss of material due to general corrosion (Boral, boron steel) | Plant specific | Yes, plant specific (see
subsection 3.3.2.2.10)
|
| BWR/PWR | New fuel rack assembly | Loss of material due to general, pitting, and crevice corrosion | Structures monitoring | No |
| BWR/PWR | Spent fuel storage racks and valves in spent fuel pool cooling and cleanup | Crack initiation and growth due to stress corrosion cracking | Water chemistry | No |
| BWR/PWR | Neutron absorbing sheets in spent fuel storage racks | Reduction of neutron absorbing capacity due to Boraflex degradation | Boraflex monitoring | No |
| BWR/PWR | Closure bolting and external surfaces of carbon steel and low-alloy steel components | Loss of material due to boric acid corrosion | Boric acid corrosion | No |
| BWR/PWR | Components in or serviced by closed-cycle cooling water system | Loss of material due to general, pitting, and crevice corrosion, and MIC | Closed-cycle cooling water system | No |
| BWR/PWR | Cranes including bridge and trolleys and rail system in load handling system | Loss of material due to general corrosion and wear | Overhead heavy load and light
load handling systems
|
No |
| BWR/PWR | Components in or serviced by open-cycle cooling water systems | Loss of material due to general, pitting, crevice, and galvanic corrosion, MIC, and biofouling; buildup of deposit due to biofouling | Open-cycle cooling water system | No |
| BWR/PWR | Buried piping and fittings | Loss of material due to general, pitting, and crevice corrosion, and MIC | Buried piping and tanks
surveillance
or Buried piping and tanks inspection |
No
Yes, detection of aging effects and operating experience are to be further evaluated (see subsection 3.3.2.2.11) |
| BWR/PWR | Components in compressed air system | Loss of material due to general and pitting corrosion | Compressed air monitoring | No |
| BWR/PWR | Components (doors and barrier penetration seals) and concrete structures in fire protection | Loss of material due to wear;
hardnening and shrinkage due
to weathering
|
Fire protection | No |
| BWR/PWR | Components in water-based fire protection | Loss of material due to general, pitting, crevice, and galvanic corrosion, MIC, and biofouling | Fire water system | No |
| BWR/PWR | Components in diesel fire system | Loss of material due to galvanic, general, pitting, and crevice corrosion | Fire protection
and fuel oil chemistry |
No |
| BWR/PWR | Tanks in diesel fuel oil system | Loss of material due to general, pitting, and crevice corrosion | Aboveground carbon steel tanks | No |
| BWR/PWR | Closure bolting | Loss of material due to general corrosion; crack initiation and growth due to cyclic loading and SCC | Bolting integrity | No |
| BWR | Components in contact with sodium pentaborate solution in standby liquid control system (BWR) | Crack initiation and growth due to SCC | Water chemistry | No |
| BWR | Components in reactor water cleanup system | Crack initiation and growth due to SCC and IGSCC | Reactor water cleanup system inspection | No |
| BWR | Components in shutdown
cooling system
(older BWR) |
Crack initiation and growth due to SCC | BWR stress corrosion cracking
and
water chemistry |
No |
| BWR | Components in shutdown
cooling system
(older BWR) |
Loss of material due to pitting and crevice corrosion, and MIC | Closed-cycle cooling water system | No |
| BWR/
PWR |
Components (aluminum bronze, brass, cast iron, cast steel) in open-cycle and closed-cycle cooling water systems, and ultimate heat sink | Loss of material due to selective leaching | Selective leaching of materials | No |
| BWR/
PWR |
Fire barriers, walls, ceilings and floors in fire protection | Concrete cracking and spalling due to freeze-thaw, aggressive chemical attack, and reaction with aggregates; loss of material due to corrosion of embedded steel | Fire protection and structures monitoring |
No |
Table 3.3-2. FSAR Supplement for Aging Management of Auxiliary Systems
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Bolting integrity (BWR/PWR) |
This program consists of guidelines on materials selection, strength and hardness properties, installation procedures, lubricants and sealants, corrosion considerations in the selection and installation of pressure-retaining bolting for nuclear applications, and enhanced inspection techniques. This program relies on the bolting integrity program delineated in NUREG-1339 and industry's recommendations delineated in EPRI NP-5769, with the exceptions noted in NUREG-1339 for safety-related bolting and in EPRI TR-104213 for pressure retaining bolting and structural bolting. | Existing program |
| Boraflex monitoring (BWR/PWR) |
The program consists of (1) neutron attenuation testing ("blackness testing") to determine gap formation, (2) sampling for the presence of silica in the spent fuel pool along with boron loss, and (3) monitoring and analysis of criticality to assure that the required 5% subcriticality margin is maintained. This program is implemented in response to GL 96-04. | Existing program |
| Boric acid corrosion
(PWR) |
The program consists of (1) visual inspection of external surfaces that are potentially exposed to borated water leakage, (2) timely discovery of leak path and removal of the boric acid residues, (3) assessment of the damage, and (4) follow-up inspection for adequacy. This program is implemented in response to GL 88-05. | Existing program |
| BWR vessel internals
(BWR) |
The program includes (1) inspection and flaw evaluation in conformance with the guidelines of applicable and staff-approved boiling water reactor vessel and internals project (BWRVIP) documents and (2) monitoring and control of reactor coolant water chemistry in accordance with the guidelines of BWRVIP-29 (EPRI TR-103515) to ensure the long-term integrity and safe operation of boiling water reactor (BWR) vessel internal components. | Existing program |
| Closed-cycle cooling water system (BWR/PWR) | The program relies on preventive measures to minimize corrosion by maintaining inhibitors and by performing non-chemistry monitoring consisting of inspection and nondestructive evaluations based on the guidelines of EPRI-TR-107396 for closed-cycle cooling water systems. | Existing program |
Table 3.3-2. FSAR Supplement for Aging Management of Auxiliary Systems (continued)
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Compressed air monitoring (BWR/PWR) | The program consists of inspection, monitoring, and testing of the entire system, including (1) frequent leak testing valves, piping, and other system components, especially those made of carbon steel; and (2) preventive monitoring that checks air quality at various locations in the system to ensure that oil, water, rust, dirt, and other contaminants are kept within the specified limits. This program is in response to NRC GL 88-14 and INPO's Significant Operating Experience Report (SOER) 88-01. It also relies on the ASME OM Guide Part 17, and ISA-S7.0.1-1996 as guidance for testing and monitoring air quality and moisture. | Existing program |
| Fire protection (BWR/PWR) |
The program includes a fire barrier inspection program and a diesel-driven fire pump inspection program. The fire barrier inspection program requires periodic visual inspection of fire barrier penetration seals, fire barrier walls, ceilings, and floors, and periodic visual inspection and functional tests of fire rated doors to ensure that their operability is maintained. The diesel-driven fire pump inspection program requires that the pump be periodically tested to ensure that the fuel supply line can perform the intended function. The AMP also includes periodic inspection and test of halon/carbon dioxide fire suppression system. | Existing program |
| Fire water system (BWR/PWR) | To ensure no fouling has occurred in the fire protection system, periodic full flow flush test and system performance test are conducted to prevent corrosion from biofouling of components. Also, the system is normally maintained at required operating pressure and is monitored such that loss of system pressure is immediately detected and corrective actions initiated. The AMP relies on testing of water based fire protection system piping and components in accordance with applicable NFPA commitments. In addition, this program will be modified to included (1) portions of the fire protection sprinkler system that are subjected to full flow tests prior to the period of extended operation and (2) portions of the fire protection system exposed to water are internally visually inspected. | Program should be modified before the period of extended operation |
| Fuel oil chemistry (BWR/PWR) | The AMP relies on a combination of surveillance and maintenance procedures. Monitoring and controlling fuel oil contamination in accordance with the guidelines of ASTM Standards D1796, D2276, D2709, and D4057, maintains the fuel oil quality. Exposure to fuel oil contaminants such as water and microbiological organisms is minimized by periodic cleaning/draining of tanks and by verifying the quality of new oil before its introduction into the storage tanks. | Existing program |
| ASME Section XI
Inservice inspection
(ISI)
(BWR/PWR) |
The program consists of periodic volumetric, surface, and/or visual examination of components and their supports for assessment, signs of degradation, and corrective actions. This program is in accordance with ASME Section XI, 1995 edition through the 1996 addenda. | Existing program |
| One-time inspection | To verify the effectiveness of the water chemistry control program by determining if the
aging effect is not
occurring or the aging effect is progressing slowly so that the that the intended function will be
maintained
during the period of extended operation, a one-time inspection of internal surfaces of carbon
steel piping, valve
bodies, pump casings, and tanks is performed using suitable techniques at the most
susceptible locations to
ensure that corrosion is not occurring.
To verify the effectiveness of the fuel oil program by determining if the aging effect is not
occurring or the aging
effect is progressing slowly so that the intended function will be maintained during the period
of extended
operation, a one-time thickness measurement of the tank bottom is performed. |
The inspection should be completed before the period of extended operation |
| Open-cycle cooling
water system
(BWR/PWR) |
The program includes (1) surveillance and control of biofouling, (2) tests to verify heat transfer, (3) routine inspection and maintenance program, (4) system walk down inspection, and (5) review of maintenance, operating, and training practices and procedures. The program provides assurance that the open-cycle cooling water system is in compliance with General Design Criteria and Quality Assurance to ensure that the open-cycle cooling water (or service water) system can be managed for an extended period of operation. This program is in response to NRC GL 89-13. | Existing program |
| Aboveground carbon
steel tanks (BWR/PWR) |
The program includes preventive measures to mitigate corrosion by protecting the external surface of carbon steel components, per standard industry practice, with sealant or caulking at the interface of concrete and component. Visual inspection during periodic system walk downs should be sufficient to monitor degradation of the protective paint, coating, calking, or sealant. Verification of the effectiveness of the program by measuring the thickness of the tank bottoms ensures that degradation is not occurring and that the component intended function will be maintained during the extended period of operation. | Existing program |
| Buried piping and
tanks surveillance
(BWR/PWR) |
The program includes preventive measures to mitigate corrosion by protecting the
external surface of buried
piping and components, e.g., coating, wrapping, and a cathodic protection system. The program also includes surveillance and monitoring of the coating conductance versus time or current. This program is based on standard industry practices as described in NACE-RP-0285-95 and RP-0169-96. |
Existing program |
| Buried piping and tanks inspection | The program includes (1) preventive measures to mitigate corrosion, and (2) periodic inspection to manage the effects of corrosion on the pressure-retaining capacity of buried carbon steel piping and tanks. Preventive measures are in accordance with standard industry practice for maintaining external coatings and wrappings and cathodic protection. As an alternative, buried piping and tanks are inspected visually for any evidence of damage when they are excavated during maintenance and when a pipe is dug up and inspected for any reason with a frequency that is based on operating experience. | Program should be implemented before the period of extended operation |
| Inspection of overhead
heavy load and light
load handling system
(BWR/PWR) |
The program evaluates the effectiveness of the maintenance monitoring program and the effects of past and future usage on the structural reliability of cranes and hoists. The number and magnitude of lifts made by the hoist or crane are also reviewed. Rails and girders are visually inspected on a routine basis for degradation. Functional tests are also performed to assure their integrity. These cranes must also comply with the maintenance rule requirements provided in 10 CFR Part 50.65. | Existing program |
| Plant-specific AMP | The description should contain information associated with the basis for determining that aging effects will be managed during the period of extended operation. | Program should be implemented before the period of extended operation |
| Quality assurance | The 10 CFR Part 50, Appendix B program provides for corrective actions, the confirmation process, and administrative controls for aging management programs for license renewal. The scope of this existing program will be expanded to include nonsafety-related structures and components that are subject to an AMR for license renewal. | Program should be implemented before the period of extended operation |
| Reactor water cleanup system (BWR) | The program includes inservice inspection (ISI) and monitoring and control of reactor coolant water chemistry. Related to the inspection guidelines for RWCU piping welds outboard of the second isolation valve, the program includes measures delineated in NUREG-0313, Rev. 2, and NRC Generic Letter (GL) 88-01 and ISI in conformance with the American Society of Mechanical Engineers (ASME) Section XI. | Existing program |
| Selective leaching of materials | The program includes a hardness measurement of selected components that may be susceptible to selective leaching to determine whether loss of materials is occurring and whether the process will affect the ability of the components to perform their intended function for the period of extended operation. For systems subjected to environments where water is not treated (i.e., the open-cycle cooling water system and the ultimate heat sinks), the program also follows the guidance in NRC GL 89-13. | Program should be implement before the period of extended operation |
| Structures monitoring
(BWR/PWR) |
The program consists of periodic inspection and monitoring the condition of structures and structure component supports to ensure that aging degradation leading to loss of intended functions will be detected and that the extent of degradation can be determined. This program is implemented in accordance with NEI 93-01, Rev. 2 and Regulatory Guide 1.160, Rev. 2. | Existing program |
Table 3.3-2. FSAR Supplement for Aging Management of Auxiliary Systems (continued)
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Water chemistry
(BWR/PWR) |
To mitigate aging effects on component surfaces that are exposed to water as process fluid, chemistry programs are used to control water impurities (e.g., chloride, fluoride, and sulfate) that accelerate corrosion. The water chemistry program relies on monitoring and control of water chemistry to keep peak levels of various contaminants below the system-specific limits based on EPRI guidelines of BWRVIP-29 (TR-103515) for water chemistry in BWRs, TR-105714 for primary water chemistry in PWRs, and TR-102134 for secondary water chemistry in PWRs. | Existing program |
| * An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date. | ||
3.4 Aging Management of Steam and Power Conversion System
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Review Responsibilities
Primary - Branch responsible for materials and chemical engineering
Secondary - Branch responsible for mechanical engineering
3.4.1 Areas of Review
This review plan section addresses the Aging Management Review (AMR) of the steam and power conversion system for license renewal. For a recent vintage plant, the information related to the steam and power conversion system is contained in Chapter 10, "Steam and Power Conversion System," of the plant's FSAR, consistent with the "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants" (NUREG-0800) (Ref. 1). The steam and power conversion systems contained in this review plan section are generally consistent with those contained in NUREG-0800 except for the condenser circulating water and the condensate storage systems. For older plants, the location of applicable information is plant-specific because their FSAR may have predated NUREG-0800. Typical steam and power conversion systems that are subject to an AMR for license renewal are steam turbine, main steam, extraction steam, feedwater, condensate, steam generator blowdown (PWR), and auxiliary feedwater (PWR). The aging management for the steam generator is reviewed following the guidance in section 3.1 of this standard review plan. The aging management for portions of the BWR main steam and main feedwater systems, extending from the reactor vessel to the outermost containment isolation valve, is reviewed separately following the guidance in Section 3.1 of this standard review plan.
The staff has issued a GALL report (Ref. 2) addressing aging management for license renewal. The GALL report documents the staff's basis for determining whether generic existing programs are adequate to manage aging without change, or generic existing programs should be augmented for license renewal. The GALL report may be referenced in a license renewal application, and should be treated in the same manner as an approved topical report.
Because a license renewal applicant may or may not be able to reference the GALL report as explained below, the following areas are reviewed:
3.4.1.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
An applicant may reference the GALL report in a license renewal application to demonstrate that the applicant's programs at its facility correspond to those reviewed and approved in the report, and that no further staff review is required. If the material presented in the GALL report is applicable to the applicant's facility, the staff should find the applicant's reference to the report acceptable. In making this determination, the staff should consider whether the applicant has identified specific programs described and evaluated in the GALL report. The staff, however, should not repeat its review of the substance of the matters described in the report. Rather, the staff should ensure that the applicant verifies that the approvals set forth in the GALL report for generic programs apply to the applicant's programs.
3.4.1.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report provides the basis for identifying those programs that warrant further evaluation during the staff review of a license renewal application. The staff review should focus on augmented programs for license renewal.
3.4.1.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
The GALL report provides a generic staff evaluation of certain aging management programs. If an applicant does not rely on a particular program for license renewal, or if the applicant indicates that the generic staff evaluation of the elements of a particular program does not apply to its plant, the staff should review each such aging management program to which the GALL report does not apply.
The GALL report provides a generic staff evaluation of certain components and aging effects. If an applicant has identified particular components subject to an AMR for its plant that are not addressed in the GALL report, or particular aging effects for a component that are not addressed in the GALL report, the staff should review the applicant's aging management programs applicable to these particular components and aging effects.
3.4.1.4 FSAR Supplement
The FSAR supplement summarizing the programs and activities for managing the effects of aging for the period of extended operation is reviewed.
3.4.2 Acceptance Criteria
The acceptance criteria for the areas of review describe methods for determining whether the applicant has met the requirements of the NRC's regulations in 10 CFR 54.21.
3.4.2.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
Acceptable methods for managing aging of the steam and power conversion system are described and evaluated in Chapter VIII of the GALL report (Ref. 2). In referencing this report, the applicant should indicate that the material presented in the GALL report is applicable to the specific plant involved, and provide the information necessary to adopt the finding of program acceptability as described and evaluated in the report. The applicant should also verify that the approvals set forth in the GALL report for generic programs apply to the applicant's programs. The applicant may reference appropriate programs as described and evaluated in the GALL report.
3.4.2.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report indicates that further evaluation should be performed for:
3.4.2.2.1 Cumulative Fatigue Damage
Fatigue is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The evaluation of this TLAA is addressed separately in Section 4.3 of this standard review plan.
3.4.2.2.2 Loss of Material due to General, Pitting, and Crevice Corrosion
The management of loss of material due to general, pitting, and crevice corrosion should be evaluated further for carbon steel piping and fittings, valve bodies and bonnets, pump casings, pump suction and discharge lines, tanks, tubesheets, channel heads, and shells except for main steam system components and for loss of material due to pitting and crevice corrosion for stainless steel tanks and heat exchanger/cooler tubes. The water chemistry program relies on monitoring and control of water chemistry based on the guidelines in BWRVIP-29 (EPRI TR-103515) (Ref. 3) for water chemistry in BWRs and EPRI guidelines of TR-102134 (Ref. 4) for secondary water chemistry in PWRs to manage the effects of loss of material due to general, pitting, or crevice corrosion. However, corrosion may occur at locations of stagnant flow conditions. Therefore, the effectiveness of the chemistry control program should be verified to ensure that corrosion is not occurring. The GALL report recommends further evaluation of programs to manage loss of material due to general, pitting, and crevice corrosion to verify the effectiveness of the water chemistry program. A one-time inspection of select components and susceptible locations is an acceptable method to ensure that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation.
3.4.2.2.3 Loss of Material due to General, Pitting, and Crevice Corrosion, Microbiologically Influenced Corrosion, and Biofouling
Loss of material due to general corrosion, pitting and crevice corrosion, microbiologically influenced corrosion (MIC), and biofouling could occur in carbon steel piping and fittings for untreated water from the backup water supply in the PWR auxiliary feedwater system. The GALL report recommends further evaluation to ensure that these aging effects are adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
3.4.2.2.4 General Corrosion
Loss of material due to general corrosion could occur on the external surfaces of all carbon steel structures and components, including closure boltings, exposed to operating temperature less that 212°F. The GALL report recommends further evaluation to ensure that this aging effect is adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
3.4.2.2.5 Loss of Material due to General, Pitting, Crevice, and Microbiologically Influenced Corrosion
1. Loss of material due to general corrosion (carbon steel only), pitting and crevice corrosion, and MIC could occur in stainless steel and carbon steel shells, tubes, and tubesheets within the bearing oil coolers (for steam turbine pumps) in the PWR auxiliary feedwater system. The GALL report recommends further evaluation to ensure that these aging effects are adequately managed. Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
2. Loss of material due to general corrosion, pitting and crevice corrosion, and MIC could occur in underground piping and fittings and emergency condensate storage tank in the auxiliary feedwater system and the underground condensate storage tank in the condensate system. The buried piping and tanks inspection program relies on industry practice, frequency of pipe excavation, and operating experience to manage the effects of loss of material from general corrosion, pitting and crevice corrosion, and MIC. The effectiveness of the buried piping and tanks inspection program should be verified to evaluate an applicant's inspection frequency and operating experience with buried components, ensuring that loss of material is not occurring.
3.4.2.2.6 Quality Assurance for Aging Management of Nonsafety-Related Components
Acceptance criteria are described in Branch Technical Position IQMB-1 (Appendix A.2 of this standard review plan.)
3.4.2.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
3.4.2.4 FSAR Supplement
The summary description of the programs and activities for managing the effects of aging for the period of extended operation in the FSAR supplement should be appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the bases for determining that aging effects will be managed during the period of extended operation.
3.4.3 Review Procedures
For each area of review, the following review procedures are to be followed:
3.4.3.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
The applicant may reference the GALL report in its license renewal application, as appropriate. The staff should not repeat its review of the substance of the matters described in this report. If the applicant has provided the information necessary to adopt the finding of program acceptability as described and evaluated in the GALL report, the staff should find the applicant's reference to the report in a license renewal application acceptable. In making this determination, the reviewer verifies that the applicant has provided a brief description of the system, components, materials, and environment. The reviewer also verifies that the applicant has stated that the applicable aging effects and industry and plant-specific operating experience have been reviewed by the applicant and are evaluated in the GALL report. The reviewer verifies that the applicant has identified those aging effects for the steam and power conversion system components that are contained in the GALL report as applicable to its plant. In addition, the reviewer verifies that the applicant has stated that the plant programs covered by the applicant's reference contain the same program elements that the staff evaluated and relied upon in approving the corresponding generic program in the GALL report.
The reviewer should verify that the applicant has stated that certain of its aging management programs contain the same program elements as the corresponding generic program described in the GALL report, and upon which the staff relied in its evaluation. The reviewer should also verify that the applicant has stated that the GALL report is applicable to its plant with respect to these programs. The reviewer verifies that the applicant has identified the appropriate programs as described and evaluated in the GALL report. Programs evaluated in the report regarding the steam and power conversion system components are summarized in Table 3.4-1 of this review plan section. No further staff evaluation is necessary if so recommended in the GALL report.
3.4.3.2 Further Evaluation of Aging Management as Recommended by the GALL Report
3.4.3.2.1 Cumulative Fatigue Damage
Fatigue is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The staff reviews the evaluation of this TLAA separately following the guidance in Section 4.3 of this standard review plan.
3.4.3.2.2 Loss of Material due to General, Pitting, and Crevice Corrosion
The GALL report recommends further evaluation of programs to manage loss of material due to general, pitting, and crevice corrosion of carbon steel piping and fittings, valve bodies and bonnets, pump casings, pump suction and discharge lines, tanks, tubesheets, channel heads, and shells, except for main steam system components, and for loss of material due to pitting and crevice corrosion for stainless steel tanks and heat exchanger/cooler tubes to verify the effectiveness of the water chemistry program. An acceptable verification program consists of a one-time inspection of select components and susceptible locations in the system. The water chemistry program relies on monitoring and control of water chemistry based on BWRVIP-29 (EPRI TR-103515) (Ref. 3) for water chemistry in BWRs and EPRI guidelines of TR-102134 (Ref. 4) for secondary water chemistry in PWRs to manage the effects of loss of material due to general, pitting, or crevice corrosion. However, corrosion may occur at locations of stagnant flow conditions. Therefore, the effectiveness of the chemistry control program should be verified to ensure that significant degradation is not occurring and that the component's intended function will be maintained during the extended period of operation.
The staff reviews the applicant's proposed program to ensure that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation. If an applicant proposes a one-time inspection of select components and susceptible locations to ensure that corrosion is not occurring, the reviewer verifies that the applicant's selection of susceptible locations is based on severity of conditions, time of service, and lowest design margin. The reviewer also verifies that the proposed inspection would be performed using techniques similar to ASME Code and ASTM standards.
3.4.3.2.3 Loss of Material due to General, Pitting, and Crevice Corrosion, Microbiologically Influenced Corrosion, and Biofouling
The GALL report recommends further evaluation of programs to manage the loss of material due to general corrosion, pitting and crevice corrosion, MIC, and biofouling for carbon steel piping and fittings for untreated water from the backup water supply in the PWR auxiliary feedwater system. Such corrosion may be due to untreated water from the backup water supply. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3.4.3.2.4 General Corrosion
The GALL report recommends further evaluation of programs to manage the loss of material due to general corrosion for external surfaces of all carbon steel structures and components, including closure boltings, exposed to operating temperature less that 212°F. Such corrosion may be due to air, moisture, or humidity. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
3.4.3.2.5 Loss of Material due to General, Pitting, Crevice, and Microbiologically Influenced Corrosion
1. The GALL report recommends further evaluation of programs to manage the loss of material due to general corrosion (carbon steel only), pitting and crevice corrosion, and MIC for stainless steel and carbon steel shells, tubes, and tubesheets within the bearing oil coolers (for steam-turbine pumps) in the PWR auxiliary feedwater system. Such corrosion may be due to water contamination that affects the quality of the lubricating oil in the bearing oil coolers. The staff reviews the applicant's proposed program on a case-by-case basis to ensure that an adequate program will be in place for the management of these aging effects.
2. The GALL report recommends further evaluation of programs to manage loss of material due to general corrosion, pitting and crevice corrosion, and MIC of underground piping and fittings and emergency condensate storage tank in the auxiliary feedwater system and underground condensate storage tank in the condensate system to verify the effectiveness of the water chemistry program. The buried piping and tanks inspection program relies on industry practice, frequency of pipe excavation, and operating experience to manage the effects of loss of material from general corrosion, pitting and crevice corrosion, and MIC. The effectiveness of the buried piping and tanks inspection program should be verified to evaluate an applicant's inspection frequency and operating experience with buried components, ensuring that corrosion is not occurring and that the component's intended function will be maintained during the period of extended operation.
3.4.3.2.6 Quality Assurance for Aging Management of Nonsafety-Related Components
An applicant's aging management programs for license renewal should contain the elements of corrective actions, the confirmation process, and administrative controls. Safety-related components are covered by 10 CFR Part 50 Appendix B, which is adequate to address these program elements. However, Appendix B does not apply to nonsafety-related components that are subject to an AMR for license renewal. Nevertheless, an applicant has the option to expand the scope of its 10 CFR Part 50 Appendix B program to include these components and address these program elements. If an applicant chooses this option, the reviewer verifies that the applicant has documented such a commitment in the FSAR supplement. If an applicant chooses alternative means, the branch responsible for quality assurance should be requested to review the applicant's proposal on a case-by-case basis.
3.4.3.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Review procedures are described in Branch Technical Position RLSB-1 (Appendix A.1, of this standard review plan.)
3.4.3.4 FSAR Supplement
The reviewer verifies that the applicant has provided a FSAR supplement for aging management of the steam and power conversion system for license renewal with information equivalent to that in Table 3.4-2 of this review plan section. The reviewer also verifies that the applicant has provided information, equivalent to that in Table 3.4-2, in the FSAR supplement for Subsection 3.4.3.3, "Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report."
The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Table 3.4-2, the applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
3.4.4 Evaluation Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provisions of this review plan section and that the staff's evaluation supports conclusions of the following type, to be included in the staff's safety evaluation report:
The staff concludes that the applicant has demonstrated that the aging effects associated with the steam and power conversion system will be adequately managed so that there is reasonable assurance that these systems will perform their intended functions in accordance with the current licensing basis during the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of the programs and activities for managing the effects of aging for the steam and power conversion system as reflected in the license condition.
3.4.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specified portions of the NRC's regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
3.4.6 References
1. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants," U.S. Nuclear Regulatory Commission, July 1981.
2. NUREG-1801, "Generic Aging Lessons Learned (GALL)," U.S. Nuclear Regulatory Commission, July 2001.
3. BWRVIP-29, BWR Water Chemistry Guidelines-Revision 3 [EPRI TR-103515], Normal and Hydrogen Water Chemistry, Electric Power Research Institute, Palo Alto, CA, February 1994.
4. EPRI TR-102134, PWR Secondary Water Chemistry Guideline-Revision 3, Electric Power Research Institute, Palo Alto, CA, May 1993.
Table 3.4-1. Summary of Aging Management Programs for Steam and Power Conversion System Evaluated in Chapter VIII of the GALL Report
| Type | Component | Aging Effect/ Mechanism |
Aging Management Programs |
Further Evaluation Recommended |
|---|---|---|---|---|
| PWR/BWR | Piping and fittings in main feedwater line, steam line and AFW piping (PWR only) | Cumulative fatigue damage | TLAA, evaluated in accordance with 10 CFR 54.21(c) | Yes, TLAA (see Subsection 3.4.2.2.1) |
| PWR/BWR | Piping and fittings, valve bodies and bonnets, pump casings, tanks, tubes, tubesheets, channel head and shell (except main steam system) | Loss of material due to general (carbon steel only), pitting, and crevice corrosion | Water chemistry and one-time inspection | Yes, detection of aging effects is to be further evaluated (see subsection 3.4.2.2.2) |
| PWR | Auxiliary feedwater (AFW) piping | Loss of material due to general, pitting, and crevice corrosion, MIC, and biofouling | Plant specific | Yes, plant specific
(see subsection 3.4.2.2.3) |
| PWR | Oil coolers in AFW system (lubricating oil side possibly contaminated with water) | Loss of material due to general (carbon steel only), pitting, and crevice corrosion and MIC | Plant specific | Yes, plant specific
(see subsection 3.4.2.2.5.1) |
| BWR/PWR | External surface of carbon steel components | Loss of material due to general corrosion | Plant specific | Yes, plant specific
(see subsection 3.4.2.2.4) |
| BWR/PWR | Carbon steel piping and valve bodies | Wall thinning due to flow-accelerated corrosion | Flow-accelerated corrosion | No |
| BWR/PWR | Carbon steel piping and valve bodies in main steam system | Loss of material due to pitting and crevice corrosion | Water chemistry | No |
| BWR/PWR | Closure bolting in high-pressure or high-temperature systems | Loss of material due to general corrosion; crack initiation and growth due to cyclic loading and/or SCC. | Bolting integrity | No |
| BWR/ PWR |
Heat exchangers and coolers/ condensers serviced by open-cycle cooling water | Loss of material due to general (carbon steel only), pitting, and crevice corrosion, MIC, and biofouling; buildup of deposit due to biofouling | Open-cycle cooling water system | No |
Table 3.4-1. Summary of Aging Management Programs for Steam and Power Conversion System Evaluated in Chapter VIII of the GALL Report (continued)
| Type | Component | Aging Effect/ Mechanism |
Aging Management Programs |
Further Evaluation Recommended |
|---|---|---|---|---|
| BWR/PWR | Heat exchangers and coolers/
condensers serviced by closed-cycle cooling water |
Loss of material due to general (carbon steel only), pitting, and crevice corrosion | Closed-cycle cooling water system | No |
| BWR/PWR | External surface of aboveground condensate storage tank | Loss of material due to general (carbon steel only), pitting, and crevice corrosion | Aboveground carbon steel tanks | No |
| BWR/PWR | External surface of buried condensate storage tank and AFW piping | Loss of material due to general, pitting, and crevice corrosion and MIC | Buried piping and tanks
surveillance
or Buried piping and tanks inspection |
No
Yes, detection of aging effects and operating experience are to be further evaluated (see subsection 3.4.2.2.5.2) |
| PWR | External surface of carbon steel components | Loss of material due to boric acid corrosion | Boric acid corrosion | No |
Table 3.4-2. FSAR Supplement for Aging Management of Steam and Power Conversion System
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Bolting integrity (BWR/PWR) |
This program consists of guidelines on materials selection, strength and hardness properties, installation procedures, lubricants and sealants, corrosion considerations in the selection and installation of pressure-retaining bolting for nuclear applications, and enhanced inspection techniques. This program relies on the bolting integrity program delineated in NUREG-1339 and industry's recommendations delineated in EPRI NP-5769, with the exceptions noted in NUREG-1339 for safety-related bolting and in EPRI TR-104213 for pressure retaining bolting and structural bolting. | Existing program |
| Boric acid corrosion (PWR) |
The program consists of (1) visual inspection external surfaces that are potentially exposed to borated water leakage, (2) timely discovery of leak path and removal of the boric acid residues, (3) assessment of the damage, and (4) follow-up inspection for adequacy. This program is implemented in response to GL 88-05. | Existing program |
| Closed-cycle cooling water system (BWR/PWR) |
The program relies on preventive measures to minimize corrosion by maintaining inhibitors and by performing non-chemistry monitoring consisting of inspection and nondestructive evaluations based on the guidelines of EPRI-TR-107396 for closed-cycle cooling water systems. | Existing program |
| Flow-accelerated corrosion (BWR/PWR) |
The program consists of (1) conduct appropriate analysis and baseline inspection, (2) determine extent of thinning, and replace/repair components, and (3) perform follow-up inspections to confirm or quantify and take longer-term corrective actions. The program relies on implementation of EPRI guidelines of NSAC-202L-R2. | Existing program |
| One-time inspection (BWR/PWR) |
To verify the effectiveness of the water chemistry control program by determining if the aging effect is not occurring or the aging effect is progressing slowly so that the intended function will be maintained during the period of extended operation, a one-time inspection of internal surfaces of piping, valves, pump casings, heat exchangers and tanks is performed using suitable techniques at the most susceptible locations to ensure that the aging effect is not occurring. | The inspection should be completed before the period of extended operation. |
Table 3.4-2. FSAR Supplement for Aging Management of Steam and Power Conversion System (continued)
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Open-cycle cooling water system(BWR/PWR) | The program includes (a) surveillance and control of biofouling, (b) tests to verify heat transfer, (c) routine inspection and maintenance program, (d) system walk down inspection, and (e) review of maintenance, operating, and training practices and procedures. The program provides assurance that the open-cycle cooling water system is in compliance with General Design Criteria and Quality Assurance to ensure that the open-cycle cooling water (or service water) system can be managed for an extended period of operation. This program is in response to NRC GL 89-13. | Existing program |
| Above-ground carbon steel tanks (BWR/PWR) |
The program includes preventive measures to mitigate corrosion by protecting the external surface of carbon steel components, per standard industry practice, with sealant or caulking at the interface of concrete and component. Visual inspection during periodic system walk downs should be sufficient to monitor degradation of the protective paint, coating, calking, or sealant. Verification of the effectiveness of the program by measuring the thickness of the tank bottoms ensures that significant degradation is not occurring and that the component intended function will be maintained during the extended period of operation. | Existing program |
| Buried piping and tanks surveillance (BWR/PWR) |
The program includes preventive measures to mitigate corrosion by protecting the external surface of buried piping and components, e.g., coating, wrapping, and a cathodic protection system. The program also includes surveillance and monitoring of the coating conductance versus time or current. This program is based on standard industry practices as described in NACE-RP-01-69. | Existing program |
| Buried piping and tanks inspection | The program includes (a) preventive measures to mitigate corrosion, and (b) periodic inspection to manage the effects of corrosion on the pressure-retaining capacity of buried carbon steel piping and tanks. Preventive measures are in accordance with standard industry practice for maintaining external coatings and wrappings and cathodic protection. As an alternative, buried piping and tanks are inspected when they are excavated during maintenance and when a pipe is dug up and inspected for any reason with a frequency that is based on operating experience. | Program should be implemented before the period of extended operation. |
| Plant-specific AMP (PWR) |
The description should contain information associated with the bases for determining that aging effects will be managed during the period of extended operation. | Program should be implemented before the period of extended operation. |
| Quality assurance
(BWR/PWR) |
The 10 CFR Part 50 Appendix B program provides for corrective actions, the confirmation process, and administrative controls for aging management programs for license renewal. The scope of this existing program will be expanded to include nonsafety-related structures and components that are subject to an AMR for license renewal. | Program should be implemented before the period of extended operation. |
| Water chemistry (BWR/PWR) |
To mitigate aging effects on component surfaces that are exposed to water as process fluid, chemistry programs are used to control water impurities (e.g., chloride, fluoride, sulfate) that accelerate corrosion. The water chemistry program relies on monitoring and control of water chemistry based on BWRVIP-29 (EPRI TR-103515) for water chemistry in BWRs and EPRI guidelines of TR-102134 for secondary water chemistry in PWRs. | Existing program |
| * An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date. | ||
3.5 Aging Management of Containments, Structures, and Component Supports
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Review Responsibilities
Primary - Branch responsible for structural engineering
Secondary - None
3.5.1 Areas of Review
This review plan section addresses the aging management review (AMR) for structures and component supports. For a recent vintage plant, the information related to structures and component supports is contained in Chapter 3, "Design of Structures, Components, Equipment, and Systems," of the plant's FSAR, consistent with the "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants" (NUREG-0800) (Ref. 1). For older vintage plants, the location of applicable information is plant-specific because their FSAR may have predated NUREG-0800. The scope of this section is PWR and BWR containment structures; Class I structures; and component supports. The PWR containment structures consist of concrete (reinforced or prestressed) and steel containments. The BWR containment structures consist of Mark I steel containments, Mark II concrete (reinforced or prestressed) and steel containments, and Mark III concrete and steel containments (Ref. 2).
The Class I structures are organized into nine groups: Group 1: BWR reactor building, PWR shield building, control room/building; Group 2: BWR reactor building with steel superstructure; Group 3: auxiliary building, diesel generator building, radwaste building, turbine building, switchgear room, auxiliary feedwater pump house, utility/piping tunnels; Group 4: containment internal structures, excluding refueling canal; Group 5: fuel storage facility, refueling canal; Group 6: water-control structures (e.g., intake structure, cooling tower, and spray pond); Group 7: concrete tanks; Group 8: steel tanks; and Group 9: BWR unit vent stack (Ref. 2).
The component supports are organized into seven groups: Group B1.1: supports for ASME Class I piping and components; Group B1.2: supports for ASME Class 2 and 3 piping and components; Group B1.3: supports for ASME Class MC components; Group B2: supports for cable tray, conduit, HVAC ducts, tube track, instrument tubing, non-ASME piping and components; Group B3: anchorage of racks, panels, cabinets, and enclosures for electrical equipment and instrumentation; Group B4: supports for miscellaneous equipment (e.g., EDG, HVAC components); and Group B5: supports for miscellaneous structures (e.g., platforms, pipe whip restraints, jet impingement shields, masonry walls) (Ref. 2).
The staff has issued the GALL report addressing aging management for license renewal (Ref. 2). The GALL report documents the staff's basis for determining whether generic existing programs are adequate to manage aging without change, or generic existing programs should be augmented for license renewal. The GALL report may be referenced in a license renewal application, and should be treated in the same manner as an approved topical report.
Because a license renewal applicant may or may not be able to reference the GALL report as explained below, the following areas are reviewed:
3.5.1.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
The applicant may reference the GALL report in a license renewal application to demonstrate that the applicant's programs at its facility correspond to those reviewed and approved in the report, and that no further staff review is required. If the material presented in the GALL report is applicable to the applicant's facility, the staff should find the applicant's reference to the report acceptable. In making this determination, the staff should consider whether the applicant has identified specific programs described and evaluated in the GALL report. The staff, however, should not repeat its review of the substance of the matters described in the GALL report. Rather, the staff should ensure that the applicant verifies that the approvals set forth in the GALL report for generic programs apply to the applicant's programs.
3.5.1.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report provides the basis for identifying those programs that warrant further evaluation during the staff review of a license renewal application. The staff review should focus on augmented programs for license renewal.
3.5.1.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
The GALL report provides a generic staff evaluation of certain aging management programs. If an applicant does not rely on a particular program for license renewal, or if the applicant indicates that the generic staff evaluation of the elements of a particular program does not apply to its plant, the staff should review each such aging management program to which the GALL report does not apply.
The GALL report provides a generic staff evaluation of certain components and aging effects. If an applicant has identified particular components subject to an AMR for its plant that are not addressed in the GALL report, or particular aging effects for a component that are not addressed in the GALL report, the staff should review the applicant's aging management programs applicable to these particular components and aging effects.
3.5.1.4 FSAR Supplement
The FSAR supplement summarizing the programs and activities for managing the effects of aging for the period of extended operation is reviewed.
3.5.2 Acceptance Criteria
The acceptance criteria for the areas of review describe methods for determining whether the applicant has met the requirements of the NRC's regulations in 10 CFR 54.21.
3.5.2.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
Acceptable methods for managing aging of structures and component supports are described and evaluated in Chapters II and III of the GALL report (Ref. 2). In referencing this report, the applicant should indicate that the material presented in the GALL report is applicable to the specific plant involved, and provide the information necessary to adopt the finding of program acceptability as described and evaluated in the GALL report. The applicant should also verify that the approvals set forth in the GALL report for generic programs apply to the applicant's programs. The applicant may reference appropriate programs as described and evaluated in the GALL report.
3.5.2.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report indicates that further evaluation should be performed for:
3.5.2.2.1 PWR and BWR Containments
3.5.2.2.1.1 Aging of Inaccessible Concrete Areas
Cracking, spalling, and increases in porosity and permeability due to leaching of calcium hydroxide and aggressive chemical attack; and cracking, spalling, loss of bond, and loss of material due to corrosion of embedded steel could occur in inaccessible areas of PWR concrete and steel containments; BWR Mark II concrete containments; and Mark III concrete and steel containments. The GALL report recommends further evaluation of plant-specific programs to manage the aging effects for inaccessible areas if specific criteria defined in the GALL report cannot be satisfied.
3.5.2.2.1.2 Cracking, Distortion, and Increase in Component Stress Level due to Settlement; Reduction of Foundation Strength due to Erosion of Porous Concrete Subfoundations, if Not Covered by Structures Monitoring Program
Cracking, distortion, and increase in component stress level due to settlement could occur in PWR concrete and steel containments and BWR Mark II concrete containments and Mark III concrete and steel containments. Also, reduction of foundation strength due to erosion of porous concrete subfoundations could occur in all types of PWR and BWR containments.
Some plants may rely on a de-watering system to lower the site ground water level. If the plant's CLB credits a de-watering system, the GALL report recommends verification of the continued functionality of the de-watering system during the period of extended operation. The GALL report recommends no further evaluation if this activity is included in the scope of the applicant's structures monitoring program.
3.5.2.2.1.3 Reduction of Strength and Modulus of Concrete Structures due to Elevated Temperature
Reduction of strength and modulus of elasticity due to elevated temperatures could occur in PWR concrete and steel containments and BWR Mark II concrete containments and Mark III concrete and steel containments. The GALL report recommends further evaluation if any portion of the concrete containment components exceeds specified temperature limits, i.e., general area temperature 66°C (150°F) and local area temperature 93°C (200°F).
3.5.2.2.1.4 Loss of Material due to Corrosion in Inaccessible Areas of Steel Containment Shell or Liner Plate
Loss of material due to corrosion could occur in inaccessible areas of the steel containment shell or the steel liner plate for all types of PWR and BWR containments. The GALL report recommends further evaluation of plant-specific programs to manage this aging effect for inaccessible areas if specific criteria defined in the GALL report cannot be satisfied.
3.5.2.2.1.5 Loss of Prestress due to Relaxation, Shrinkage, Creep, and Elevated Temperature
Loss of prestress forces due to relaxation, shrinkage, creep, and elevated temperature for PWR prestressed concrete containments and BWR Mark II prestressed concrete containments is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The evaluation of this TLAA is addressed separately in Section 4.5 of this standard review plan.
3.5.2.2.1.6 Cumulative Fatigue Damage
If included in the current licensing basis, fatigue analyses of containment steel liner plates and steel containment shells (including welded joints) and penetrations (including penetration sleeves, dissimilar metal welds, and penetration bellows) for all types of PWR and BWR containments and BWR vent header and downcomers are TLAAs as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The evaluation of this TLAA is addressed separately in Section 4.6 of this standard review plan.
3.5.2.2.1.7 Cracking due to Cyclic Loading and SCC
Cracking of containment penetrations (including penetration sleeves, penetration bellows, and dissimilar metal welds) due to cyclic loading or SCC could occur in all types of PWR and BWR containments. Cracking could also occur in vent line bellows, vent headers and downcomers due to SCC for BWR containments. A visual VT-3 examination would not detect such cracks. The GALL report recommends further evaluation of the inspection methods implemented to detect these aging effects.
3.5.2.2.2 Class I Structures
3.5.2.2.2.1 Aging of Structures Not Covered by Structures Monitoring Program
The GALL report recommends further evaluation of certain structure/aging effect combinations if they are not covered by the structures monitoring program. This includes (1) scaling, cracking, and spalling due to repeated freeze-thaw for Groups 1-3, 5, 7-9 structures; (2) scaling, cracking, spalling and increase in porosity and permeability due to leaching of calcium hydroxide and aggressive chemical attack for Groups 1-5, 7-9 structures; (3) expansion and cracking due to reaction with aggregates for Groups 1-5, 7-9 structures; (4) cracking, spalling, loss of bond, and loss of material due to corrosion of embedded steel for Groups 1-5, 7-9 structures; (5) cracks, distortion, and increase in component stress level due to settlement for Groups 1-3, 5, 7-9 structures; (6) reduction of foundation strength due to erosion of porous concrete subfoundation for Groups 1-3, 5-9 structures; (7) loss of material due to corrosion of structural steel components for Groups 1-5, 7-8 structures; (8) loss of strength and modulus of concrete structures due to elevated temperatures for Groups 1-5; and (9) crack initiation and growth due to SCC and loss of material due to crevice corrosion of stainless steel liner for Groups 7 and 8 structures. Further evaluation is necessary only for structure/aging effect combinations not covered by the structures monitoring program.
Technical details of the aging management issue are presented in Subsection 3.5.2.2.1.2 for items (5) and (6) and Subsection 3.5.2.2.1.3 for item (8).
3.5.2.2.2.2 Aging Management of Inaccessible Areas
Cracking, spalling, and increases in porosity and permeability due to aggressive chemical attack and cracking, spalling, loss of bond, and loss of material due to corrosion of embedded steel could occur in below-grade inaccessible concrete areas. The GALL report recommends further evaluation to manage these aging effects in inaccessible areas of Groups 1-3, 5, 7-9 structures, if specific criteria defined in the GALL report cannot be satisfied.
3.5.2.2.3 Component Supports
3.5.2.2.3.1 Aging of Supports Not Covered by Structures Monitoring Program
The GALL report recommends further evaluation of certain component support/aging effect combinations if they are not covered by the structures monitoring program. This includes (1) reduction in concrete anchor capacity due to degradation of the surrounding concrete, for Groups B1-B5 supports; (2) loss of material due to environmental corrosion, for Groups B2-B5 supports; and (3) reduction/loss of isolation function due to degradation of vibration isolation elements, for Group B4 supports. Further evaluation is necessary only for structure/aging effect combinations not covered by the structures monitoring program.
3.5.2.2.3.2 Cumulative Fatigue Damage due to Cyclic Loading
Fatigue of component support members, anchor bolts, and welds for Groups B1.1, B1.2, and B1.3 component supports is a TLAA as defined in 10 CFR 54.3 only if a CLB fatigue analysis exists. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The evaluation of this TLAA is addressed separately in Section 4.3 of this standard review plan.
3.5.2.2.4 Quality Assurance for Aging Management of Nonsafety-Related Components
Acceptance criteria are described in Branch Technical Position IQMB-1 (Appendix A.2 of this standard review plan.)
3.5.2.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan.)
3.5.2.4 FSAR Supplement
The summary description of the programs and activities for managing the effects of aging for the period of extended operation in the FSAR supplement should be appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the bases for determining that aging effects are managed during the period of extended operation.
3.5.3 Review Procedures
For each area of review, the following review procedures are to be followed:
3.5.3.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
The applicant may reference the GALL report in its license renewal application, as appropriate. The staff should not repeat its review of the substance of the matters described in the GALL report. If the applicant has provided the information necessary to adopt the finding of program acceptability as described and evaluated in the GALL report, the staff should find the applicant's reference to the report in a license renewal application acceptable. In making this determination, the reviewer verifies that the applicant has provided a brief description of the system, components, materials, and environment. The reviewer also verifies that the applicant has stated that the applicable aging effects and industry and plant-specific operating experience have been reviewed by the applicant and are evaluated in the GALL report. The reviewer verifies that the applicant has identified those aging effects for the structures and component supports that are contained in the report as applicable to its plant. In addition, the reviewer verifies that the applicant has stated that the plant programs covered by the applicant's reference contain the same program elements that the staff evaluated and relied upon in approving the corresponding generic program in the GALL report.
The reviewer should verify that the applicant has stated that certain of its aging management programs contain the same program elements as the corresponding generic program described in the GALL report, and upon which the staff relied in its evaluation. The reviewer should also verify that the applicant has stated that the GALL report is applicable to its plant with respect to these programs. The reviewer verifies that the applicant has identified the appropriate programs as described and evaluated in the GALL report. Programs evaluated in the report regarding the structures and component supports are summarized in Table 3.5-1 of this review plan section. No further staff evaluation is necessary if so recommended in the GALL report.
3.5.3.2 Further Evaluation of Aging Management as Recommended by the GALL Report
3.5.3.2.1 PWR and BWR Containments
3.5.3.2.1.1 Aging of Inaccessible Concrete Areas
The GALL report recommends further evaluation of programs to manage aging effects in inaccessible areas. Possible effects due to leaching of calcium hydroxide and aggressive chemical attack are cracking, spalling, and increases in porosity and permeability. Possible effects due to corrosion of embedded steel in PWR concrete and steel containments and BWR Mark II concrete containments and Mark III concrete and steel containments are cracking, spalling, loss of bond, and loss of material. The current aging management programs that involve detecting aging effects in inaccessible areas consist of Section XI, Subsection IWL examinations of 1992 or later edition of ASME code (Ref. 3), which is in accordance with the requirements of, and is approved in, 10 CFR 50.55a. However, Subsection IWL exempts from examination portions of the concrete containments that are inaccessible (e.g., foundation, exterior walls below grades, concrete covered by liner).
To cover the inaccessible areas, 10 CFR 50.55a(b)(2)(ix) requires that the licensee evaluate the acceptability of inaccessible areas when conditions exist in accessible areas that could indicate the presence of, or result in, degradation to such inaccessible areas. In addition, the GALL report recommends further evaluation of plant-specific programs to manage the aging effects for inaccessible areas if specific criteria defined in the GALL report cannot be satisfied. The reviewer reviews the applicant's proposed aging management program to verify that, where appropriate, an effective inspection program will be implemented to ensure that the aging effects in inaccessible areas are adequately managed during the period of extended operation.
3.5.3.2.1.2 Cracking, Distortion, and Increases in Component Stress Level due to Settlement; Reduction of Foundation Strength due to Erosion of Porous Concrete Subfoundations, if Not Covered by Structures Monitoring Program
If applicable to the applicant's plant, the GALL report recommends aging management of (1) cracking, distortion, and increases in component stress level due to settlement for PWR concrete and steel containments and BWR Mark II concrete containments and Mark III concrete and steel containments and (2) reduction of foundation strength due to erosion of porous concrete subfoundations for all types of PWR and BWR containments If a de-watering system is relied upon for control of settlement and erosion, then proper functioning of the de-watering system should be monitored for the period of extended operation. The reviewer verifies that, if the applicant's plant credits a de-watering system in its CLB, the applicant has committed to monitor the functionality of the de-watering system under the applicant's structures monitoring program. If not, the reviewer evaluates the plant-specific program for monitoring the de-watering system during the period of extended operation.
3.5.3.2.1.3 Reduction of Strength and Modulus of Concrete Structures due to Elevated Temperature
The GALL report recommends further evaluation of programs to manage reduction of strength and modulus of concrete structures due to elevated temperature for PWR concrete and steel containments and BWR Mark II concrete containments and Mark III concrete and steel containments. The GALL report notes that the implementation of Subsection IWL examinations and 10 CFR 50.55a would not be able to detect the reduction of concrete strength and modulus due to elevated temperature and also notes that no mandated aging management exists for managing this aging effect.
The GALL report recommends that a plant-specific evaluation be performed if any portion of the concrete containment components exceeds specified temperature limits, viz., general temperature 66°C (150°F) and local area temperature 93°C (200°F). The reviewer verifies that the applicant's discussion in the renewal application indicates that the affected PWR and BWR containment components are not exposed to temperature that exceeds the temperature limits [operating temperature <66°C (150°F), local area temperature <93°C (200°F)]. For concrete containment components that operate above these temperature limits, the reviewer reviews the applicant's proposed programs on a case-by-case basis to ensure that the effects of elevated temperature will be managed during the period of extended operation.
3.5.3.2.1.4 Loss of Material due to Corrosion in Inaccessible Areas of Steel Containment Shell or Liner Plate
The GALL report identifies programs to manage loss of material due to corrosion of the steel containment shell or the steel liner plate for all types of PWR and BWR containments. The aging management program consists of ASME Section XI, Subsection IWE (Ref. 4) and the requirements of 10 CFR 50.55a for inaccessible areas. Subsection IWE exempts from examination portions of the containments that are inaccessible, such as embedded or inaccessible portions of steel liners and steel containment shells, piping, and valves penetrating or attaching to the containment.
To cover the inaccessible areas, 10 CFR 50.55a(b)(2)(ix) requires that the licensee shall evaluate the acceptability of inaccessible areas when conditions exist in accessible areas that could indicate the presence of, or result in, degradation to such inaccessible areas. In addition, the GALL report recommends further evaluation of plant-specific programs to manage the aging effects for inaccessible areas if specific criteria defined in the GALL report cannot be satisfied. The reviewer reviews the applicant's proposed aging management program to verify that, where appropriate, an effective inspection program has been developed and implemented to ensure that the aging effects in inaccessible areas are adequately managed.
3.5.3.2.1.5 Loss of Prestress due to Relaxation, Shrinkage, Creep, and Elevated Temperature
The GALL report identifies loss of prestress as a TLAA to be performed for the period of license renewal. The reviewer reviews the evaluation of this TLAA separately, following the guidance in Section 4.5 of this standard review plan.
3.5.3.2.1.6 Cumulative Fatigue Damage
Fatigue analyses included in current licensing basis for the containment liner plate and penetrations are TLAAs as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The evaluation of this TLAA is addressed separately in Section 4.6 of this standard review plan.
3.5.3.2.1.7 Cracking due to Cyclic Loading and SCC
The GALL report recommends further evaluation of programs to manage cracking of containment penetrations (including penetration sleeves, penetration bellows, and dissimilar metal welds) due to cyclic loading or SCC for all types of PWR and BWR containments. A similar recommendation for further evaluation of programs to manage cracking of vent line bellows, vent headers and downcomers due to SCC is also provided for BWR containments. Containment ISI and leak rate testing may not be sufficient to detect cracks. The reviewer evaluates the applicant's proposed programs to verify that adequate inspection methods will be implemented to ensure that cracks are detected.
3.5.3.2.2 Class I Structures
3.5.3.2.2.1 Aging of Structures Not Covered by Structures Monitoring Program
The GALL report recommends further evaluation of certain structure/aging effect combinations if they are not covered by the structures monitoring program. This includes (1) scaling, cracking, and spalling due to repeated freeze-thaw for Groups 1-3, 5, 7-9 structures; (2) scaling, cracking, spalling and increase in porosity and permeability due to leaching of calcium hydroxide and aggressive chemical attack for Groups 1-5, 7-9 structures; (3) expansion and cracking due to reaction with aggregates for Groups 1-5, 7-9 structures; (4) cracking, spalling, loss of bond, and loss of material due to corrosion of embedded steel for Groups 1-5, 7-9 structures; (5) cracks, distortion, and increase in component stress level due to settlement for Groups 1-3, 5, 7-9 structures; (6) reduction of foundation strength due to erosion of porous concrete subfoundation for Groups 1-3, 5-9 structures; (7) loss of material due to corrosion of structural steel components for Groups 1-5, 7-8 structures; (8) loss of strength and modulus of concrete structures due to elevated temperatures for Groups 1-5; and (9) crack initiation and growth due to SCC and loss of material due to crevice corrosion of stainless steel liner for Groups 7 and 8 structures. Further evaluation is necessary only for structure/aging effect combinations not covered by the structures monitoring program.
The aging management program consists of a structures monitoring program to verify that the CLB is maintained through periodic testing and inspection of critical plant structures, systems, and components. The reviewer verifies that the applicant has identified the structure/aging effect combinations not within the scope of the applicant's structures monitoring program developed in accordance with the guidance provided in NUMARC 93-01, Rev. 2 (Ref. 5) and RG 1.160, Rev. 2 (Ref. 6). The applicant may choose to expand the scope of its structures monitoring program to include these structure/aging effect combinations. Otherwise, the reviewer evaluates the applicant's proposed program in accordance with the guidance in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan.)
3.5.3.2.2.2 Aging Management of Inaccessible Areas
The GALL report recommends further evaluation of aging management for inaccessible concrete areas, such as foundation and exterior walls below grade exposed to ground water, if specific criteria defined in the GALL report cannot be satisfied. The reviewer reviews the aging management program on a case-by-case basis to ensure that the intended functions will be maintained during the period of the extended operation. The following degradations are managed: cracking, spalling, and increases in porosity and permeability due to aggressive chemical attack; cracking, spalling, loss of bond, and loss of material due to corrosion of embedded steel for Groups 1-3, 5, 7-9 structures.
3.5.3.2.3 Component Supports
3.5.3.2.3.1 Aging of Supports Not Covered by Structures Monitoring Program
The GALL report recommends further evaluation of certain component support/aging effect combinations if they are not covered by the structures monitoring program. This includes (1) reduction in concrete anchor capacity due to degradation of the surrounding concrete, for Groups B1-B5 supports; (2) loss of material due to environmental corrosion, for Groups B2-B5 supports; and (3) reduction/loss of isolation function due to degradation of vibration isolation elements, for Group B4 supports. Further evaluation is necessary only for structure/aging effect combinations not covered by the structures monitoring program.
The aging management program consists of a structures monitoring program to verify that the CLB is maintained through periodic testing and inspection of critical plant structures, systems, and components. The reviewer verifies that the applicant has identified the component support/aging effect combinations not within the scope of the applicant's structures monitoring program developed in accordance with the guidance provided in NUMARC 93-01, Rev. 2 (Ref. 5) and RG 1.160, Rev. 2 (Ref. 6). The applicant may choose to expand the scope of its structures monitoring program to include these component support/aging effect combinations. Otherwise, the reviewer evaluates the applicant's proposed program in accordance with the guidance in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.5.3.2.3.2 Cumulative Fatigue Damage
Fatigue of support members, anchor bolts, and welds for Groups B1.1, B1.2, and B1.3 component supports is a TLAA as defined in 10 CFR 54.3 only if a CLB fatigue analysis exists. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c). The evaluation of this TLAA is addressed separately in Section 4.3 of this standard review plan.
3.5.3.2.4 Quality Assurance for Aging Management of Nonsafety-Related Components
The applicant's aging management programs for license renewal should contain the elements of corrective actions, the confirmation process, and administrative controls. Safety-related components are covered by 10 CFR Part 50 Appendix B, which is adequate to address these program elements. However, Appendix B does not apply to nonsafety-related components that are subject to an AMR for license renewal. Nevertheless, an applicant has the option to expand the scope of its 10 CFR Part 50 Appendix B program to include these components and address these program elements. If the applicant chooses this option, the reviewer verifies that the applicant has documented such a commitment in the FSAR supplement. If the applicant chooses alternative means, the branch responsible for quality assurance should be requested to review the applicant's proposal on a case-by-case basis.
3.5.3.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Review procedures are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.5.3.4 FSAR Supplement
The reviewer verifies that the applicant has provided information, equivalent to that in Table 3.5-2, in the FSAR supplement for aging management of the Structures and Component Supports for license renewal. The reviewer also verifies that the applicant has provided information, equivalent to that in Table 3.5-2, in the FSAR supplement for Subsection 3.5.3.3, "Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report."
The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Table 3.5-2, an applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
3.5.4 Evaluation Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provisions of this review plan section and that the staff's evaluation supports conclusions of the following type, to be included in the staff's safety evaluation report:
The staff concludes that the applicant has demonstrated that the aging effects associated with the structures and component supports will be adequately managed so that there is reasonable assurance that these structures and component supports will perform their intended functions in accordance with the current licensing basis during the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of the programs and activities for managing the effects of aging for the structures and component supports as reflected in the license condition.
3.5.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specified portions of the NRC's regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
3.5.6 References
1. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants," U.S. Nuclear Regulatory Commission, July 1981.
2. NUREG-1801, "Generic Aging Lessons Learned (GALL) Report," U.S. Nuclear Regulatory Commission, July 2001.
3. American Society of Mechanical Engineers, ASME Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, Subsection IWL, Requirements for Class CC Concrete Components of Light-Water Cooled Power Plants, 1992 edition with 1992 addenda, or 1995 edition with 1996 addenda. The ASME Boiler and Pressure Vessel Code, The American Society of Mechanical Engineers, New York, NY.
4. American Society of Mechanical Engineers, ASME Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, Subsection IWE, Requirements for Class MC and Metallic Liners of Class CC Components of Light-Water Cooled Power Plants, 1992 edition with 1992 addenda, or 1995 edition with 1996 addenda. The ASME Boiler and Pressure Vessel Code, The American Society of Mechanical Engineers, New York, NY.
5. NUMARC 93-01, Rev. 2, "Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants" [Line-In/Line-Out Version], Nuclear Energy Institute, April 1996.
6. NRC Regulatory Guide 1.160, Revision 2, "Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," March 1997.
Table 3.5-1. Summary of Aging Management Programs for
Structures and
Component Supports Evaluated in Chapters II and III of the GALL Report
| Type | Component | Aging Effect/ Mechanism |
Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| Common Components of All Types of PWR and BWR Containment | ||||
| BWR/PWR | Penetration sleeves, penetration bellows, and dissimilar metal welds | Cumulative fatigue damage
(CLB fatigue analysis exists) |
TLAA evaluated in accordance with 10 CFR 54.21(c) | Yes, TLAA (see Subsection 3.5.2.2.1.6) |
| BWR/PWR | Penetration sleeves, bellows, and dissimilar metal welds. | Cracking due to cyclic loading, or crack initiation and growth due to SCC | Containment ISI and Containment leak rate test | Yes, detection of aging effects
is to be evaluated (see Subsection 3.5.2.2.1.7) |
| BWR/PWR | Penetration sleeves, penetration bellows, and dissimilar metal welds | Loss of material due to corrosion | Containment ISI and Containment leak rate test | No |
| BWR/PWR | Personnel airlock and equipment hatch | Loss of material due to corrosion |
Containment ISI and Containment leak rate test | No |
| BWR/PWR | Personnel airlock and equipment hatch | Loss of leak tightness in closed position due to mechanical wear of locks, hinges and closure mechanism | Containment leak rate test and Plant Technical Specifications | No |
| BWR/PWR | Seals, gaskets, and moisture barriers | Loss of sealant and leakage through containment due to deterioration of joint seals, gaskets, and moisture barriers | Containment ISI and Containment leak rate test | No |
| PWR Concrete (Reinforced and Prestressed) and Steel Containment BWR Concrete (Mark II and III) and Steel (Mark I, II, and III) Containment | ||||
| BWR/PWR | Concrete elements: foundation, walls, dome. |
Aging of accessible and inaccessible concrete areas due to leaching of calcium hydroxide, aggressive chemical attack, and corrosion of embedded steel | Containment ISI | Yes, if aging mechanism is significant for inaccessible areas (see Subsection 3.5.2.2.1.1) |
|
Table 3.5-1. Summary of Aging Management Programs for Structures and Component Supports Evaluated in Chapters II and III of the GALL Report (continued) |
| Type | Component | Aging Effect/ Mechanism |
Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| BWR/PWR | Concrete elements: foundation |
Cracks, distortion, and increases in component stress level due to settlement | Structures Monitoring | No, if within the scope of the applicant's structures monitoring program (see Subsection 3.5.2.2.1.2) |
| BWR/PWR | Concrete elements: foundation |
Reduction in foundation strength due to erosion of porous concrete subfoundation | Structures Monitoring | No, if within the scope of the applicant's structures monitoring program (see Subsection 3.5.2.2.1.2) |
| BWR/PWR | Concrete elements: foundation, dome, and wall |
Reduction of strength and modulus due to elevated temperature | Plant specific | Yes, for any portions of concrete containment that exceed specified temperature limits (see Subsection 3.5.2.2.1.3) |
| BWR/PWR | Prestressed containment: tendons and anchorage components |
Loss of prestress due to relaxation, shrinkage, creep, and elevated temperature | TLAA evaluated in accordance with 10 CFR 54.21(c) | Yes, TLAA (see Subsection 3.5.2.2.1.5) |
| BWR/PWR | Steel elements: liner plate, containment shell |
Loss of material due to corrosion in accessible and inaccessible areas | Containment ISI and Containment leak rate test | Yes, if corrosion is significant for inaccessible areas (see Subsection 3.5.2.2.1.4) |
| BWR | Steel elements: vent header, drywell head, torus, downcomers, pool shell |
Cumulative fatigue damage
(CLB fatigue analysis exists) |
TLAA evaluated in accordance with 10 CFR 54.21(c) | Yes, TLAA (see Subsection 3.5.2.2.1.6) |
| BWR/PWR | Steel elements: protected by coating |
Loss of material due to corrosion in accessible areas only | Protective coating monitoring and maintenance | No |
| BWR/PWR | Prestressed containment: tendons and anchorage components |
Loss of material due to corrosion of prestressing tendons and anchorage components | Containment ISI | No |
| BWR/PWR | Concrete elements: foundation, dome, and wall |
Scaling, cracking, and spalling due to freeze-thaw; expansion and cracking due to reaction with aggregate | Containment ISI | No |
| BWR | Steel elements: vent line bellows, vent headers, downcomers |
Cracking due to cyclic loads or Crack initiation and growth due to SCC | Containment ISI and Containment leak rate test | Yes, detection of aging effects
is to be evaluated
(see Subsection 3.5.2.2.1.7) |
| BWR | Steel elements: Suppression chamber liner |
Crack initiation and growth due to SCC | Containment ISI and Containment leak rate test | No |
| BWR | Steel elements: drywell head and downcomer pipes |
Fretting and lock up due to wear | Containment ISI | No |
Class I Structures
| BWR/PWR | All Groups except Group 6: accessible interior/exterior concrete & steel components | All types of aging effects | Structures Monitoring |
No, if within the scope of the applicant's structures monitoring program (see Subsection 3.5.2.2.2.1) |
| BWR/PWR | Groups 1-3, 5, 7-9: inaccessible concrete components, such as exterior walls below grade and foundation |
Aging of inaccessible concrete areas due to aggressive chemical attack, and corrosion of embedded steel | Plant-specific | Yes, if an aggressive below-grade environment exists (see Subsection 3.5.2.2.2.2) |
| BWR/PWR | Group 6: all accessible/inacce-ssible concrete, steel, and earthen components | All types of aging effects, including loss of material due to abrasion, cavitation, and corrosion | Inspection of Water-Control Structures or FERC/US Army Corps of Engineers dam inspections and maintenance | No |
| BWR/PWR | Group 5: liners |
Crack initiation and growth from SCC and loss of material due to crevice corrosion | Water Chemistry Program and Monitoring of spent fuel pool water level | No |
| BWR/PWR | Groups 1-3, 5, 6: all masonry block walls |
Cracking due to restraint, shrinkage, creep, and aggressive environment | Masonry Wall | No |
| BWR/PWR | Groups 1-3, 5, 7-9: foundation |
Cracks, distortion, and increases in component stress level due to settlement | Structures Monitoring | No, if within the scope of the applicant's structures monitoring program (see Subsection 3.5.2.2.1.2) |
| BWR/PWR | Groups 1-3, 5-9: foundation |
Reduction in foundation strength due to erosion of porous concrete subfoundation | Structures Monitoring | No, if within the scope of the applicant's structures monitoring program (see Subsection 3.5.2.2.1.2) |
| BWR/PWR | Groups 1-5: concrete |
Reduction of strength and modulus due to elevated temperature | Plant-specific | Yes, for any portions of concrete that exceed specified temperature limits (see Subsection 3.5.2.2.1.3) |
| BWR/PWR | Groups 7, 8: liners |
Crack Initiation and growth due to SCC; Loss of material due to crevice corrosion | Plant-specific | Yes |
| Component Supports |
| BWR/PWR | All Groups: support members: anchor bolts, concrete surrounding anchor bolts, welds, grout pad, bolted connections, etc. |
Aging of component supports | Structures Monitoring | No, if within the scope of the applicant's structures monitoring program (see Subsection 3.5.2.2.3.1) |
| BWR/PWR | Groups B1.1, B1.2, and B1.3: support members: anchor bolts, welds |
Cumulative fatigue damage
(CLB fatigue analysis exists) |
TLAA evaluated in accordance with 10 CFR 54.21(c) | Yes, TLAA (see Subsection 3.5.2.2.3.2) |
| PWR | All Groups: support members: anchor bolts, welds |
Loss of material due to boric acid corrosion | Boric acid corrosion | No |
| BWR/PWR | Groups B1.1, B1.2, and B1.3: support members: anchor bolts, welds, spring hangers, guides, stops, and vibration isolators |
Loss of material due to environmental corrosion; loss of mechanical function due to corrosion, distortion, dirt, overload, etc. | ISI | No |
| BWR/PWR | Group B1.1: high strength low-alloy bolts |
Crack initiation and growth due to SCC | Bolting integrity | No |
Table 3.5-2. FSAR Supplement for Aging Management of Structures and Component Supports
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
PWR and BWR Containment | ||
| Containment inservice inspection
(Containment ISI) |
The ASME Section XI, Subsection IWL program consists of periodic visual inspection of concrete surfaces for reinforced and prestressed concrete containments, and periodic visual inspection and sample tendon testing of unbonded post-tensioning systems for prestressed concrete containments, for signs of degradation, assessment of damage and corrective actions. Measured tendon lift-off forces are compared to predicted tendon forces calculated in accordance with RG 1.35.1. The ASME Section XI, Subsection IWE program consists of periodic visual, surface, and volumetric inspection of pressure retaining components of steel and concrete containments for signs of degradation, assessment of damage and corrective actions. This program is in accordance with ASME Section XI, Subsections IWE and IWL, 1992 edition including 1992 addenda or 1995 edition, including 1996 addenda. | Existing program |
| Containment leak rate test (LRT) | This program consists of monitoring of leakage rates through containment liner/welds, penetrations, fittings, and other access openings for detecting degradation of containment pressure boundary. Corrective actions are taken if leakage rates exceed acceptance criteria. This program is implemented in accordance with 10 CFR Part 50 Appendix J, RG 1.163 and NEI 94-01, Rev. 0. | Existing program |
| Protective coating monitoring and maintenance | This program consists of guidance for selection, application, inspection, and maintenance of protective coatings. This program is implemented in accordance with RG 1.54, Rev. 0 or Rev. 1. | Existing program |
Class I Structures |
| Inspection of water-control structures | The program consists of inspection and surveillance program for dams, slopes, canals, intake structure and other water-control structures associated with emergency cooling water systems or flood protection based on RG 1.127, Rev. 1. | Existing program |
Table 3.5-2. FSAR Supplement for Aging Management of Structures and Component Supports (continued)
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Monitoring of leakage in fuel storage facility | This activity consists of periodic monitoring of leak chase system drain lines and leak detection sump of fuel storage facility and refueling channel to detect SCC and crevice corrosion of stainless steel liners. Alternately, the pool water level may be monitored for evidence of leakage. This activity augments the Water Chemistry Program for aging management of the spent fuel pool liner. | Existing program |
| Water chemistry (BWR/PWR) | To mitigate aging effects on component surfaces that are exposed to water as process fluid, chemistry programs are used to control water impurities (e.g., chloride, fluoride, sulfate) that accelerate corrosion. The water chemistry program relies on monitoring and control of water chemistry based on EPRI guidelines of TR-103515 for water chemistry in BWRs and TR-102134 for secondary water chemistry in PWRs. | Existing program |
| Masonry wall | This program consists of inspections, based on IE Bulletin 80-11 and plant-specific monitoring proposed by IN 87-67, for managing cracking of masonry walls. | Existing program |
Component Supports
| Inservice inspection (ISI) |
This program consists of periodic visual examination of component supports for signs of degradation, evaluation, and corrective actions. This program is in accordance with ASME Section XI, Subsection IWF, 1989 edition through 1995 edition, including 1996 addenda. | Existing program |
| Boric acid corrosion (PWR) | The program consists of (1) visual inspection of external surfaces that are potentially exposed to borated water leakage, (2) timely discovery of leak path and removal of the boric acid residues, (3) assessment of the damage, and (4) follow-up inspection for adequacy. This program is implemented in response to GL 88-05. | Existing program |
| Bolting integrity (BWR/PWR) | This program consists of guidelines on materials selection, strength and hardness properties, installation procedures, lubricants and sealants, corrosion considerations in the selection and installation of pressure-retaining bolting for nuclear applications, and enhanced inspection techniques. This program relies on the bolting integrity program delineated in NUREG-1339 and industry's recommendations delineated in EPRI NP-5769, with the exceptions noted in NUREG-1339 for safety-related bolting and in EPRI TR-104213 for pressure retaining bolting and structural bolting. | Existing program |
Class I Structures and Component Supports
| Structures monitoring | The program consists of periodic inspection and monitoring the condition of structures and structure component supports to ensure that aging degradation leading to loss of intended functions will be detected and that the extent of degradation can be determined. This program is implemented in accordance with NUMARC 93-01, Rev. 2 and RG 1.160, Rev. 2. | Existing program |
PWR and BWR Containment, Class I Structures, and Component Supports
| Quality assurance | The 10 CFR Part 50 Appendix B program provides for corrective actions, the confirmation process, and administrative controls for aging management programs for license renewal. The scope of this existing program will be expanded to include nonsafety-related structures and components that are subject to an AMR for license renewal. | Program should be implemented before the period of extended operation |
* An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
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3.6 Aging Management of Electrical and Instrumentation and Controls
Review Responsibilities
Primary - Branch responsible for electrical engineering
Secondary - None
3.6.1 Areas of Review
This review plan section addresses the aging management review (AMR) of the electrical and instrumentation and controls (I&C). For a recent vintage plant, the information related to the Electrical and I&C is contained in Chapter 7, "Instrumentation and Controls," and Chapter 8, "Electric Power," of the plant's FSAR, consistent with the "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants" (NUREG-0800) (Ref. 1). For older plants, the location of applicable information is plant-specific because their FSAR may have predated NUREG-0800. Typical electrical and I&C components that are subject to an AMR for license renewal are electrical cables and connections.
The staff has issued a GALL report addressing aging management for license renewal (Ref. 2). The GALL report documents the staff's basis for determining whether generic existing programs are adequate to manage aging without change, or generic existing programs should be augmented for license renewal. The GALL report may be referenced in a license renewal application, and should be treated in the same manner as an approved topical report.
Because a license renewal applicant may or may not be able to reference the GALL report as explained below, the following areas are reviewed:
3.6.1.1 Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
An applicant may reference the GALL report in a license renewal application to demonstrate that the applicant's programs at its facility correspond to those reviewed and approved in the report, and that no further staff review is required. If the material presented in the GALL report is applicable to the applicant's facility, the staff should find the applicant's reference to the report acceptable. In making this determination, the staff should consider whether the applicant has identified specific programs described and evaluated in the GALL report. The staff, however, should not repeat its review of the substance of the matters described in the report. Rather, the staff should ensure that the applicant verifies that the approvals set forth in the GALL report for generic programs apply to the applicant's programs.
3.6.1.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report provides the basis for identifying those programs that warrant further evaluation during the staff review of a license renewal application. The staff review should focus on augmented programs for license renewal.
3.6.1.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
The GALL report provides a generic staff evaluation of certain aging management programs. If an applicant does not rely on a particular program for license renewal, or if the applicant indicates that the generic staff evaluation of the elements of a particular program does not apply to its plant, the staff should review each such aging management program to which the GALL report does not apply.
The GALL report provides a generic staff evaluation of certain components and aging effects. If an applicant has identified particular components subject to an AMR for its plant that are not addressed in the GALL report, or particular aging effects for a component that are not addressed in the GALL report, the staff should review the applicant's aging management programs applicable to these particular components and aging effects.
3.6.1.4 FSAR Supplement
The FSAR supplement summarizing the programs and activities for managing the effects of aging for the period of extended operation is reviewed.
3.6.2 Acceptance Criteria
The acceptance criteria for the areas of review describe methods for determining whether the applicant has met the requirements of the NRC's regulations in 10 CFR 54.21.
3.6.2.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
Acceptable methods for managing aging of the electrical and I&C components are described and evaluated in Chapter VI of the GALL report (Ref. 2). In referencing this report, the applicant should indicate that the material presented in the GALL report is applicable to the specific plant involved, and provide the information necessary to adopt the finding of program acceptability as described and evaluated in the report. The applicant should also verify that the approvals set forth in the GALL report for generic programs apply to the applicant's programs. The applicant may reference appropriate programs as described and evaluated in the GALL report.
3.6.2.2 Further Evaluation of Aging Management as Recommended by the GALL Report
The GALL report indicates that further evaluation should be performed for:
3.6.2.2.1 Electrical Equipment Subject to Environmental Qualification
Environmental qualification is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c)(1). The evaluation of this TLAA is addressed separately in Section 4.4 of this standard review plan.
3.6.2.2.2 Quality Assurance for Aging Management of Nonsafety-Related Components
Acceptance criteria are described in Branch Technical Position IQMB-1 (Appendix A.2 of this standard review plan).
3.6.2.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Acceptance criteria are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.6.2.4 FSAR Supplement
The summary description of the programs and activities for managing the effects of aging for the period of extended operation in the FSAR supplement should be appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the bases for determining that aging effects are managed during the period of extended operation.
3.6.3 Review Procedures
For each area of review, the following review procedures are to be followed:
3.6.3.1 Aging Management Programs Evaluated in the GALL Report that Are Relied on for License Renewal
The applicant may reference the GALL report in its license renewal application, as appropriate. The staff should not repeat its review of the substance of the matters described in the report. If the applicant has provided the information necessary to adopt the finding of program acceptability as described and evaluated in the GALL report, the staff should find the applicant's reference to the report in a license renewal application acceptable. In making this determination, the reviewer verifies that the applicant has provided a brief description of the system, components, materials, and environment. The reviewer also verifies that the applicant has stated that the applicable aging effects and industry and plant-specific operating experience have been reviewed by the applicant and are evaluated in the GALL report. The reviewer verifies that the applicant has identified those aging effects for the Electrical and I&C System components that are contained in the report as applicable to its plant. In addition, the reviewer verifies that the applicant has stated that the plant programs covered by the applicant's reference contain the same program elements that the staff evaluated and relied upon in approving the corresponding generic program in the GALL report.
The reviewer should verify that the applicant has stated that certain of its aging management programs contain the same program elements as the corresponding generic program described in the GALL report, and upon which the staff relied in its evaluation. The reviewer should also verify that the applicant has stated that the GALL report is applicable to its plant with respect to these programs. The reviewer verifies that the applicant has identified the appropriate programs as described and evaluated in the GALL report. Programs evaluated in the report regarding the Electrical and I&C System components are summarized in Table 3.6-1 of this review plan section. No further staff evaluation is necessary if so recommended in the GALL report.
3.6.3.2 Further Evaluation of Aging Management as Recommended by the GALL Report
3.6.3.2.1 Electrical Equipment Subject to Environmental Qualification
Environmental qualification is a TLAA as defined in 10 CFR 54.3. TLAAs are required to be evaluated in accordance with 10 CFR 54.21(c)(1). The staff reviews the evaluation of this TLAA separately following the guidance in Section 4.4 of this standard review plan.
3.6.3.2.2 Quality Assurance for Aging Management of Nonsafety-Related Components
The applicant's aging management programs for license renewal should contain the elements of corrective actions, the confirmation process, and administrative controls. Safety-related components are covered by 10 CFR Part 50, Appendix B, which is adequate to address these program elements. However, Appendix B does not apply to non safety-related components that are subject to an AMR for license renewal. Nevertheless, the applicant has the option to expand the scope of its 10 CFR Part 50, Appendix B program to include these components and address these program elements. If the applicant chooses this option, the reviewer verifies that the applicant has documented such a commitment in the FSAR supplement. If the applicant chooses alternative means, the branch responsible for quality assurance should be requested to review the applicant's proposal on a case-by-case basis.
3.6.3.3 Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report
Review procedures are described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
3.6.3.4 FSAR Supplement
The reviewer verifies that the applicant has provided information, equivalent to that in Table 3.6-2, in the FSAR supplement for aging management of the Electrical and I&C System for license renewal. The reviewer also verifies that the applicant has provided information, equivalent to that in Table 3.6-2, in the FSAR supplement for Subsection 3.6.3.3, "Aging Management Evaluations that Are Different from or Not Addressed in the GALL Report."
The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Table 3.6-2, an applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
3.6.4 Evaluation Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provisions of this review plan section, and the staff's evaluation supports conclusions of the following type, to be included in the staff's safety evaluation report:
The staff concludes that the applicant has demonstrated that the aging effects associated with the Electrical and I&C System will be adequately managed so that there is reasonable assurance that these systems will perform their intended functions in accordance with the current licensing basis during the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of the programs and activities for managing the effects of aging for the Electrical and I&C System, as reflected in the license conditions.
3.6.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specified portions of the NRC's regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
3.6.6 References
1. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants," U.S. Nuclear Regulatory Commission, July 1981.
2. NUREG-1801, "Generic Aging Lessons Learned (GALL)," U.S. Nuclear Regulatory Commission, July 2001.
Table 3.6-1. Summary of Aging Management Programs for the Electrical Components Evaluated in Chapter VI of the GALL Report
| Type | Component | Aging Effect/ Mechanism | Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| BWR/PWR | Electrical equipment subject to 10 CFR 50.49 environmental qualification (EQ) requirements | Degradation due to various aging mechanisms | Environmental qualification of electric components | Yes, TLAA (see Subsection 3.6.2.2.1) |
| BWR/PWR | Electrical cables and
connections not subject to
10 CFR 50.49 EQ requirements |
Embrittlement, cracking, melting, discoloration, swelling, or loss of dielectric strength leading to reduced insulation resistance (IR); electrical failure caused by thermal/ thermoxidative degradation of organics; radiolysis and photolysis (ultraviolet [UV] sensitive materials only) of organics; radiation-induced oxidation; moisture intrusion | Aging management program
for electrical cables and
connections not subject to
10 CFR 50.49 EQ requirements |
No |
| BWR/PWR | Electrical cables used in
instrumentation circuits not
subject to 10 CFR 50.49 EQ requirements that are sensitive to reduction in conductor insulation resistance (IR) |
Embrittlement, cracking,
melting, discoloration, swelling, or loss of dielectric strength leading to reduced IR; electrical failure caused by thermal/thermoxidative degradation of organics; radiation-induced oxidation; moisture intrusion |
Aging management program
for electrical cables used in
instrumentation circuits not
subject to 10 CFR 50.49 EQ requirements |
No |
| BWR/PWR | Inaccessible medium-voltage
(2 kV to 15 kV) cables (e.g.,
installed in conduit or direct
buried) not subject to
10 CFR 50.49 EQ requirements |
Formation of water trees, localized damage leading to electrical failure (breakdown of insulation); water trees caused by moisture intrusion | Aging management program
for inaccessible medium-voltage cables not subject to
10 CFR 50.49 EQ requirements |
No |
Table 3.6-1. Summary of Aging Management Programs for the Electrical Components
Evaluated in Chapter VI of the GALL Report (continued)
| Type | Component | Aging Effect/ Mechanism | Aging Management Programs | Further Evaluation Recommended |
|---|---|---|---|---|
| PWR | Electrical connectors not
subject to 10 CFR 50.49 EQ requirements that are exposed to borated water leakage |
Corrosion of connector contact surfaces caused by intrusion of borated water | Boric acid corrosion | No |
Table 3.6-2. FSAR Supplement for Aging Management of Electrical and Instrumentation and Control System
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Aging management program for non-environmentally qualified electrical cables and connections exposed to an adverse localized environment caused by heat, radiation, or moisture. | Accessible electrical cables and connections installed in adverse localized environments are visually inspected at least once every 10 years for cable and connection jacket surface anomalies, such as embrittlement, discoloration, cracking, swelling, or surface contamination, which are precursor indications of conductor insulation aging degradation from heat, radiation or moisture. An adverse localized environment is a condition in a limited plant area that is significantly more severe than the specified service condition for the electrical cable or connection. | First inspection for license renewal should be completed before the period of extended operation |
| Aging management program for non-environmentally qualified electrical cables used in instrumentation circuits that are sensitive to reduction in conductor insulation resistance, and are exposed to an adverse localized environment caused by heat, radiation, or moisture. | Electrical cables used in circuits with sensitive, low-level signals, such as radiation monitoring and nuclear instrumentation, are tested as part of the instrumentation loop calibration at the normal calibration frequency, which provides sufficient indication of the need for corrective actions based on acceptance criteria related to instrumentation loop performance. | First tests for license renewal should be completed before the period of extended operation |
| Aging management program for non-environmentally qualified inaccessible medium-voltage cables exposed to an adverse localized environment caused by moisture and voltage exposure | In-scope, medium-voltage cables exposed to significant moisture and significant voltage are tested at least once every 10 years to provide an indication of the condition of the conductor insulation. The specific type of test must be based on technology that is state-of-the-art at the time the test is performed, and must be approved by the NRC staff. Significant moisture is defined as periodic exposures that last more than a few days (e.g., cable in standing water). Periodic exposures that last less than a few days (e.g., normal rain and drain) are not significant. Significant voltage exposure is defined as being subjected to system voltage for more than 25% of the time. The moisture and voltage exposures described as significant in these definitions are not significant for medium-voltage cables that are designed for these conditions (e.g., continuous wetting and continuous energization are not significant for submarine cables). | First tests for license renewal should be completed before the period of extended operation |
|
Table 3.6-2. FSAR Supplement for Aging Management of Electrical and Instrumentation and Control System (continued) |
| Program | Description of Program | Implementation Schedule* |
|---|---|---|
| Boric acid corrosion. | The program consists of (1) visual inspection of external surfaces that are potentially exposed to borated water leakage, (2) timely discovery of leak path and removal of the boric acid residues, (3) assessment of the damage, and (4) follow-up inspection for adequacy. This program is implemented in response to GL 88-05. | Existing program |
| Quality assurance | The 10 CFR Part 50, Appendix B program provides for corrective actions, the confirmation process, and administrative controls for aging management programs for license renewal. The scope of this existing program will be expanded to include non safety-related structures and components that are subject to an AMR for license renewal. | Program should be implemented before the period of extended operation |
| * An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date. | ||
Chapter 4: Time-limited Aging Analyses
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4.1 Identification of Time-limited Aging Analyses
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Review Responsibilities
Primary - Branch responsible for materials and chemical engineering
Secondary - Other branches responsible for engineering, as appropriate
4.1.1 Areas of Review
This review plan section addresses the identification of time-limited aging analyses (TLAAs). The technical review of TLAAs is addressed in section 4.2 through 4.7. As explained in more detail below, the list of TLAAs are certain plant-specific safety analyses that are based on an explicitly assumed 40-year plant life (for example, aspects of the reactor vessel design). Pursuant to 10 CFR 54.21(c)(1), a license renewal applicant is required to provide a list of TLAAs, as defined in 10 CFR 54.3. The area relating to the identification of TLAAs is reviewed.
TLAAs may have evolved since issuance of a plant's operating license. As indicated in 10 CFR 54.30, the adequacy of the plant's CLB, which includes TLAAs, is not an area within the scope of the license renewal review. Any question regarding the adequacy of the CLB must be addressed under the backfit rule (10 CFR 50.109) and is separate from the license renewal process.
In addition, pursuant to 10 CFR 54.21(c)(2), an applicant must provide a list of plant-specific exemptions granted under 10CFR50.12 that are based on TLAAs. However, the initial license renewal applicants have found no such exemptions for their plants.
It is an applicant's option to include more analyses than those required by 10 CFR 54.21(c)(1). The staff should focus its review to confirm that the applicant did not omit any TLAAs, as defined in 10 CFR 54.3.
4.1.2 Acceptance Criteria
The acceptance criteria for the areas of review described in Subsection 4.1.1 of this review plan section delineate acceptable methods for meeting the requirements of the NRC's regulations in 10 CFR 54.21(c)(1). For the applicant's list of exemptions to be acceptable, the staff should have reasonable assurance that there has been no omission of TLAAs from that list.
Pursuant to 10 CFR 54.3, TLAAs are those licensee calculations and analyses that:
1. Involve systems, structures, and components within the scope of license renewal, as delineated in 10 CFR 54.4(a);
2. Consider the effects of aging;
3. Involve time-limited assumptions defined by the current operating term, for example, 40 years;
4. Were determined to be relevant by the licensee in making a safety determination;
5. Involve conclusions or provide the basis for conclusions related to the capability of the system, structure, or component to perform its intended function(s), as delineated in 10 CFR 54.4(b); and
6. Are contained or incorporated by reference in the CLB.
4.1.3 Review Procedures
For each area of review described in Subsection 4.1.1, the reviewer should adhere to the following review procedures:
The reviewer should use the plant UFSAR and other CLB documents, such as staff SERs, in performing the review. The reviewer should select analyses that the applicant did not identify as TLAAs that are likely to meet the six criteria identified in Subsection 4.1.2. The reviewer verifies that the selected analyses, not identified by the applicant as TLAAs, do not meet at least one of the following criteria (Ref. 1).
Sections 4.2 through 4.6 identify typical types of TLAAs for most plants. Information on the licensee's methodology for identifying TLAAs may also be useful in identifying calculations that did not meet six criteria below.
1. Involve systems, structures, and components within the scope of license renewal, as delineated in 10 CFR 54.4(a). Chapter 2 of this standard review plan provides the reviewer guidance on the scoping and screening methodology, and on plant level and various system level scoping results.
2. Consider the effects of aging. The effects of aging include, but are not limited to: loss of material, loss of toughness, loss of prestress, settlement, cracking, and loss of dielectric properties.
3. Involve time-limited assumptions defined by the current operating term (for example, 40 years). The defined operating term should be explicit in the analysis. Simply asserting that a component is designed for a service life or plant life is not sufficient. The assertion should be supported by calculations or other analyses that explicitly include a time limit.
4. Were determined to be relevant by the licensee in making a safety determination. Relevancy is a determination that the applicant should make based on a review of the information available. A calculation or analysis is relevant if it can be shown to have a direct bearing on the action taken as a result of the analysis performed. Analyses are also relevant if they provide the basis for a licensee's safety determination and, in the absence of the analyses, the licensee might have reached a different safety conclusion.
5. Show capability of the system, structure, or component to perform its intended function(s), as delineated. Involve conclusions or provide the basis for conclusions related to the 10 CFR 54.4(b). Analyses that do not affect the intended functions of systems, structures, or components are not TLAAs.
6. Are contained or incorporated by reference in the CLB. Plant-specific documents contained or incorporated by reference in the CLB include, but are not limited to: FSAR, NRC SERs, Technical Specifications, the fire protection plan/hazards analyses, correspondence to and from the NRC, the quality assurance plan, and topical reports included as references to the FSAR. Calculations and analyses that are not in the CLB or not incorporated by reference are not TLAAs. If a code of record is in the FSAR for particular groups of structures or components, reference material includes all calculations required by that code of record for those structures and components.
TLAAs that need to be addressed are not necessarily those analyses that have been
previously reviewed or approved by the NRC. The following examples
illustrate TLAAs that need to be addressed and were not previously reviewed and approved by
the NRC:
- The FSAR states that the design complies with a certain national code and standard. A
review of the code and standard reveals that an analysis or calculation
is required. Some of these calculations or analysis will be TLAAs. The actual calculation was
performed by the licensee to meet code and standard
requirements. The specific calculation was not referenced in the FSAR. The NRC had not
reviewed the calculation.
- In response to a generic letter, a licensee submitted a letter to the NRC committing to perform a TLAA that would address the concern in the generic letter. The NRC had not documented a review of the licensee's response and had not reviewed the actual analysis.
The following examples illustrate analyses that are not TLAAs and need not
be addressed under 10 CFR 54.21(c):
- Population projections (Section 2.1.3 of NUREG-0800) (Ref. 2).
- Cost-benefit analyses for plant modifications.
- Analysis with time-limited assumptions defined short of the current operating term of the plant, for example, an analysis for a component based on a service life that would not reach the end of the current operating term.
The number and type of TLAAs vary depending on the plant-specific CLB. All six criteria set forth in 10 CFR 54.3 (and repeated in Subsection 4.1.2 of this review plan section) must be satisfied to conclude that a calculation or analysis is a TLAA. Table 4.1-1 provides examples of how these six criteria may be applied (Ref. 1). Table 4.1-2 provides a list of potential TLAAs (60 FR 22480). Table 4.1-3 provides a list of other plant-specific TLAAs that have been identified by the initial license renewal applicants. Table 4.1-2 and 4.1-3 provide examples of analyses that potentially could be TLAAs for a particular plant. However, TLAAs are plant-specific and depend on an applicant's CLB. It is not expected that all applicants would identify all the analyses in these tables as TLAAs for their plants. Also, an applicant may have performed specific TLAAs for its plant that are not shown in these tables.
Staff members from other branches of the Division of Engineering will be reviewing the application in their assigned areas without examining the identification of TLAAs. However, they may come across situations in which they may question why the applicant did not identify certain analyses as TLAAs. The reviewer should coordinate the resolution of any such questions with these other staff members and determine whether these analyses should be evaluated as TLAAs.
In order to determine whether there is reasonable assurance that the applicant has identified the TLAAs for its plant, the reviewer should find that the analyses omitted from the applicant's list are not TLAAs.
Should an applicant identify a TLAA that is also a basis for a plant-specific exemption granted pursuant to 10 CFR 50.12 and the exemption is in effect, the reviewer verifies that the applicant has also identified that exemption pursuant to 10 CFR 54.21(c)(2). However, the initial license renewal applicants have found no such exemptions for their plants.
4.1.4 Evaluation Findings
The reviewer verifies that the applicant has provided sufficient information to satisfy the provisions of this review plan section, and that the staff's evaluation supports conclusions of the following type, to be included in the staff's safety evaluation report, as appropriate:
The staff concludes that the applicant has provided an acceptable list of TLAAs as defined in 10 CFR 54.3, and that no 10 CFR 50.12 exemptions have been granted on the basis of a TLAA, as defined in 10 CFR 54.3.
4.1.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
4.1.6 References
1. NEI 95-10, Revision 3, "Industry Guideline for Implementing the Requirements of 10 CFR Part 54 - The License Renewal Rule," Nuclear Energy Institute, March 2001.
2. NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports Nuclear Power Plants," July 1981.
Table 4.1-1. Identification of Potential Time-Limited Aging Analyses and Basis for Disposition
| Example | Disposition |
|---|---|
| NRC correspondence requests a utility to justify that unacceptable cumulative wear did not occur during the design life of control rods. | Does not qualify as a TLAA because the design life of control rods is less than 40 years. Therefore, does not meet criterion (3) of the TLAA definition in 10 CFR 54.3. |
| Maximum wind speed of 100 mph is expected to occur once per 50 years. | Not a TLAA because it does not involve an aging effect. |
| Correspondence from the utility to the NRC states that the membrane on the containment basemat is certified by the vendor to last for 40 years. | The membrane was not credited in any safety evaluation, and therefore the analysis is not considered a TLAA. This example does not meet criterion (4) of the TLAA definition in 10 CFR 54.3. |
| Fatigue usage factor for the pressurizer surge line was determined not to be an issue for the current license period in response to NRC Bulletin 88-11. | This example is a TLAA because it meets all 6 criteria in the definition of TLAA in 10 CFR 54.3. The utility's fatigue design basis relies on assumptions defined by the 40-year operating life for this component, which is the current operating term. |
| Containment tendon lift-off forces are calculated for the 40-year life of the plant. These data are used during Technical Specification surveillance for comparing measured to predicted lift-off forces. | This example is a TLAA because it meets all 6 criteria of the TLAA definition in 10 CFR 54.3. The lift-off force curves are currently limited to 40-year values, and are needed to perform a required Technical Specification surveillance. |
Table 4.1-2. Potential Time-Limited Aging Analyses
| Reactor vessel neutron embrittlement |
| Concrete containment tendon prestress |
| Metal fatigue |
| Environmental qualification of electrical equipment |
| Metal corrosion allowance |
| Inservice flaw growth analyses that demonstrate structure stability for 40 years |
| Inservice local metal containment corrosion analyses |
| High-energy line-break postulation based on fatigue cumulative usage factor |
Table 4.1-3. Additional Examples of Plant-Specific TLAAs as Identified by the Initial License Renewal Applicants
| Intergranular separation in the heat-affected zone (HAZ) of reactor vessel low-alloy steel under austenitic SS cladding. Low-temperature overpressure protection (Ltop) analyses |
| Fatigue analysis for the main steam supply lines to the turbine-driven auxiliary feedwater pumps |
| Fatigue analysis of the reactor coolant pump flywheel |
| Fatigue analysis of polar crane |
| Flow-induced vibration endurance limit, transient cycle count assumptions, and ductility reduction of fracture toughness for the reactor vessel internals |
| Leak before break |
| Fatigue analysis for the containment liner plate |
| Containment penetration pressurization cycles |
| Reactor vessel circumferential weld inspection relief (BWR) |
4.2 Reactor Vessel Neutron Embrittlement Analysis
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Review Responsibilities
Primary - Branch responsible for materials and chemical engineering
Secondary - Branch responsible for reactor systems
4.2.1 Areas of Review
During plant service, neutron irradiation reduces the fracture toughness of ferritic steel in the reactor vessel beltline region of light-water nuclear power reactors. Areas of review to ensure that the reactor vessel has adequate fracture toughness to prevent brittle failure during normal and off-normal operating conditions are (1) upper-shelf energy, (2) PTS for PWRs, (3) heat-up and cool-down (pressure-temperature limits) curves, and (4) BWR Vessel and Internals Project (VIP) VIP-05 analysis for elimination of circumferential weld inspection and analysis of the axial welds.
The adequacy of the analyses for these four areas are reviewed for the period of extended operation.
The branch responsible for reactor systems should review neutron fluence and dosimetry information in the application.
4.2.2 Acceptance Criteria
The acceptance criteria for the areas of review described in Subsection 4.2.1 of this review plan section delineate acceptable methods for meeting the requirements of the NRC's regulation in 10 CFR 54.21(c)(1).
4.2.2.1 Time-Limited Aging Analysis
Pursuant to 10 CFR 54.21(c)(1)(i) - (iii), an applicant must demonstrate one of the following:
(i) The analyses remain valid for the period of extended operation;
(ii) The analyses have been projected to the end of the extended period of operation; or
(iii) The effects of aging on the intended function(s) will be adequately managed for the period of extended operation.
For the first three areas of review for the analysis of reactor vessel neutron embrittlement, the specific acceptance criteria depend on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii).
4.2.2.1.1 Upper-Shelf Energy
10 CFR Part 50 Appendix G (Ref. 1) paragraph IV.A.1 requires that the reactor vessel beltline materials must have a Charpy upper-shelf energy of no less than 68 J (50 ft-lb) throughout the life of the reactor vessel, unless otherwise approved by the NRC.
4.2.2.1.1.1 10 CFR 54.21 (c)(1)(i)
The existing upper-shelf energy analysis remains valid during the period of extended operation because the neutron fluence projected to the end of the period of extended operation is bound by the fluence assumed in the existing analysis.
4.2.2.1.1.2 10 CFR 54.21(c)(1)(ii)
The upper-shelf energy is reevaluated to consider the period of extended operation in accordance with 10 CFR Part 50 Appendix G.
4.2.2.1.1.3 10 CFR 54.21(c)(1)(iii)
Acceptance criteria under 10 CFR 54.21(c)(1)(iii) have yet to be developed. They will be evaluated on a case-by-case basis to ensure that the aging effects will be managed such that the intended function(s) will be maintained during the period of extended operation.
4.2.2.1.2 Pressurized Thermal Shock (for PWRs)
For PWRs, 10 CFR 50.61 (Ref. 2) requires that the "reference temperature RTPTS" for reactor vessel beltline materials be less than the "PTS screening criteria" at the expiration date of the operating license, unless otherwise approved by the NRC. The "PTS screening criteria" are 132°C (270°F) for plates, forgings, and axial weld materials, or 149°C(300°F) for circumferential weld materials. The regulations require updating of the PTS assessment upon a request for a change in the expiration date of a facility's operating license. Therefore, the RTPTS value must be calculated for the entire life of the facility, including the period of extended operation.
4.2.2.1.2.1 10 CFR 54.21(c)(1)(i)
The existing PTS analysis remains valid during the period of extended operation because the neutron fluence projected to the end of the period of extended operation is bound by the fluence assumed in the existing analysis.
4.2.2.1.2.2 10 CFR 54.21(c)(1)(ii)
The PTS analysis is reevaluated to consider the period of extended operation in accordance with 10 CFR 50.61. An analysis is performed in accordance with RG 1.154 (Ref. 3) if the "PTS screening criteria" in 10 CFR 50.61 are exceeded during the period of extended operation.
4.2.2.1.2.3 10 CFR 54.21(c)(1)(iii)
Acceptance criteria under 10 CFR 54.21(c)(1)(iii) have yet to be developed. They will be evaluated on a case-by-case basis to ensure that the aging effects will be managed such that the intended function(s) will be maintained during the period of extended operation.
4.2.2.1.3 Pressure-Temperature (P-T) Limits
10 CFR Part 50 Appendix G (Ref. 1) requires that the reactor pressure vessel (RPV) be maintained within established pressure-temperature (P-T) limits including during heatup and cooldown. These limits specify the maximum allowable pressure as a function of reactor coolant temperature. As the reactor pressure vessel becomes embrittled and its fracture toughness is reduced, the allowable pressure (given the required minimum temperature) is reduced.
4.2.2.1.3.1 10 CFR 54.21(c)(1)(i)
The existing P-T limits are valid during the period of extended operation because the neutron fluence projected to the end of the period of extended operation is bound by the fluence assumed in the existing analysis.
4.2.2.1.3.2 10 CFR 54.21(c)(1)(ii)
The P-T limits are reevaluated to consider the period of extended operation in accordance with 10 CFR Part 50 Appendix G (Ref. 1).
4.2.2.1.3.3 10 CFR 54.21(c)(1)(iii)
Not applicable: Updated P-T limits for the period of extended operation must be available prior to entering the period of extended operation. (It is not necessary to implement P-T limits to carry the reactor vessel through 60 years at the time of application. The updated limits must be contained in a pressure-temperature limit report (PTLR) or in the technical specification (TS) prior to the period of extended operation.)
4.2.2.1.4 Elimination of Circumferential Weld Inspection (for BWRs)
Some BWRs have an approved technical alternative which eliminates the reactor vessel circumferential shell weld inspections for the current license term because they satisfy the limiting conditional failure probability for the circumferential welds at the expiration of the current license, based on BWRVIP-05 and the extent of neutron embrittlement (Refs. 4-6). An applicant for renewal of a license to operate such a BWR may provide justification to extend this relief into the period of extended operation. The staff is currently reviewing BWRVIP-74, which addresses this issue in the context of license renewal (Ref. 7). Section A.4.5 of Report BWRVIP-74 indicates that the staff's SER conservatively evaluated BWR RPV's to have 64 effective full power years (EFPY), which is 10 EFPY greater than what is realistically expected for the end of the license renewal period. Since this was a generic analysis, the licensee must provide plant-specific information to demonstrate that the circumferential beltline weld materials meet the criteria specified in the report and that operator training and procedures will be utilized during the license renewal term to limit the frequency for cold over-pressure events.
4.2.2.1.5 Axial Welds (for BWRs)
The staff's SER contained in a letter to Carl Terry dated March 7, 2000 (Ref. 8) discussed the staff's concern related to RPV failure frequency for axial welds and the BWRVIP's analysis of the RPV failure frequency of axial welds. The SER indicates that the RPV failure frequency due to failure of the limiting axial welds in the BWR fleet at the end of 40 years of operation is less than 5 x 10-6 per reactor year, given the assumptions on flaw density, distribution, and location described in the SER. Since the BWRVIP analysis was generic, the licensee must monitor axial beltline weld embrittlement. The applicant may provide plant-specific information to demonstrate that the axial beltline weld materials at the extended period of operation meet the criteria specified in the report or have a program to monitor axial weld embrittlement relative to the values specified by the staff in its May 7, 2000, (Ref. 8) letter.
4.2.2.2 FSAR Supplement
The specific criterion for meeting 10 CFR 54.21(d) is:
The summary description of the evaluation of TLAAs for the period of extended operation in the FSAR supplement is appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the TLAAs regarding the basis for determining that the applicant has made the demonstration required by 10 CFR 54.21(c)(1).
4.2.3 Review Procedures
For each area of review described in Subsection 4.2.1, the following review procedures should be followed.
4.2.3.1 Time-Limited Aging Analysis
For the first three areas of review for the analysis of reactor vessel neutron embrittlement, the review procedures depend on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii).
4.2.3.1.1 Upper-Shelf Energy
4.2.3.1.1.1 10 CFR 54.21(c)(1)(i)
The projected neutron fluence at the end of the period of extended operation is reviewed to verify that it is bound by the fluence assumed in the existing upper-shelf energy analysis.
4.2.3.1.1.2 10 CFR 54.21(c)(1)(ii)
The documented results of the revised upper-shelf energy analysis based on the projected neutron fluence at the end of the period of extended operation is reviewed for compliance with 10 CFR Part 50 Appendix G. The applicant may use RG 1.99 Rev. 2 (Ref. 9) to project upper-shelf energy to the end of the period of extended operation. The applicant may also use the ASME Code Section XI Appendix K (Ref. 10) for evaluating upper-shelf energy. The staff should review the applicant's methodology for this evaluation.
4.2.3.1.1.3 10 CFR 54.21(c)(1)(iii)
The applicant's proposal to demonstrate that the effects of aging on the intended function(s) will be adequately managed for the period of extended operation will be reviewed on a case-by-case basis.
4.2.3.1.2 Pressurized Thermal Shock (for PWRs)
4.2.3.1.2.1 10 CFR 54.21(c)(1)(i)
The documented results of the projected neutron fluence at the end of the period of extended operation is reviewed to verify that it is bound by the fluence assumed in the existing PTS analysis.
4.2.3.1.2.2 10 CFR 54.21(c)(1)(ii)
The documented results of the revised PTS analysis based on the projected neutron fluence at the end of the period of extended operation is reviewed for compliance with 10 CFR 50.61. There are two methodologies from 10 CFR 50.61 that can be used in the PTS analysis based on the projected neutron fluence at the end of the period of extended operation. RTNDT is the reference temperature (NDT means nil-ductility temperature) used as an indexing parameter to determine the fracture toughness and the amount of embrittlement of a material. RTPTS is the reference temperature used in the PTS analysis and is related to RTNDT at the end of life.
The first methodology does not rely on plant-specific surveillance data to calculate delta RTNDT (i.e., the mean value of the adjustment or shift in reference temperature caused by irradiation). The delta RTNDT is determined by multiplying a chemistry factor from the tables in 10 CFR 50.61 by a fluence factor calculated from the neutron flux using an equation.
The second methodology relies on plant-specific surveillance data to determine the delta RTNDT. In this methodology, two or more sets of surveillance data are needed. A surveillance datum consists of a measured delta RTNDT for a corresponding neutron fluence. 10 CFR 50.61 specifies a procedure and a criterion for determining whether the surveillance data are credible. For the surveillance data to be defined as credible, the difference in the predicted value and the measured value for delta RTNDT must be less than 28°F for weld metal. When a credible surveillance data set exists, the chemistry factor can be determined from these data in lieu of a value from the table in 10 CFR 50.61. Then the standard deviation of the increase in the RTNDT can be reduced from 28°F to 14°F for welds.
If the "PTS screening criteria" in 10 CFR 50.61 are exceeded during the period of extended operation, an analysis based on RG 1.154 (Ref. 3) is reviewed.
4.2.3.1.2.3 10 CFR 54.21(c)(1)(iii)
The applicant's proposal to demonstrate that the effects of aging on the intended function(s) will be adequately managed for the period of extended operation will be reviewed on a case-by-case basis. If the projected reference temperature exceeds the screening criterion established in 10 CFR 50.61, the applicant is required to implement such flux reduction programs as are reasonably practicable to avoid exceeding the screening criterion. The schedule for implementation of such programs may take into account the schedule and anticipated approval by the Director, NRR, of detailed plant-specific analyses to demonstrate acceptable risk with RTPTS above the screening limit. If the applicant cannot avoid exceeding the screening criteria by using a flux reduction program, it must submit a safety analysis to determine what actions are necessary to prevent potential failure of the reactor vessel. 10 CFR 50.61 also permits the licensee to perform a thermal annealing treatment to recover fracture toughness, subject to the requirements of 10 CFR 50.66.
4.2.3.1.3 Pressure-temperature (P-T) Limits
4.2.3.1.3.1 10 CFR 54.21(c)(1)(i)
The documented results of the projected neutron fluence at the end of the period of extended operation is reviewed to verify that it is bound by the embrittlement assumed in the existing P-T limit analysis.
4.2.3.1.3.2 10 CFR 54.21(c)(1)(ii)
The documented results of the revised P-T limit analysis based on the projected reduction in fracture toughness at the end of the period of extended operation is reviewed for compliance with 10 CFR Part 50 Appendix G.
4.2.3.1.3.3 10 CFR 54.21(c)(1)(iii)
Not applicable.
4.2.3.1.4 Elimination of Circumferential Weld Inspection (for BWRs)
To demonstrate that the vessel has not been embrittled beyond the basis for the technical alternative and that cold over-pressure events are not likely to occur during the license renewal term, the applicant should provide: (1) a comparison of the neutron fluence, initial RTNDT , chemistry factor amounts of copper and nickel, delta RTNDT, and mean RTNDT of the limiting circumferential weld at the end of the license renewal period to the 64 EFPY reference case in Appendix E of the staff's SER, (2) an estimate of conditional failure probability of the RPV at the end of the license renewal term based on the comparison of the mean RTNDT for the limiting circumferential welds and the reference case, and (3) a description of procedures and training that will be utilized during the license renewal term to limit the frequency of cold over-pressure events to the amount specified in the staff's SER. The staff should ensure that the applicant's plant is bound by the BWRVIP analysis and that the applicant has committed to actions that are the basis for the staff approval.
4.2.3.1.5 Axial Welds (for BWRs)
To demonstrate that the vessel has not been embrittled beyond the basis for the staff and BWRVIP analyses, the applicant should provide: (1) a comparison of the neutron fluence, initial RTNDT, chemistry factor amounts of copper and nickel, delta RTNDT, and mean RTNDT of the limiting axial weld at the end of the license renewal period to the reference case in the BWRVIP and staff analyses and (2) an estimate of conditional failure probability of the RPV at the end of the license renewal term based on the comparison of the mean RTNDT for the limiting axial welds and the reference case. If this comparison does not indicate that the RPV failure frequency for axial welds is less than 5 x 10-6 per reactor year, the applicant should provide a probabilistic analysis to determine the RPV failure frequency for axial welds. The staff should ensure that the applicant's plant is bound by the BWRVIP analysis or that the applicant has committed to a program to monitor axial weld embrittlement relative to the values specified by the staff in its May 7, 2000, letter.
4.2.3.2 FSAR Supplement
The reviewer verifies that the applicant has provided information to be included in the FSAR supplement that includes a summary description of the evaluation of the reactor vessel neutron embrittlement TLAA. Table 4.2-1 of this review plan section contains examples of acceptable FSAR supplement information for this TLAA. The reviewer verifies that the applicant has provided a FSAR supplement with information equivalent to that in Table 4.2-1.
The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Table 4.2-1, an applicant need not incorporate the implementation schedule into its FSAR. However, the review should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
4.2.4 Evaluation Findings
The reviewer verifies that the applicant has provided sufficient information to satisfy the provisions of this review plan section and that the staff's evaluation supports conclusions of the following type, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), to be included in the staff's safety evaluation report:
The staff concludes that the applicant has provided an acceptable demonstration, pursuant to 10 CFR 54.21(c)(1), that, for the reactor vessel neutron embrittlement TLAA, [choose which is appropriate] (i) the analyses remain valid for the period of extended operation, (ii) the analyses have been projected to the end of the period of extended operation, or (iii) the effects of aging on the intended function(s) will be adequately managed for the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of the reactor vessel neutron embrittlement TLAA evaluation for the period of extended operation as reflected in the license condition.
4.2.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
4.2.6 References
1. 10 CFR Part 50 Appendix G, "Fracture Toughness Requirements."
2. 10 CFR 50.61, "Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events."
3. Regulatory Guide 1.154, "Format and Content of Plant-Specific Pressurized Thermal Shock Safety Analysis Reports for Pressurized Water Reactors," January 1987.
4. BWRVIP-05, "BWR Vessel and Internals Project, BWR Reactor Pressure Vessel Shell Weld Inspection Recommendations (BWRVIP-05)," Boiling Water Reactor Owners Group, September 28, 1995.
5. Letter to Carl Terry of Niagara Mohawk Power Company, from Gus C. Lainas of NRC, dated July 28, 1998.
6. Generic Letter 98-05, "Boiling Water Reactor Licensees Use of the BWRVIP-05 Report to Request Relief from Augmented Examination Requirements on Reactor Pressure Vessel Circumferential Shell Welds," Nuclear Regulatory Commission, November 10, 1998.
7. BWRVIP-74, "BWR Reactor Pressure Vessel Inspection and Flaw Evaluation Guidelines," Boiling Water Reactor Owners Group, September 1999.
8. Letter to Carl Terry of Niagara Mohawk Power Company, from Jack R. Strosnider, Jr., of NRC, dated March 7, 2000.
9. Regulatory Guide 1.99 Rev. 2, "Radiation Embrittlement of Reactor Vessel Materials," May, 1988.
10. Appendix K of ASME Code, Section XI, "Rules for Inservice Inspection of Nuclear Power Plant Components."
Table 4.2-1. Examples of FSAR Supplement for Reactor Vessel Neutron Embrittlement TLAA Evaluation
| TLAA | Description of Evaluation |
Implementation Schedule* |
|---|---|---|
| Upper-shelf energy | 10 CFR Part 50 Appendix G paragraph IV.A.1 requires that the reactor vessel beltline materials must have Charpy upper-shelf energy of no less than 50 ft-lb (68 J) throughout the life of the reactor vessel unless otherwise approved by the NRC. The upper-shelf energy has been determined to exceed 50 ft-lb (68 J) to the end of the period of extended operation. | Completed |
| Pressurized thermal shock (for PWRs) | For PWRs, 10 CFR 50.61 requires the "reference temperature RTPTS" for reactor vessel beltline materials be less than the "PTS screening criteria" at the expiration date of the operating license unless otherwise approved by the NRC. The "PTS screening criteria" are 270°F (132°C) for plates, forgings, and axial weld materials, or 300°F (149°C) for circumferential weld materials. The "reference temperature" has been determined to be less than the "PTS screening criteria" at the end of the period of extended operation. | Completed |
| Pressure-temperature (P-T) limits |
10 CFR Part 50 Appendix G requires that heatup and cooldown of the RPV be accomplished within established P-T limits. These limits specify the maximum allowable pressure as a function of reactor coolant temperature. As the RPV becomes embrittled and its fracture toughness is reduced, the allowable pressure is reduced. 10 CFR Part 50 Appendix G requires periodic update of P-T limits based on projected embrittlement and data from a material surveillance program. The P-T limits will be updated to consider the period of extended operation. | Update should be completed before the period of extended operation. |
| Elimination of circumferential weld inspection and analysis of axial welds (for BWRs) | NRC has granted relief from the reactor vessel circumferential shell weld inspections because the applicant has demonstrated through plant-specific analysis that the plant meets BWRVIP-74 as approved by the NRC and has provided sufficient information that the probability of vessel failure due to embrittlement of axial welds is low. | Completed |
* An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
4.3 Metal Fatigue Analysis
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Review Responsibilities
Primary - Branch responsible for mechanical engineering
Secondary - None
4.3.1 Areas of Review
A metal component subjected to cyclic loading at loads less than the static design load may fail because of fatigue. Metal fatigue of components may have been evaluated based on an assumed number of transients or cycles for the current operating term. The validity of such metal fatigue analysis is reviewed for the period of extended operation.
The metal fatigue analysis review includes, as appropriate, a review of in service flaw growth analyses, reactor vessel underclad cracking analysis, reactor vessel internals fatigue analysis, postulated high energy line break, leak-before-break, RCP flywheel , and metal bellows.
4.3.1.1 Time-Limited Aging Analysis
Metal components may be designed or analyzed based on guidance in the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code or the American National Standards Institute (ANSI) requirements. These codes contain explicit metal fatigue or cyclic considerations based on TLAAs.
4.3.1.1.1 ASME Section III, Class 1
ASME Class 1 components, which include core support structures, are analyzed for metal fatigue. ASME Section III (Ref. 1) requires a fatigue analysis for Class 1 components that considers all transient loads based on the anticipated number of transients. A Section III Class 1 fatigue analysis requires the calculation of the "cumulative usage factor" (CUF) based on the fatigue properties of the materials and the expected fatigue service of the component. The ASME Code limits the CUF to a value of less than one for acceptable fatigue design. The fatigue resistance of these components during the period of extended operation is an area of review.
4.3.1.1.2 ANSI B31.1
ANSI B31.1 (Ref. 2) applies only to piping. It does not require an explicit fatigue analysis. It specifies allowable stress levels based on the number of anticipated thermal cycles. The specific allowable stress reductions due to thermal cycles are listed in Table 4.3-1. For example, the allowable stress would be reduced by a factor of 1.0, i.e., no reduction, for piping that is not expected to experience more than 7,000 thermal cycles during plant service, but would be reduced to half of the maximum allowable static stress for 100,000 or more thermal cycles. The fatigue resistance of these components during the period of extended operation is an area of review.
4.3.1.1.3 Other Evaluations Based on CUF
The codes also contain metal fatigue analysis requirements based on a CUF calculation [the 1969 edition of ANSI B31.7 (Ref. 3) for Class 1 piping, ASME NC-3200 vessels, ASME NE-3200 Class MC components, and metal bellows designed to ASME NC-3649.4(e)(3), ND-3649.4(e)(3), or NE-3366.2(e)(3)]. For these components, the discussion relating to ASME Section III, Class 1 in Subsection 4.3.1.1.1 of this review plan section applies.
4.3.1.1.4 ASME Section III, Class 2 and 3
ASME Section III, Class 2 and 3 piping cyclic design requirements are similar to those for ANSI B31.1. The discussion relating to B31.1 in Subsection 4.3.1.1.2 of this review plan section applies.
4.3.1.2 Generic Safety Issue
The fatigue design criteria for nuclear power plant components has changed as the industry consensus codes and standards have evolved. The fatigue design criteria for a specific component depend on the version of the design code that applied to that component, i.e., the code of record. There is a concern that the effects of the reactor coolant environment on the fatigue life of components were not adequately addressed by the code of record.
The NRC has decided that the adequacy of the code of record relating to metal fatigue is a potential safety issue to be addressed by the current regulatory process for operating reactors (Refs. 4 and 5). The effects of fatigue for the initial 40-year initial reactor license period were studied and resolved under Generic Safety Issue (GSI)-78, "Monitoring of Fatigue Transient Limits for reactor coolant system," and GSI-166, "Adequacy of Fatigue Life of Metal Components" (Ref. 6). GSI-78 addressed whether fatigue monitoring was necessary at operating plants. As part of the resolution of GSI-166, an assessment was made of the significance of the more recent fatigue test data on the fatigue life of a sample of components in plants where Code fatigue design analysis had been performed. The efforts on fatigue life estimation and ongoing issues under GSI-78 and GSI-166 for 40-year plant life were addressed separately under a staff generic task action plan (Refs. 7 and 8). The staff documented its completion of the fatigue action plan in SECY-95-245 (Ref. 9).
SECY-95-245 was based on a study described in NUREG/CR-6260, "Application of NUREG/CR-5999 Interim Fatigue Curves to Selected Nuclear Power Plant Components" (Ref. 10). In NUREG/CR-6260, sample locations with high fatigue usage were evaluated. Conservatisms in the original fatigue calculations, such as actual cycles versus assumed cycles, were removed, and the fatigue usage was recalculated using a fatigue curve considering the effects of the environment. The staff found that most of the locations would have a CUF of less than the ASME Code limit of 1.0 for 40 years. On the basis of the component assessments, supplemented by a 40-year risk study, the staff concluded that a backfit of the environmental fatigue data to operating plants could not be justified. However, because the staff was less certain that sufficient excessive conservatisms in the original fatigue calculations could be removed to account for an additional 20 years of operation for renewal, the staff recommended in SECY-95-245 that the samples in NUREG/CR-6260 should be evaluated considering environmental effects for license renewal. GSI-190, "Fatigue Evaluation of Metal Components for 60-year Plant Life," was established to address the residual concerns of GSI-78 and GSI-166 regarding the environmental effects on fatigue of pressure boundary components for 60 years of plant operation.
The scope of GSI-190 included design basis fatigue transients. It studied the probability of fatigue failure and its effect on core damage frequency (CDF) of selected metal components for 60-year plant life. The results showed that some components have cumulative probabilities of crack initiation and through-wall growth that approach one within the 40- and 60-year period. The maximum failure rate (through-wall cracks per year) was in the range of 10-2 per year, and those failures were generally associated with high cumulative usage factor locations and components with thinner walls, i.e., pipes more vulnerable to through-wall cracks. In most cases, the leakage from these through-wall cracks is small and not likely to lead to core damage. It was concluded that no generic regulatory action is required and that GSI-190 is resolved based on results of probabilistic analyses and sensitivity studies, interactions with the industry (NEI and EPRI), and different approaches available to licensees to manage the effects of aging (Refs. 11 and 12).
However, the calculations supporting resolution of this issue, which included consideration of environmental effects, indicate the potential for an increase in the frequency of pipe leaks as plants continue to operate. Thus, the staff concluded that licensees is to address the effects of coolant environment on component fatigue life as aging management programs are formulated in support of license renewal.
The applicant's consideration of the effects of coolant environment on component fatigue life for license renewal is an area of review.
4.3.1.3 FSAR Supplement
Detailed information on the evaluation of TLAAs is contained in the renewal application. A summary description of the evaluation of TLAAs for the period of extended operation is contained in the applicant's FSAR supplement. The FSAR supplement is an area of review.
4.3.2 Acceptance Criteria
The acceptance criteria for the areas of review described in Subsection 4.3.1 of this review plan section delineate acceptable methods for meeting the requirements of the NRC's regulations in 10 CFR 54.21(c)(1).
4.3.2.1 Time-Limited Aging Analysis
Pursuant to 10 CFR 54.21(c)(1)(i) - (iii), an applicant must demonstrate one of the following:
(i) the analyses remain valid for the period of extended operation,
(ii) the analyses have been projected to the end of the extended period of operation, or
(iii) the effects of aging on the intended function(s) will be adequately managed for the period of extended operation.
Specific acceptance criteria for metal fatigue are:
4.3.2.1.1 ASME Section III, Class 1
For components designed or analyzed to ASME Class 1 requirements, the acceptance criteria, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), are:
4.3.2.1.1.1 10 CFR 54.21(c)(1)(i)
The existing CUF calculations remain valid because the number of assumed transients would not be exceeded during the period of extended operation.
4.3.2.1.1.2 10 CFR 54.21(c)(1)(ii)
The CUF calculations have been reevaluated based on an increased number of assumed transients to bound the period of extended operation. The resulting CUF remains less than unity for the period of extended operation.
4.3.2.1.1.3 10 CFR 54.21(c)(1)(iii)
In Chapter X of the GALL report (Ref. 13), the staff has evaluated a program that monitors and tracks the number of critical thermal and pressure transients for the selected reactor coolant system components. The staff has determined that it is an acceptable aging management program to address metal fatigue of the reactor coolant system components according to 10 CFR 54.21(c)(1)(iii). The GALL report may be referenced in a license renewal application and should be treated in the same manner as an approved topical report. In referencing the GALL report, the applicant should indicate that the material referenced is applicable to the specific plant involved and should provide the information necessary to adopt the finding of program acceptability as described and evaluated in the report. The applicant should also verify that the approvals set forth in the GALL report for the generic program apply to the applicant's program.
4.3.2.1.2 ANSI B31.1
For piping designed or analyzed to B31.1 requirements, the acceptance criteria, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), are:
4.3.2.1.2.1 10 CFR 54.21(c)(1)(i)
The existing fatigue strength reduction factors remain valid because the number of cycles would not be exceeded during the period of extended operation.
4.3.2.1.2.2 10 CFR 54.21(c)(1)(ii)
The fatigue strength reduction factors have been reevaluated based on an increased number of assumed thermal cycles and Table 4.3-1 to bound the period of extended operation. The adjusted fatigue strength reduction factors are such that the component design basis remains valid during the period of extended operation.
4.3.2.1.2.3 10 CFR 54.21(c)(1)(iii)
The effects of aging on the intended function(s) will be adequately managed for the period of extended operation. The component could be replaced and the allowable stresses for the replacement will be sufficient as required by the code during the period of extended operation.
Alternative acceptance criteria under 10 CFR 54.21(c)(1)(iii) have yet to be developed. They will be evaluated on a case-by-case basis to ensure that the aging effects will be managed such that the intended functions(s) will be maintained during the period of extended operation.
4.3.2.1.3 Other Evaluations Based on CUF
The acceptance criteria in Subsection 4.3.2.1.1 of this review plan section apply.
4.3.2.1.4 ASME Section III, Class 2 and 3
The acceptance criteria in Subsection 4.3.2.1.2 of this review plan section apply.
4.3.2.2 Generic Safety Issue
The staff recommendation for the closure of GSI-190 is contained in a December 26, 1999 memorandum from Ashok Thadani to William Travers (Ref. 11). The staff recommended that licensees address the effects of the coolant environment on component fatigue life as aging management programs are formulated in support of license renewal. One method acceptable to the staff for satisfying this recommendation is to assess the impact of the reactor coolant environment on a sample of critical components. These critical components should include, as a minimum, those selected in NUREG/CR-6260 (Ref. 10). The sample of critical components can be evaluated by applying environmental correction factors to the existing ASME Code fatigue analyses. Formulas for calculating the environmental life correction factors for carbon and low-alloy steels are contained in NUREG/CR-6583 (Ref. 14) and those for austenitic SSs are contained in NUREG/CR-5704 (Ref. 15).
4.3.2.3 FSAR Supplement
The specific criterion for meeting 10 CFR 54.21(d) is:
The summary description of the evaluation of TLAAs for the period of extended operation in the FSAR supplement is appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the TLAAs regarding the basis for determining that the applicant has made the demonstration required by 10 CFR 54.21(c)(1).
4.3.3 Review Procedures
For each area of review described in Subsection 4.3.1, the following review procedures should be followed:
4.3.3.1 Time-Limited Aging Analysis
4.3.3.1.1 ASME Section III, Class 1
For components designed or analyzed to ASME Class 1 requirements, the review procedures, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), are:
4.3.3.1.1.1 10 CFR 54.21(c)(1)(i)
The operating transient experience and a list of the assumed transients used in the existing CUF calculations for the current operating term are reviewed to ensure that the number of assumed transients would not be exceeded during the period of extended operation.
4.3.3.1.1.2 10 CFR 54.21(c)(1)(ii)
The operating transient experience and a list of the increased number of assumed transients projected to the end of the period of extended operation are reviewed to ensure that the transient projection is adequate. The revised CUF calculations based on the projected number of assumed transients are reviewed to ensure that the CUF remains less than one at the end of the period of extended operation.
The code of record should be used for the reevaluation, or the applicant may update to a later code edition pursuant to 10 CFR 50.55a. In the latter case, the reviewer verifies that the requirements in 10 CFR 50.55a are met.
4.3.3.1.1.3 10 CFR 54.21(c)(1)(iii)
The applicant may reference the GALL report in its license renewal application, as appropriate. The review should verify that the applicant has stated that the report is applicable to its plant with respect to its program that monitors and tracks the number of critical thermal and pressure transients for the selected reactor coolant system components. The reviewer verifies that the applicant has identified the appropriate program as described and evaluated in the GALL report. The reviewer also ensures that the applicant has stated that its program contains the same program elements that the staff evaluated and relied upon in approving the corresponding generic program in the GALL report. No further staff evaluation is necessary.
4.3.3.1.2 ANSI B31.1
For piping designed or analyzed to ANSI B31.1 requirements, the review procedures, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), are:
4.3.3.1.2.1 10 CFR 54.21(c)(1)(i)
The operating cyclic experience and a list of the assumed thermal cycles used in the existing allowable stress determination are reviewed to ensure that the number of assumed thermal cycles would not be exceeded during the period of extended operation.
4.3.3.1.2.2 10 CFR 54.21(c)(1)(ii)
The operating cyclic experience and a list of the increased number of assumed thermal cycles projected to the end of the period of extended operation are reviewed to ensure that the thermal cycle projection is adequate. The revised allowable stresses based on the projected number of assumed thermal cycles and Table 4.3-1 are reviewed to ensure that they remain sufficient as required by the code during the period of extended operation.
The code of record should be used for the reevaluation, or the applicant may update to a later code edition pursuant to 10 CFR 50.55a. In the latter case, the reviewer verifies that the requirements in 10 CFR 50.55a are met.
4.3.3.1.2.3 10 CFR 54.21(c)(1)(iii)
The applicant's proposed program to ensure that the effects of aging on the intended function(s) will be adequately managed for the period of extended operation is reviewed. If the applicant proposed a component replacement before it exceeds the assumed thermal cycles, the reviewer verifies that the allowable stresses for the replacement will remain sufficient as required by the code during the period of extended operation. Other applicant-proposed programs will be reviewed on a case-by-case basis.
4.3.3.1.3 Other Evaluations Based on CUF
The review procedures in Subsection 4.3.3.1.1 of this review plan section apply.
4.3.3.1.4 ASME Section III, Class 2 and 3
The review procedures in Subsection 4.3.3.1.2 of this review plan section apply.
4.3.3.2 Generic Safety Issue
The reviewer verifies that the applicant has addressed the staff recommendation for the closure of GSI-190 contained in a December 26, 1999 memorandum from Ashok Thadani to William Travers (Ref. 11). The reviewer verifies that the applicant has addressed the effects of the coolant environment on component fatigue life as aging management programs are formulated in support of license renewal. If an applicant has chosen to assess the impact of the reactor coolant environment on a sample of critical components, the reviewer verifies the following:
1. The critical components include, as a minimum, those selected in NUREG/CR-6260 (Ref. 10).
2. The sample of critical components have been evaluated by applying environmental correction factors to the existing ASME Code fatigue analyses.
3. Formulas for calculating the environmental life correction factors are those contained in NUREG/CR-6583 (Ref. 14) for carbon and low-alloy steels, and in NUREG/CR-5704 (Ref. 15) for austenitic SSs.
4.3.3.3 FSAR Supplement
The reviewer verifies that the applicant has provided information, to be included in the FSAR supplement, that includes a summary description of the evaluation of the metal fatigue TLAA. Table 4.3-2 contains examples of acceptable FSAR supplement information for this TLAA. The reviewer verifies that the applicant has provided a FSAR supplement with information equivalent to that in Table 4.3-2. The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Table 4.3-2, an applicant need not incorporate the implementation schedule into its FSAR. However, the review should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation.
The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
4.3.4 Evaluation Findings
The reviewer verifies that the applicant has provided sufficient information to satisfy the provisions of this review plan section and that the staff's evaluation supports conclusions of the following type, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), to be included in the staff's safety evaluation report:
The staff concludes that the applicant has provided an acceptable demonstration, pursuant to 10 CFR 54.21(c)(1), that, for the metal fatigue TLAA, [choose which is appropriate] (i) the analyses remain valid for the period of extended operation, (ii) the analyses have been projected to the end of the period of extended operation, or (iii) the effects of aging on the intended function(s) will be adequately managed for the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of the metal fatigue TLAA evaluation for the period of extended operation as reflected in the license condition.
4.3.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
4.3.6 References
1. ASME Boiler and Pressure Vessel Code, Section III, "Rules for Construction of Nuclear Power Plant Components," American Society of Mechanical Engineers.
2. ANSI/ASME B31.1, "Power Piping," American National Standards Institute.
3. ANSI/ASME B31.7-1969, "Nuclear Power Piping," American National Standards Institute.
4. SECY-93-049, "Implementation of 10 CFR Part 54, 'Requirements for Renewal of Operating Licenses for Nuclear Power Plants,'" March 1, 1993.
5. Staff Requirements Memorandum from Samuel J. Chilk, dated June 28, 1993.
6. NUREG-0933, "A Prioritization of Generic Safety Issues," Supplement 20, July 1996.
7. Letter from William T. Russell of NRC to William Rasin of the Nuclear Management and Resources Council, dated July 30, 1993.
8. SECY-94-191, "Fatigue Design of Metal Components," July 26, 1994.
9. SECY-95-245, "Completion of The Fatigue Action Plan," September 25, 1995.
10. NUREG/CR-6260, "Application of NUREG/CR-5999 Interim Fatigue Curves to Selected Nuclear Power Plant Components," March 1995.
11. Letter from Ashok C. Thadani of the Office of Nuclear Regulatory Research to William D. Travers, Executive Director of Operations, dated December 26, 1999.
12. NUREG/CR-6674, "Fatigue Analysis of Components for 60-Year Plant Life," June 2000.
13. NUREG-1801, "Generic Aging Lessons Learned (GALL)," U.S. Nuclear Regulatory Commission, March 2001.
14. NUREG/CR-6583, "Effects of LWR Coolant Environments on Fatigue Design Curves of Carbon and Low-Alloy Steels," March 1998.
15. NUREG/CR-5704, "Effects of LWR Coolant Environments on Fatigue Design Curves of Austenitic Stainless Steels," April 1999.
Table 4.3-1. Stress Range Reduction Factors
| Number of Equivalent Full Temperature Cycles |
Stress Range Reduction Factor |
|---|---|
| 7,000 and less | 1.0 |
| 7,000 to 14,000 | 0.9 |
| 14,000 to 22,000 | 0.8 |
| 22,000 to 45,000 | 0.7 |
| 45,000 to 100,000 | 0.6 |
| 100,000 and over | 0.5 |
Table 4.3-2. Example of FSAR Supplement for Metal Fatigue TLAA Evaluation
10 CFR 54.21(c)(1)(iii) Example
| TLAA | Description of Evaluation |
Implementation Schedule* |
|---|---|---|
| Metal fatigue | The aging management program monitors and tracks the number of critical thermal and
pressure test transients, and
monitors the cycles for the selected reactor coolant system components. The aging management program will address the effects of the coolant environment on component fatigue life by assessing the impact of the reactor coolant environment on a sample of critical components that include, as a minimum, those components selected in NUREG/CR-6260. The sample of critical components can be evaluated by applying environmental correction factors to the existing ASME Code fatigue analyses. Formulas for calculating the environmental life correction factors are contained in NUREG/CR-6583 for carbon and low-alloy steels and in NUREG/CR-5704 for austenitic SSs. |
Evaluation should be completed before the period of extended operation |
| * An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date. | ||
4.4 Environmental Qualification (EQ) of Electric Equipment
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Review Responsibilities
Primary - Branch responsible for electrical engineering
Secondary - None
4.4.1 Areas of Review
The NRC has established nuclear station environmental qualification requirements in 10 CFR 50 Appendix A Criterion 4, and 10 CFR 50.49. 10 CFR 50.49 specifically requires that an environmental qualification program be established to demonstrate that certain electrical components located in "harsh" plant environments (that is, those areas of the plant that could be subject to the harsh environmental effects of a loss of coolant accident [LOCA], high energy line breaks [HELBs], or post-LOCA radiation) are qualified to perform their safety function in those harsh environments after the effects of in-service aging. 10 CFR 50.49 requires that the effects of significant aging mechanisms be addressed as part of environmental qualification. For the purpose of license renewal only those components with a qualified life of 40 years or greater would be TLAAs.
4.4.1.1 Time-Limited Aging Analysis
All operating plants must meet the requirements of 10 CFR 50.49 for certain important-to-safety electrical components. 10 CFR 50.49 defines the scope of components to be included, requires the preparation and maintenance of a list of in-scope components, and requires the preparation and maintenance of a qualification file that includes component performance specifications, electrical characteristics, and environmental conditions. 10 CFR 50.49(e)(5) contains provisions for aging that require, in part, consideration of all significant types of aging degradation that can affect component functional capability. 10 CFR 50.49(e) also requires component replacement or refurbishment prior to the end of designated life, unless additional life is established through ongoing qualification. 10 CFR 50.49(f) establishes four methods of demonstrating qualification for aging and accident conditions. 10 CFR 50.49(k) and (l) permit different qualification criteria to apply based on plant and component vintage. Supplemental environmental qualification regulatory guidance for compliance with these different qualification criteria is provided in RG 1.89, Rev. 1, "Environmental Qualification of Certain Electric Equipment Important to Safety for Nuclear Power Plants" (Ref. 1), the Division of Operating Reactors (DOR) Guidelines (Ref. 2), and NUREG-0588 (Ref. 3). The principal nuclear industry qualification standards for electric equipment are IEEE STD. 323-1971 (Ref. 4) and IEEE STD. 323-1974 (Ref. 5). These standards contain explicit environmental qualification considerations based on TLAAs. Compliance with 10 CFR 50.49 provides reasonable assurance that the component can perform its intended functions during accident conditions after experiencing the effects of in-service aging.
4.4.1.1.1 DOR Guidelines
The qualification of electric equipment that is subject to significant known degradation due to aging where a qualified life was previously established will be reviewed for the period of extended operation according to the requirements of Section 5.2.4 of the DOR Guidelines. If a qualified life was not previously established, the qualification will be reviewed to the requirements of section 7 of the DOR Guidelines.
4.4.1.1.2 NUREG-0588, CATEGORY II (IEEE STD. 323-1971)
The qualification of certain electric equipment important to safety that are subject to the requirements of NUREG-0588, Category II, will be reviewed to those requirements for the period of extended operation to assess the validity of the extended qualification. These requirements include IEEE STD. 382-1972 (Ref. 6) for valve operators, and IEEE STD. 334-1971 (Ref. 7.)
4.4.1.1.3 NUREG-0588, CATEGORY I (IEEE STD. 323-1974)
The qualification of certain electric equipment important to safety that are subject to the requirements of NUREG-0588, Category I, will be reviewed to those requirements for the period of extended operation to assess the validity of the extended qualification.
4.4.1.2 Generic Safety Issue
The NRC has decided that the adequacy of environmental qualification is a potential safety issue to be addressed by the current regulatory process for operating reactors (Refs. 8 and 9). GSI-168, "Environmental Qualification of Electrical Equipment," (Ref. 10) is being addressed separately under a generic task action plan (Refs. 11 and 12). Industry data on cables have been reviewed (Ref. 13). The staff continues to make progress in the cable research program, including the investigation of condition monitoring techniques to predict the condition and accident survivability of cables. GSI-168 is scheduled for resolution in March 2001.
An applicant's consideration of GSI-168 for license renewal is an area of review.
4.4.1.3 FSAR Supplement
The detailed information on the evaluation of TLAAs is contained in the renewal application. A summary description of the evaluation of TLAAs for the period of extended operation is contained in the applicant's FSAR supplement. The FSAR supplement is an area of review.
4.4.2 Acceptance Criteria
The acceptance criteria for the areas of review described in Subsection 4.4.1 of this review plan section delineate acceptable methods for meeting the requirements of the NRC's regulations in 10 CFR 54.21(c)(1).
4.4.2.1 Time-Limited Aging Analysis
Pursuant to 10 CFR 54.21(c)(1)(i) - (iii), an applicant must demonstrate one of the following:
(i) the analyses remain valid for the period of extended operation,
(ii) the analyses have been projected to the end of the extended period of operation, or
(iii) the effects of aging on the intended function(s) will be adequately managed for the period of extended operation.
Specific acceptance criteria for environmental qualification of certain electric equipment important to safety analyzed to Section 5.2.4 of the DOR Guidelines; NUREG-0588, Category II (Section 4); or NUREG-0588, Category I, depend on the applicant's choice, that is, 10 CFR 54.21(c)(1)(i), (ii), or (iii), are:
4.4.2.1.1 10 CFR 54.21(c)(1)(i)
The existing qualification is based on previous testing, analysis, or operating experience, or combinations thereof, that demonstrate that the equipment is qualified for the period of extended operation. For option (i), the aging evaluation existing at the time of the renewal application for the component remains valid for the period of extended operation, and no further evaluation is necessary.
4.4.2.1.2 10 CFR 54.21(c)(1)(ii)
Qualification of the equipment is extended for the period of extended operation by testing, analysis, or operating experience, or combinations thereof, in accordance with the CLB requirements. For option (ii), a reanalysis of the aging evaluation is performed in order to project the qualification of the component through the period of extended operation. Important reanalysis attributes of an aging evaluation include analytical methods, data collection and reduction methods, underlying assumptions, acceptance criteria, and corrective actions if acceptance criteria are not met. These reanalysis attributes are discussed in Table 4.4-1.
4.4.2.1.3 10 CFR 54.21(c)(1)(iii)
In Chapter X of the GALL report (Ref. 14), the staff has evaluated the environmental qualification program (10 CFR 50.49) and determined that it is an acceptable aging management program to address environmental qualification according to 10 CFR 54.21(c)(1)(iii). The GALL report may be referenced in a license renewal application, and should be treated in the same manner as an approved topical report. In referencing the GALL report, the applicant should indicate that the material referenced is applicable to the specific plant involved and should provide the information necessary to adopt the finding of program acceptability as described and evaluated in the report. The applicant should also verify that the approvals set forth in the GALL report for the generic program apply to the applicant's program.
4.4.2.2 Generic Safety Issue
One acceptable approach is to provide a technical rationale demonstrating that the CLB for environmental qualification will be maintained in the period of extended operation. (Ref. 15)
4.4.2.3 FSAR Supplement
The specific criterion for meeting 10 CFR 54.21(d) is:
The summary description of the evaluation of TLAAs for the period of extended operation in the FSAR supplement is appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the TLAA regarding the basis for determining that the applicant has made the demonstration required by 10 CFR 54.21(c)(1).
4.4.3 Review Procedures
For each area of review described in Subsection 4.4.1, the following review procedures should be followed:
4.4.3.1 Time-Limited Aging Analysis
For electric equipment qualified to the requirements of 10 CFR 50.49, the review procedures, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), are:
4.4.3.1.1 10 CFR 54.21(c)(1)(i)
The documented results, test data, analyses, etc., of the previous qualification, which consisted of an appropriate combination of testing, analysis, and operating experience, are reviewed to confirm that the original qualified life remains valid for the period of extended operation.
4.4.3.1.2 10 CFR 54.21(c)(1)(ii)
The results of projecting the qualification to the end of the period of extended operation will be reviewed. The qualification methods include testing, analysis, operating experience, or combinations thereof.
The reanalysis of an aging evaluation is normally performed to extend the qualification by reducing excess conservatisms incorporated in the prior evaluation. Such a reanalysis is performed on a routine basis as part of an environmental qualification program. A component life-limiting condition may be due to thermal, radiation, or cyclical aging; the vast majority of component aging limits are based on thermal conditions. Conservatisms may exist in aging evaluation parameters, such as the assumed ambient temperature of the component, unrealistically low activation energy, or in the application of a component (de-energized versus energized). The reanalysis of an aging evaluation is documented according to the plant's quality assurance program requirements, which requires the verification of assumptions and conclusions. For reanalysis, the reviewer verifies that an applicant has completed its reanalysis, addressing attributes of analytical methods, data collection and reduction methods, underlying assumptions, acceptance criteria, and corrective actions if acceptance criteria are not met (See Table 4.4-1). The reviewer also verifies that the reanalysis has been completed in a timely manner prior to the end of qualified life.
4.4.3.1.3 10 CFR 54.21 (c)(1)(iii)
The applicant may reference the GALL report in its license renewal application, as appropriate. The review should verify that the applicant has stated that the report is applicable to its plant with respect to its environmental qualification program. The reviewer verifies that the applicant has identified the appropriate program as described and evaluated in the GALL report. The reviewer also ensures that the applicant has stated that its environmental qualification program contains the same program elements that the staff evaluated and relied upon in approving the corresponding generic program in the GALL report. No further staff evaluation is necessary.
4.4.3.2 Generic Safety Issue
For license renewal, the Statements of Consideration (SOC) for the amended license renewal rule (60 FR 22484) provide four approaches that could be used to satisfy the finding required by 10 CFR 54.29. With respect to addressing GSI-168 for license renewal, until completion of an ongoing research program and staff evaluations, the potential issues associated with GSI-168 and their scope have not been defined to the point that a license renewal applicant can reasonably be expected to address them at this time. Therefore, an acceptable approach described in the SOC is to provide a technical rationale demonstrating that the current licensing basis for environmental qualification pursuant to 10 CFR 50.49 will be maintained in the period of extended operation. Although the SOC also indicates that an applicant should provide a brief description of one or more reasonable options that would be available to adequately manage the effects of aging, the reviewer should not expect an applicant to provide the options at this time. A renewal applicant should monitor updates to NUREG-0933, "A Prioritization of Generic Safety Issues," for revisions to GSI-168 during the review of its application, and should supplement its license renewal application if the issues associated with GSI-168 become defined such that providing the options or pursuing one of the other approaches described in the SOC becomes feasible (Ref. 15).
4.4.3.3 FSAR Supplement
The reviewer verifies that the applicant has provided information, to be included in the FSAR supplement that includes a summary description of the TLAA evaluation of the environmental qualification of electric equipment. Table 4.4-2 contains examples of acceptable FSAR supplement information for this TLAA. The reviewer verifies that the applicant has provided a FSAR supplement with information equivalent to that in Table 4.4-2. The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement, at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59. The staff will review any such changes when the next update is submitted.
As noted in Table 4.4-2, an applicant need not incorporate the implementation schedule into its FSAR. However, the review should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation.
The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
4.4.4 Evaluation of Findings
The reviewer verifies that the applicant has provided information sufficient to satisfy the provisions of this review plan section and that the staff's evaluation supports conclusions of the following type, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), to be included in the staff's safety evaluation report:
The staff concludes that the applicant has provided an acceptable demonstration, pursuant to 10 CFR 54.2 (c)(1), that, for the environmental qualification of Electric Equipment TLAA, [choose which is appropriate] (i) the analyses remain valid for the period of extended operation, (ii) the analyses have been projected to the end of the period of extended operation, or (iii) the effects of aging on the intended function(s) will be adequately managed for the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of the environmental qualification of electric equipment TLAA evaluation for the period of extended operation as reflected in the license condition.
4.4.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method for complying with specific portions of the NRC's regulations, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
4.4.6 References
1. Regulatory Guide 1.89, Rev. 1, "Environmental Qualification of Certain Electric Equipment Important to Safety for Nuclear Power Plants," June 1984.
2. "Guidelines for Evaluating Environmental Qualification of Class 1E Electrical Equipment in Operating Reactors," (DOR Guidelines), November 1979.
3. NUREG-0588, "Interim Staff Position on Environmental Qualification of Safety-Related Equipment," July 1981.
4. IEEE STD. 323-1971, "IEEE Trial Use Standard; General Guide for Qualifying Class 1E Equipment for Nuclear Power Generating Stations."
5. IEEE STD. 323-1974, "IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations."
6. IEEE STD. 382-1972, "Standard for Qualification of Actuators for Power Operated Valve Assemblies with Safety Related Functions for Nuclear Power Plants."
7. IEEE STD. 334-1971, "IEEE Standard for Type Tests of Continuous Duty Class 1E Motors for Nuclear Power Generating Stations."
8. SECY-93-049, "Implementation of 10 CFR Part 54, 'Requirements for Renewal of Operating Licenses for Nuclear Power Plants,'" March 1, 1993.
9. Staff Requirements Memorandum from Samuel J. Chilk, dated June 28, 1993.
10. NUREG-0933, "A Prioritization of Generic Safety Issues," Supplement 20, July 1996.
11. Letter from William T. Russell of NRC to William Rasin of the Nuclear Management and Resources Council, dated July 30, 1993.
12. Memorandum from James M. Taylor of NRC to the Commission, "Environmental Qualification of Electric Equipment," dated April 8, 1994.
13. NUREG/CR-6384, Volumes 1 and 2, "Literature Review of Environmental Qualification of Safety-Related Electric Cables," April 1996.
14. NUREG-1801, "Generic Aging Lessons Learned (GALL)," U.S. Nuclear Regulatory Commission, July 2001.
15. Letter from Christopher I. Grimes (NRC) to Doug Walters (NEI), "Guidance on addressing GSI-168 for license renewal", dated June 2, 1998.
Table 4.4-1. Environmental Qualification Reanalysis Attributes
| Reanalysis Attributes | Description |
|---|---|
| Analytical methods | The analytical models used in the reanalysis of an aging evaluation should be the same as those previously applied during the prior evaluation. The Arrhenius methodology is an acceptable thermal model for performing a thermal aging evaluation. The analytical method used for a radiation aging evaluation is to demonstrate qualification for the total integrated dose (that is, normal radiation dose for the projected installed life plus accident radiation dose). For license renewal, one acceptable method of establishing the 60-year normal radiation dose is to multiply the 40 year normal radiation dose by 1.5 (that is, 60 years/40 years). The result is added to the accident radiation dose to obtain the total integrated dose for the component. For cyclical aging, a similar approach may be used. Other models may be justified on a case-by-case basis. |
| Data collection and reduction methods | Reducing excess conservatisms in the component service conditions (for example, temperature, radiation, cycles) used in the prior aging evaluation is the chief method used for a reanalysis. Temperature data used in an aging evaluation should be conservative and based on plant design temperatures or on actual plant temperature data. When used, plant temperature data can be obtained in several ways, including monitors used for technical specification compliance, other installed monitors, measurements made by plant operators during rounds, and temperature sensors on large motors (while the motor is not running). A representative number of temperature measurements are conservatively evaluated to establish the temperatures used in an aging evaluation. Plant temperature data may be used in an aging evaluation in different ways, such as (a) directly applying the plant temperature data in the evaluation, or (b) using the plant temperature data to demonstrate conservatism when using plant design temperatures for an evaluation. Any changes to material activation energy values as part of a reanalysis should be justified. Similar methods of reducing excess conservatisms in the component service conditions used in prior aging evaluations can be used for radiation and cyclical aging. |
| Underlying assumptions | environmental qualification component aging evaluations contain sufficient conservatisms to account for most environmental changes occurring due to plant modifications and events. When unexpected adverse conditions are identified during operational or maintenance activities that affect the environment of a qualified component, the affected environmental qualification component is evaluated, and appropriate corrective actions are taken, which may include changes to the qualification bases and conclusions. |
| Acceptance criteria and corrective actions | The reanalysis of an aging evaluation should extend the qualification of the component. If the qualification cannot be extended by reanalysis, the component must be refurbished, replaced, or requalified prior to exceeding the current qualification. A reanalysis should be performed in a timely manner (such that sufficient time is available to refurbish, replace, or requalify the component if the reanalysis is unsuccessful). |
Table 4.4-2. Examples of FSAR Supplement for Environmental Qualification of Electric Equipment TLAA Evaluation 10 CFR 54.21(c)(1)(i) Example
| TLAA | Description of Evaluation | Implementation Schedule* |
|---|---|---|
| Environmental qualification of electric equipment | The original environmental qualification qualified life has been shown to remain valid for the period of extended operation. | Completed |
10 CFR 54.21(c)(1)(ii) Example
| TLAA | Description of Evaluation | Implementation Schedule* |
|---|---|---|
| Environmental qualification of electric equipment | The environmental qualification has been projected to the end of the period of extended operation. Reanalysis addresses attributes of analytical methods, data collection and reduction methods, underlying assumptions, acceptance criteria, and corrective actions. | Completed |
10 CFR 54.21(c)(1)(iii) Example
| TLAA | Description of Evaluation | Implementation Schedule* |
|---|---|---|
| Environmental qualification of electric equipment | The existing environmental qualification process, in accordance with 10 CFR 50.49, will adequately manage aging of environmental qualification equipment for the period of extended operation because equipment will be replaced prior to reaching the end of its qualified life. Reanalysis addresses attributes of analytical methods, data collection and reduction methods, underlying assumptions, acceptance criteria, corrective actions if acceptance criteria are not met, and the period of time prior to the end of qualified life when the reanalysis will be completed. | Existing program |
| * An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date. | ||
4.5 Concrete Containment Tendon Prestress Analysis
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Review Responsibilities
Primary - Branch responsible for structural engineering
Secondary - None
4.5.1 Areas of Review
The prestressing tendons in prestressed concrete containments lose their prestressing forces with time due to creep and shrinkage of concrete, and relaxation of the prestressing steel. During the design phase, engineers estimate these losses to arrive at the end of operating life (Refs. 1 and 2), normally forty years. The operating experiences with the trend of prestressing forces indicate that the prestressing tendons lose their prestressing forces at a rate higher than predicted due to sustained high temperature (Ref. 3). Thus, it is necessary to perform TLAAs for the extended period of operation.
The adequacy of the prestressing forces in prestressed concrete containments is reviewed for the period of extended operation.
4.5.2 Acceptance Criteria
The acceptance criteria for the area of review described in Subsection 4.5.1 of this review plan section delineate acceptable methods for meeting the requirements of the NRC's regulations in 10 CFR 54.21(c)(1).
4.5.2.1 Time-Limited Aging Analysis
Pursuant to 10 CFR 54.21(c)(1)(i) - (iii), an applicant must demonstrate one of the following:
(i) The analyses remain valid for the period of extended operation;
(ii) The analyses have been projected to the end of the extended period of operation; or
(iii) The effects of aging on the intended function(s) will be adequately managed for the period of extended operation.
Accordingly, the specific options for satisfying the acceptance criterion are:
4.5.2.1.1 10 CFR 54.21(c)(1)(i)
The existing prestressing force evaluation remains valid because (1) losses of the prestressing force are less than the predicted losses as evidenced from the trend lines constructed from the recent inspection, (2) the period of evaluation covers the period of extended operation, and (3) the trend lines of the measured prestressing forces remain above the predicted lower limit (PLL) for each group of tendons for the period of extended operation.
4.5.2.1.2 10 CFR 54.21(c)(1)(ii)
The predicted lower limits (PLLs) of prestressing forces for each group of tendons developed for 40 years of operation should be extended to 60 years. The applicant should demonstrate that the trend lines of the measured prestressing forces will stay above the PLLs and the design Minimum Required Value (MRV) in the CLB for each group of tendons during the period of extended operation (Ref. 4). If this cannot be done, the applicant should develop a systematic plan for retensioning selected tendons so that the trend lines will remain above the PLLs for each group of tendons during the period of extended operation, or perform a reanalysis of containment to demonstrate design adequacy.
4.5.2.1.3 10 CFR 54.21(c)(1)(iii)
In Chapter X of the GALL report (Ref. 4), the staff has evaluated a program that assesses the concrete containment tendon prestressing forces, and has determined that it is an acceptable aging management program to address concrete containment tendon prestress according to 10 CFR 54.21(c)(1)(iii), except for operating experience. The GALL report recommends further evaluation of the applicant's operating experience related to the containment prestress force.
The GALL report may be referenced in a license renewal application, and should be treated in the same manner as an approved topical report. In referencing the GALL report, an applicant should indicate that the material referenced is applicable to the specific plant involved and should provide the information necessary to adopt the finding of program acceptability as described and evaluated in the report. An applicant should also verify that the approvals set forth in the GALL report for the generic program apply to the applicant's program.
4.5.2.2 FSAR Supplement
The specific criterion for meeting 10 CFR 54.21(d) is:
The summary description of the evaluation of TLAAs for the period of extended operation in the FSAR supplement is appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the TLAAs regarding the basis for determining that the applicant has made the demonstration required by 10 CFR 54.21(c)(1).
4.5.3 Review Procedures
For each area of review described in Subsection 4.5.1 of this review plan section, the following review procedures should be followed:
4.5.3.1 Time-Limited Aging Analysis
For a concrete containment prestressing tendon system, the review procedures, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), are:
4.5.3.1.1 10 CFR 54.21(c)(1)(i)
The results of a recent inspection to measure the amount of prestress loss are reviewed to ensure that the reduction of prestressing force is less than the predicted loss in the existing analysis. The reviewer verifies that the trend line of the measured prestressing force when plotted on the predicted prestressing force curve shows that the existing analysis will cover the period of extended operation.
4.5.3.1.2 10 CFR 54.21(c)(1)(ii)
The reviewer reviews the trend lines of the measured prestressing forces to ensure that individual tendon lift-off forces (rather than average lift-off forces of the tendon group) are considered in the regression analysis, as discussed in IN 99-10 (Ref. 3). Either the reviewer verifies that the trend lines will stay above the PLL prestressing forces for each group of tendons during the period of extended operation or, if the trend lines fall below the PLL during this period, the reviewer verifies that the applicant has a systematic plan for retensioning the tendons to ensure that the trend lines will return to being, and remain, above the PLL for each group of tendons during the period of extended operation. If the applicant chooses to reanalyze the containment, the reviewer verifies that the design adequacy is maintained in the period of extended operation.
4.5.3.1.3 10 CFR 54.21(c)(1)(iii)
An applicant may reference the GALL report in its license renewal application, as appropriate. The review should verify that the applicant has stated that the report is applicable to its plant with respect to its program that assesses the concrete containment tendon prestressing forces. The reviewer verifies that the applicant has identified the appropriate program as described and evaluated in the GALL report. The reviewer also ensures that the applicant has stated that its program contains the same program elements that the staff evaluated and relied upon in approving the corresponding generic program in the GALL report.
The GALL report recommends further evaluation of the applicant's operating experience related to the containment prestress force. The applicant's program should incorporate the relevant operating experience that occurred at the applicant's plant as well as at other plants. The applicant should consider applicable portions of the experience with prestressing systems described in Information Notice 99-10 (Ref. 3). Tendon operating experience could vary among plants with prestressed concrete containments. The difference could be due to the prestressing system design (for example, button-heads, wedge or swaged anchorages), environment, or type of reactor (PWR or BWR). The reviewer reviews the applicant's program to verify that the applicant has adequately considered plant-specific operating experience.
4.5.3.2 FSAR Supplement
The reviewer verifies that the applicant has provided information, to be included in the FSAR supplement, that includes a summary description of the evaluation of tendon prestress TLAA. Table 4.5-1 of this review plan section contains examples of acceptable FSAR supplement information for this TLAA. The reviewer verifies that the applicant has provided a FSAR supplement with information equivalent to that in Table 4.5-1.
The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Table 4.5-1, an applicant need not incorporate the implementation schedule into its FSAR. However, the review should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
4.5.4 Evaluation Findings
The reviewer verifies that the applicant has provided sufficient information to satisfy the provisions of this review plan section and that the staff's evaluation supports conclusions of the following type, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), to be included in the staff's safety evaluation report:
The staff concludes that the applicant has provided an acceptable demonstration, pursuant to 10 CFR 54.21(c)(1), that, for the concrete containment tendon prestress TLAA, [choose which is appropriate] (i) the analyses remain valid for the period of extended operation, (ii) the analyses have been projected to the end of the period of extended operation, or (iii) the effects of aging on the intended function(s) will be adequately managed for the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate description of the concrete containment tendon prestress TLAA evaluation for the period of extended operation as reflected in the license condition.
4.5.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
4.5.6 References
1. Regulatory Guide 1.35, Rev. 3, "Inspection of Ungrouted Tendons in Prestressed Concrete Containments," July 1990.
2. Regulatory Guide 1.35.1, "Determining Prestressing Forces for Inspection of Prestressed Concrete Containments," July 1990.
3. NRC Information Notice 99-10, "Degradation of Prestressing Tendon Systems in Prestressed Concrete Containments," April 1999.
4. NUREG-1801, "Generic Aging Lessons Learned (GALL)," U.S. Nuclear Regulatory Commission, July 2001.
Table 4.5-1. Examples of FSAR Supplement for Concrete Containment Tendon Prestress TLAA Evaluation
10 CFR 54.21(c)(1)(i) Example
| TLAA | Description of Evaluation | Implementation Schedule* |
|---|---|---|
| Concrete containment tendon prestress | The prestressing tendons are used to impart compressive forces in the prestressed concrete containments to resist the internal pressure inside the containment that would be generated in the event of a LOCA. The prestressing forces generated by the tendons diminish over time due to losses in prestressing forces in the tendons and in the surrounding concrete. The prestressing force evaluation has been determined to remain valid to the end of the period of extended operation, and the trend lines of the measured prestressing forces will stay above the PLLs for each group of tendons to the end of this period. | Completed |
10 CFR 54.21(c)(1)(ii) Example
| TLAA | Description of Evaluation | Implementation Schedule* |
|---|---|---|
| Concrete containment tendon prestress |
The prestressing tendons are used to impart compressive forces in the prestressed concrete containments to resist the internal pressure inside the containment that would be generated in the event of a LOCA. The prestressing forces generated by the tendons diminish over time due to losses in prestressing forces in the tendons and in the surrounding concrete. The prestressing forces have been reevaluated, showing that the trend lines of the measured prestressing forces will stay above the PLLs for each group of tendons to the end of the period of extended operation. | Completed |
10 CFR 54.21(c)(1)(iii) Example
| TLAA | Description of Evaluation | Implementation Schedule* |
|---|---|---|
| Concrete containment tendon prestress |
The prestressing tendons are used to impart compressive forces in the prestressed concrete containments to resist the internal pressure inside the containment that would be generated in the event of a LOCA. The prestressing forces generated by the tendons diminish over time due to losses of prestressing forces in the tendons and in the surrounding concrete. The aging management program developed to monitor the prestressing forces should ensure that, during each inspection, the trend lines of the measured prestressing forces show that they meet the requirements of 10 CFR 50.55a(b)(2)(ix)(B). If the trend lines cross the PLLs, corrective actions will be taken. The program will also incorporate any plant-specific and industry operating experience. | Program should be implemented before the period of extended operation. |
| * An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date. | ||
4.6 Containment Liner Plate, Metal Containments, and Penetrations Fatigue Analysis
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Review Responsibilities
Primary - Branch responsible for structural engineering
Secondary - Branch responsible for mechanical engineering
4.6.1 Areas of Review
The interior surface of a concrete containment structure is lined with thin metallic plates to provide a leak-tight barrier against the uncontrolled release of radioactivity to the environment, as required by 10 CFR Part 50. The thickness of the liner plates is generally between 1/4 in. (6.2 mm) and 3/8 in. (9.5 mm). The liner plates are attached to the concrete containment wall by stud anchors or structural rolled shapes or both. The design process assumes that the liner plates do not carry loads. However, normal loads, such as from concrete shrinkage, creep, and thermal changes, imposed on the concrete containment structure, are transferred to the liner plates through the anchorage system. Internal pressure and temperature loads are directly applied to the liner plates. Thus, under design-base conditions, the liner plates could experience significant strains. Some plants may have metal containments instead of concrete containments with liner plates.
Fatigue of the liner plates or metal containments may be considered in the design based on an assumed number of loading cycles for the current operating term. The cyclic loads include reactor building interior temperature variation during the heatup and cooldown of the reactor coolant system, a LOCA, annual outdoor temperature variations, thermal loads due to the high energy containment penetration piping lines (such as steam and feedwater lines), seismic loads, and pressurization due to periodic Type A integrated leak rate tests.
High energy piping penetrations and the fuel transfer canal in some plants are equipped with bellow assemblies. These are designed to accommodate relative movements between the containment wall (including the liner) and the adjoining structures. The penetrations have sleeves (up to 10 feet in length, with a 2 to 3-inch annulus around the piping) to penetrate the concrete containment wall and allow movement of the piping system. Dissimilar metal welds connect the piping penetrations to the bellows to provide leak-tight penetrations.
The containment liner plates, metal containments, penetration sleeves (including dissimilar metal welds), and penetration bellows may be designed in accordance with requirements of Section III of the ASME Boiler and Pressure Vessel Code. If a plant's code of record requires a fatigue analysis, then this analysis may be a TLAA and must be evaluated in accordance with 10 CFR 54.21(c)(1) to ensure that the effects of aging on the intended functions will be adequately managed for the period of extended operation.
The adequacy of the fatigue analyses of the containment liner plates (including welded joints), metal containments, penetration sleeves, dissimilar metal welds, and penetration bellows is reviewed in this review plan section for the period of extended operation. The fatigue analyses of the pressure boundary of process piping are reviewed separately following the guidance in Section 4.3, "Metal Fatigue," of this review plan.
4.6.1.1 Time-Limited Aging Analysis
The containment liner plates (including welded joints), metal containments, penetration sleeves, dissimilar metal welds, and penetration bellows may be designed and/or analyzed in accordance with ASME code requirements. The ASME code contains explicit metal fatigue or cyclic considerations based on TLAAs. Specific requirements are contained in the design code of reference for each plant.
4.6.1.1.1 ASME Section III, MC or Class 1
ASME Section III Division 2, "Code for Concrete Reactor Vessel and Containments," Subsection CC, "Concrete Containment," and Division 1, Subsection NE, "Class MC Components," (Ref. 1) require a fatigue analysis for liner plates, metal containments, and penetrations that considers all cyclic loads based on the anticipated number of cycles. Containment components may also be designed to ASME Section III Class 1 requirements. A Section III, MC or Class 1 fatigue analysis requires the calculation of the CUF based on the fatigue properties of the materials and the expected fatigue service of the component. The ASME code limits the CUF to a value less than one for acceptable fatigue design. The fatigue resistance of the liner plates or metal containments, and penetrations during the period of extended operation is an area of review.
4.6.1.1.2 Other Evaluations Based on CUF
Other evaluations also contain metal fatigue analysis requirements based on a CUF calculation, such as metal bellows designed to ASME NC-3649.4(e)(3) or NE-3366.2(e)(3). For these cases, the discussion relating to ASME Section III, MC or Class 1, in Subsection 4.6.1.1.1 of this review plan section, applies.
4.6.1.2 FSAR Supplement
Detailed information on the evaluation of TLAAs is contained in the renewal application. A summary description of the evaluation of TLAAs for the period of extended operation is contained in the applicant's FSAR supplement. The FSAR supplement is an area of review.
4.6.2 Acceptance Criteria
The acceptance criteria for the areas of review described in Subsection 4.6.1 of this review plan section delineate acceptable methods for meeting the requirements of the NRC's regulations in 10 CFR 54.21(c)(1).
4.6.2.1 Time-Limited Aging Analysis
Pursuant to 10 CFR 54.21(c)(1), an applicant must demonstrate one of the following:
(i) The analyses remain valid for the period of extended operation;
(ii) The analyses have been projected to the end of the extended period of operation; or
(iii) The effects of aging on the intended function(s) will be adequately managed for the period of extended operation.
Specific acceptance criteria for fatigue of containment liner plates, metal containments, liner plate weld joints, dissimilar metal welds, penetration sleeves, and penetration bellows are:
4.6.2.1.1 ASME Section III, MC or Class 1
For containment liner plates, metal containments, and penetrations designed or analyzed to ASME MC or Class 1 requirements, the acceptance criteria, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), are:
4.6.2.1.1.1 10 CFR 54.21(c)(1)(i)
The existing CUF calculations remain valid because the number of assumed cyclic loads will not be exceeded during the period of extended operation.
4.6.2.1.1.2 10 CFR 54.21(c)(1)(ii)
CLB fatigue analysis, per ASME Code Section III, was conducted for a 40-year life. The CUF calculations should be reevaluated based on an increased number of assumed cyclic loads to cover the period of extended operation. All cyclic loads considered in the original fatigue analyses (including Type A and Type B leak rate tests) should be reevaluated and revised as necessary. The revised analysis should show that the CUF will not exceed one, as required by the ASME code, during the period of extended operation.
4.6.2.1.1.3 10 CFR 54.21(c)(1)(iii)
The effects of aging on the intended function(s) will be adequately managed for the period of extended operation. The component could be replaced; the CUF for the replacement must be less than one during the period of extended operation.
An alternative aging management program provided by the applicant will be evaluated on a case-by-case basis to ensure that the aging effects will be managed such that the intended functions(s) will be maintained during the period of extended operation. In cases where a mitigation or inspection program is proposed, the aging management program may be evaluated against the 10 elements described in Branch Technical Position RLSB-1 (Appendix A.1 of this standard review plan).
4.6.2.1.2 Other Evaluations Based on CUF
The acceptance criteria in Subsection 4.6.2.1.2 of this review plan section apply.
4.6.2.2 FSAR Supplement
The specific criterion for meeting 10 CFR 54.21(d) is:
The summary description of the evaluation of TLAAs for the period of extended operation in the FSAR supplement is appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the TLAAs regarding the basis for determining that the applicant has made the demonstration required by 10 CFR 54.21(c)(1).
4.6.3 Review Procedures
For each area of review described in Subsection 4.6.1 of this review plan section, the following review procedures should be followed:
4.6.3.1 Time-Limited Aging Analysis
4.6.3.1.1 ASME Section III, MC or Class 1
For containment liner plates, metal containments, and penetrations designed or analyzed to ASME MC or Class 1 requirements, the review procedures, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), are:
4.6.3.1.1.1 10 CFR 54.2l(c)(1)(i)
The number of assumed transients used in the existing CUF calculations for the current operating term is compared to the extrapolation to 60 years of operation of the number of operating transients experienced to date. The comparison confirms that the number of transients in the existing analyses will not be exceeded during the period of extended operation.
4.6.3.1.1.2 10 CFR 54.21(c)(1)(ii)
Operating transient experience and a list of the increased number of assumed cyclic loads projected to the end of the period of extended operation are reviewed to ensure that the cyclic load projection is adequate. The revised CUF calculations based on the projected number of assumed cyclic loads are reviewed to ensure that the CUF remains less than one at the end of the period of extended operation.
The code of record should be used for the reevaluation, or the applicant may update to a later code edition pursuant to 10 CFR 50.55a. In the latter case, the reviewer verifies that the requirements in 10 CFR 50.55a are met.
4.6.3.1.1.3 10 CFR 54.21(c)(1)(iii)
The applicant's proposed aging management program to ensure that the effects of aging on the intended function(s) will be adequately managed for the period of extended operation is reviewed. If the applicant proposed a component replacement before its CUF exceeds one, the reviewer verifies that the CUF for the replacement will remain less than one during the period of extended operation.
Other applicant proposed programs will be reviewed on a case-by-case basis.
4.6.3.1.2 Other Evaluations Based on CUF
The review procedures in Subsection 4.6.3.1 of this review plan section apply.
4.6.3.2 FSAR Supplement
The reviewer verifies that the applicant has provided information, to be included in the FSAR supplement, that includes a summary description of the evaluation of containment liner plate, metal containments, and penetrations fatigue TLAA. Table 4.6-1 of this review plan section contains examples of acceptable FSAR supplement information for this TLAA. The reviewer verifies that the applicant has provided a FSAR supplement with information equivalent to that in Table 4.6-1.
The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Table 4.6-1, the applicant need not incorporate the implementation schedule into its FSAR. However, the review should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
4.6.4 Evaluation Findings
The reviewer verifies that the applicant has provided sufficient information to satisfy the provisions of this review plan section and that the staff's evaluation supports conclusions of the following type, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), to be included in the staff's safety evaluation report:
The staff evaluation concludes that the applicant has provided an acceptable demonstration, pursuant to 10 CFR 54.21(c)(1), that, for the containment liner plate or metal containment, and penetrations fatigue TLAA, [choose which is appropriate] (i) the analyses remain valid for the period of extended operation, (ii) the analyses have been projected to the end of the period of extended operation, or (iii) the effects of aging on the intended function(s) will be adequately managed for the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of the containment liner plate or metal containment, and penetrations fatigue TLAA evaluation for the period of extended operation as reflected in the license condition.
4.6.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
4.6.6 References
1. ASME Boiler and Pressure Vessel Code, Section III, Division 2, "Code for Concrete Reactor Vessels and Containments," Subsection CC, "Concrete Containment," and Division 1, Subsection NE, "MC Components," American Society of Mechanical Engineers, New York, New York, 1989 or other editions as approved in 10 CFR 50.55a.
Table 4.6-1. Examples of FSAR Supplement for Containment Liner Plates, Metal Containments, and Penetrations Fatigue TLAA Evaluation
10 CFR 54.21(c)(1)(i) Example
| TLAA | Description of Evaluation | Implementation Schedule* |
|---|---|---|
| Containment liner
plates (or metal containment) and penetrations fatigue |
The containment liner plates (or metal containment), liner weld joints, penetration sleeves, dissimilar metal welds, and penetration bellows provide a leak-tight barrier. A Section III, MC or Class 1 fatigue analysis limits the CUF to a value less than one for acceptable fatigue design. The existing CUF evaluation has been determined to remain valid because the number of assumed cyclic loads would not be exceeded during the period of extended operation. | Completed |
10 CFR 54.21(c)(1)(ii) Example
| TLAA | Description of Evaluation | Implementation Schedule* |
|---|---|---|
| Containment liner
plates (or metal containment) and penetrations fatigue |
The containment liner plates (or metal containment), liner weld joints, penetration sleeves, dissimilar metal welds, and penetration bellows provide a leak-tight barrier. A Section III, MC or Class 1 fatigue analysis limits the CUF to a value less than one for acceptable fatigue design. The CUF calculations have been reevaluated based on an increased number of assumed cyclic loads to cover the period of extended operation. The revised CUF will not exceed one during the period of extended operation. | Completed |
10 CFR 54.21(c)(1)(iii) Example
| TLAA | Description of Evaluation | Implementation Schedule* |
|---|---|---|
| Containment liner
plates (or metal containment) and penetrations fatigue |
The containment liner plates (or metal containment), liner weld joints, penetration sleeves, dissimilar metal welds, and penetration bellows provide a leak-tight barrier. A Section III, MC or Class 1 fatigue analysis limits the CUF to a value less than one for acceptable fatigue design. If the component is replaced, the CUF for the replacement will be shown to be less than one during the period of extended operation. | Program should be implemented before the period of extended operation. |
| Note: All containment components
need not meet the same requirement. It is likely that the liner plate and the bellows may be
evaluated per
10CFR54.21(c)(1)(i), while high energy penetrations may be evaluated per
10CFR54.21(c)(1)(ii).
* An applicant need not incorporate the implementation schedule into its FSAR. However, the reviewer should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation. The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date. | ||
4.7 Other Plant-specific Time-limited Aging Analyses
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Review Responsibilities
Primary - Branch responsible for engineering
Secondary - Other branches responsible for systems, as appropriate
4.7.1 Areas of Review
There are certain plant-specific safety analyses that may have been based on an explicitly assumed 40-year plant life (for example, aspects of the reactor vessel design) and may, therefore, be time-limited aging analyses (TLAAs.) Pursuant to 10 CFR 54.21(c), a license renewal applicant is required to evaluate TLAAs. The definition of TLAAs is provided in 10 CFR 54.3 and in Section 4.1 of this standard review plan.
TLAAs may have evolved since issuance of a plant's operating license, and are plant-specific. As indicated in 10 CFR 54.30, the adequacy of the plant's CLB, which includes TLAAs, is not an area within the scope of the license renewal review. Any question regarding the adequacy of the CLB must be addressed under the backfit rule (10 CFR 50.109) and is separate from the license renewal process.
License renewal reviews focus on the period of extended operation. Pursuant to 10 CFR 54.30, if the reviews required by 10 CFR 54.21(a) or (c) show that there is not reasonable assurance during the current license term that licensed activities will be conducted in accordance with the CLB, the licensee is required to take measures under its current license to ensure that the intended function of those systems, structures, or components will be maintained in accordance with the CLB throughout the term of the current license. The adequacy of the measures for the term of the current license is not within the scope of the license renewal review.
Pursuant to 10 CFR 54.21(c), an applicant must provide a listing of TLAAs and plant-specific exemptions that are based on TLAAs. The staff reviews the applicant's identification of TLAAs and exemptions separately, following the guidance in Section 4.1 of this standard review plan.
Based on lessons learned in the review of the initial license renewal applications, the staff has developed review procedures for the evaluation of certain TLAAs. If an applicant identifies these TLAAs as applicable to its plant, the staff reviews them separately, following the guidance in Sections 4.2 through 4.6. The staff reviews other TLAAs that are identified by the applicant, following the generic guidance in this review plan section. For particular systems, the staff from branches responsible for those systems may be requested to assist in the review, as appropriate.
The following areas relating to a TLAA are reviewed:
4.7.1.1 Time-Limited Aging Analysis
The evaluation of the TLAA for the period of extended operation is reviewed.
4.7.1.2 FSAR Supplement
The FSAR supplement summarizing the evaluation of the TLAA for the period of extended operation in accordance with 10 CFR 54.21(d) is reviewed.
4.7.2 Acceptance Criteria
The acceptance criteria for the areas of review described in Subsection 4.7.1 of this review plan section delineate acceptable methods for meeting the requirements of the NRC's regulations in 10 CFR 54.21(c)(1).
4.7.2.1 Time-Limited Aging Analysis
Pursuant to 10 CFR 54.21(c)(1)(i) - (iii), an applicant must demonstrate one of the following for the TLAAs:
(i) The analyses remain valid for the period of extended operation;
(ii) The analyses have been projected to the end of the extended period of operation; or
(iii) The effects of aging on the intended function(s) will be adequately managed for the period of extended operation.
4.7.2.2 FSAR Supplement
The specific criterion for meeting 10 CFR 54.21(d) is:
The summary description of the evaluation of TLAAs for the period of extended operation in the FSAR supplement is appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information associated with the TLAAs regarding the basis for determining that the applicant has made the demonstration required by 10 CFR 54.21 (c)(1).
4.7.3 Review Procedures
The requirement for evaluation of TLAAs captures, for review of applications for license renewal, certain plant-specific aging analyses that are explicitly based on the duration of the current operating license of the plant. The concern is that these aging analyses do not cover the period of extended operation. Unless these analyses are evaluated, there is no assurance that the systems, structures, and components addressed by these analyses can perform their intended function(s) during the period of extended operation.
For each area of review described in Subsection 4.7.1 of this review plan section, the following review procedures are followed:
4.7.3.1 Time-Limited Aging Analysis
For each TLAA identified, the review procedures depend on the applicant's choice of methods of compliance from those identified in 10 CFR 54.21(c)(1)(i), (ii), or (iii), as follows:
4.7.3.1.1 10 CFR 54.21(c)(1)(i)
Justification provided by the applicant is reviewed to verify that the existing analyses are valid for the period of extended operation. The existing analyses should be shown to be bounding even during the period of extended operation.
The applicant should describe the TLAA with respect to the objectives of the analysis, assumptions used in the analysis, conditions, acceptance criteria, relevant aging effects, and intended function(s). The applicant should show that (1) conditions and assumptions used in the analysis already address the relevant aging effects for the period of extended operation, and (2) acceptance criteria are maintained to provide reasonable assurance that the intended function(s) is maintained for renewal. Thus, no reanalysis is necessary for renewal.
In some instances, the applicant may identify activities to be performed to verify the assumption basis of the calculation, such as cycle counting. An evaluation of that activity should be provided by the applicant. The reviewer should assure that the applicant's activity is sufficient to confirm the calculation assumptions for the 60-year period.
If the TLAA must be modified or recalculated to extend the period of evaluation to consider the period of extended operation, the reevaluation should be addressed under 10 CFR 54.21(c)(1)(ii).
4.7.3.1.2 10 CFR 54.21(c)(1)(ii)
The documented results of the revised analyses are reviewed to verify that their period of evaluation is extended such that they are valid for the period of extended operation, for example, 60 years. The applicable analysis technique can be the one that is in effect in the plant's CLB at the time of filing of the renewal application.
The applicant may recalculate the TLAA using a 60-year period to show that the TLAA acceptance criteria continue to be satisfied for the period of extended operation. The applicant may also revise the TLAA by recognizing and reevaluating any overly conservative conditions and assumptions. Examples include relaxing overly conservative assumptions in the original analysis, using new or refined analytical techniques, and performing the analysis using a 60-year period. The applicant shall provide a sufficient description of the analysis and document the results of the reanalysis to show that it is satisfactory for the 60-year period.
As applicable, the plant's code of record should be used for the reevaluation, or the applicant may update to a later code edition pursuant to 10 CFR 50.55a. In the latter case, the reviewer verifies that the requirements in 10 CFR 50.55a are met.
In some cases, the applicant may identify activities to be performed to verify the assumption basis of the calculation, such as cycle counting. An evaluation of that activity should be provided by the applicant. The reviewer should assure that the applicant's activity is sufficient to confirm the calculation assumptions for the 60-year period.
4.7.3.1.3 10 CFR 54.21(c)(1)(iii)
Under this option, the applicant would propose to manage the aging effects associated with the TLAA by an aging management program in the same manner as would be described in the IPA in 10 CFR 54.21(a)(3). The reviewer reviews the applicant's aging management program to verify that the effects of aging on the intended function(s) will be adequately managed consistent with the CLB for the period of extended operation.
The applicant should identify the structures and components associated with the TLAA. The TLAA should be described with respect to the objectives of the analysis, conditions, assumptions used, acceptance criteria, relevant aging effects, and intended function(s). In cases where a mitigation or inspection program is proposed, the reviewer may use the guidance provided in Branch Technical Position RLSB-1 of this standard review plan to ensure that the effects of aging on the structure and component intended function(s) are adequately managed for the period of extended operation.
4.7.3.2 FSAR Supplement
The reviewer verifies that the applicant has provided information, to be included in the FSAR supplement, that includes a summary description of the evaluation of each TLAA. Each such summary description is reviewed to verify that it is appropriate such that later changes can be controlled by 10 CFR 50.59. The description should contain information that the TLAAs have been dispositioned for the period of extended operation. Sections 4.2 through 4.6 of this standard review plan contain examples of acceptable FSAR supplement information for TLAA evaluation.
The staff expects to impose a license condition on any renewed license to require the applicant to update its FSAR to include this FSAR supplement at the next update required pursuant to 10 CFR 50.71(e)(4). As part of the license condition, until the FSAR update is complete, the applicant may make changes to the programs described in its FSAR supplement without prior NRC approval, provided that the applicant evaluates each such change pursuant to the criteria set forth in 10 CFR 50.59.
As noted in Sections 4.2 through 4.6, an applicant need not incorporate the implementation schedule into its FSAR. However, the review should verify that the applicant has identified and committed in the license renewal application to any future aging management activities to be completed before the period of extended operation.
The staff expects to impose a license condition on any renewed license to ensure that the applicant will complete these activities no later than the committed date.
4.7.4 Evaluation Findings
The reviewer verifies that the applicant has provided sufficient information to satisfy the provisions of this review plan section and that the staff's evaluation supports conclusions of the following type, depending on the applicant's choice of 10 CFR 54.21(c)(1)(i), (ii), or (iii), to be included in the staff's safety evaluation report:
The staff concludes that the applicant has provided an acceptable demonstration, pursuant to 10 CFR 54.21(c)(1), that, for the (name of specific) TLAA, [choose which is appropriate] (i) the analyses remain valid for the period of extended operation, (ii) the analyses have been projected to the end of the period of extended operation, or (iii) the effects of aging on the intended function(s) will be adequately managed for the period of extended operation. The staff also concludes that the FSAR supplement contains an appropriate summary description of this TLAA evaluation for the period of extended operation as reflected in the license condition.
4.7.5 Implementation
Except in those cases in which the applicant proposes an acceptable alternative method, the method described herein will be used by the staff in its evaluation of conformance with NRC regulations.
4.7.6 References
None
Appendix A: Branch Technical Positions
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A.1 Aging Management Review -- Generic
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A.1.1 Background
Pursuant to 10 CFR 54.21(a)(3), a license renewal applicant is required to demonstrate that the effects of aging on structures and components subject to an Aging Management Review (AMR) will be adequately managed so that their intended functions will be maintained consistent with the CLB for the period of extended operation. The purpose of this branch technical position (RLSB-1) is to address the aging management demonstration that has not been addressed specifically in Chapters 3 and 4 of this standard review plan.
The license renewal process is not intended to demonstrate absolute assurance that structures and components will not fail, but rather that there is reasonable assurance that they will perform such that the intended functions are maintained consistent with the CLB during the period of extended operation.
Aging management programs are generally of four types: prevention, mitigation, condition monitoring, and performance monitoring. Prevention programs preclude the effects of aging. For example, coating programs prevent external corrosion of a tank. Mitigation programs attempt to slow the effects of aging. For example, water chemistry programs mitigate internal corrosion of piping. Condition monitoring programs inspect for the presence and extent of aging effects. Examples are the visual examination of concrete structures for cracking, and the ultrasonic examination of pipe wall for erosion-corrosion induced wall thinning. Performance monitoring programs test the ability of a structure or component to perform its intended function(s). For example, the ability of the tubes of heat balances on heat exchangers to transfer heat is tested. More than one type of aging management program may be implemented to ensure that aging effects are managed. For example, in managing internal corrosion of piping, a mitigation program (water chemistry) may be used to minimize susceptibility to corrosion. However, it may also be necessary to have a condition monitoring program (ultrasonic inspection) to verify that corrosion is indeed insignificant.
A.1.2 Branch Technical Position
A.1.2.1 Applicable Aging Effects
1. The determination of applicable aging effects is based on degradations that have occurred and those that potentially could cause structure and component degradation. The materials, environment, stresses, service conditions, operating experience, and other relevant information should be considered in identifying applicable aging effects. The effects of aging on the intended function(s) of structures and components should also be considered.
2. Relevant aging information may be contained in, but is not limited to, the following documents: plant-specific maintenance and inspection records; plant-specific site deviation or issue reports; plant-specific NRC and Institute of Nuclear Power Operations (INPO) inspection reports; plant-specific licensee self-assessment reports; plant-specific and other licensee event reports (LERs); NRC, INPO, and vendor generic communications; GSIs/unresolved safety issues (USIs); NUREG reports; and Electric Power Research Institute (EPRI) reports.
3. If operating experience or other information indicates that a certain aging effect may be applicable and an applicant determines that it is not applicable to its plant, the reviewer may question the absence of this aging effect unless the applicant has provided the basis for this determination in its license renewal application. However, in questioning the absence of the aging effect, a reference and/or basis which provides relevance to aid the applicant in addressing the question should be provided. For example, the question could cite a previous application review, NRC generic communications, engineering judgment, relevant research information, or other industry experience as the basis for the question. Simply citing that the aging effect is listed in the GALL report is not a sufficient basis. For example, the aging effect is applicable to a PWR component, but the applicant's plant is a BWR and does not have such a component. In this example, using the GALL report merely as a checklist is not relevant.
4. An aging effect should be identified as applicable for license renewal even if there is a prevention or mitigation program associated with that aging effect. For example, water chemistry, a coating, or use of cathodic protection could prevent or mitigate corrosion, but corrosion should be identified as applicable for license renewal, and the AMR should consider the adequacy of the water chemistry, coating, or cathodic protection as an aging management program.
5. Specific identification of aging mechanisms is not a requirement; however, it is an option to identify specific aging mechanisms and the associated aging effects in the IPA.
6. The applicable aging effects to be considered for license renewal include those that could result from normal plant operation, including plant/system operating transients and plant shutdown. Specific aging effects from abnormal events need not be postulated for license renewal. However, if an abnormal event has occurred at a particular plant, its contribution to the aging effects on structures and components for license renewal should be considered for that plant. For example, if a resin intrusion has occurred in the reactor coolant system at a particular plant, the contribution of this resin intrusion event to aging should be considered for that plant.
DBEs are abnormal events; they include: design basis pipe break, LOCA, and safe shutdown earthquake (SSE). Potential degradations resulting from DBEs are addressed, as appropriate, as part of the plant's CLB. There are other abnormal events which should be considered on a case-by-case basis. For example, abuse due to human activity is an abnormal event; aging effects from such abuse need not be postulated for license renewal. When a safety-significant piece of equipment is accidentally damaged by a licensee, the licensee is required to take immediate corrective action under existing procedures (see 10 CFR Part 50 Appendix B) to ensure functionality of the equipment. The equipment degradation is not due to aging; corrective action is not necessary solely for the period of extended operation.
However, leakage from bolted connections should not be considered as abnormal events. Although bolted connections are not supposed to leak, experience shows that leaks do occur, and the leakage could cause corrosion. Thus, the aging effects from leakage of bolted connections should be evaluated for license renewal.
An aging effect due to an abnormal event does not preclude that aging effect from occurring during normal operation for the period of extended operation. For example, a certain PWR licensee observed clad cracking in its pressurizer, and attributed that to an abnormal dry out of the pressurizer. Although dry out of a pressurizer is an abnormal event, the potential for clad cracking in the pressurizer during normal operation should be evaluated for license renewal. This is because the pressurizer is subject to extensive thermal fluctuations and water level changes during plant operation, which may result in clad cracking given sufficient operating time. The abnormal dry out of the pressurizer at that certain plant may have merely accelerated the rate of the aging effect.
A.1.2.2 Aging Management for License Renewal
1. An acceptable aging management program should consist of the 10 elements described in Table A.1-1, as appropriate (Ref. 1). These program elements/attributes are discussed further in Position A.1.2.3 below.
2. All programs and activities that are credited for managing a certain aging effect for a specific structure or component should be described. These aging management programs/activities may be evaluated together for the 10 elements described in Table A.1-1, as appropriate.
3. The risk significance of a structure or component could be considered in evaluating the robustness of an aging management program. Probabilistic arguments may be used to assist in developing an approach for aging management adequacy. However, use of probabilistic arguments alone is not an acceptable basis for concluding that, for those structures and components subject to an AMR, the effects of aging will be adequately managed in the period of extended operation. Thus, risk significance may be considered in developing the details of an aging management program for the structure or component for license renewal, but may not be used to conclude that no aging management program is necessary for license renewal.
A.1.2.3 Aging Management Program Elements
A.1.2.3.1 Scope of Program
1. The specific program necessary for license renewal should be identified. The scope of the program should include the specific structures and components of which the program manages the aging.
A.1.2.3.2 Preventive Actions
1. The activities for prevention and mitigation programs should be described. These actions should mitigate or prevent aging degradation.
2. For condition or performance monitoring programs, they do not rely on preventive actions and thus, this information need not be provided. More than one type of aging management program may be implemented to ensure that aging effects are managed.
A.1.2.3.3 Parameters Monitored or Inspected
1. The parameters to be monitored or inspected should be identified and linked to the degradation of the particular structure and component intended function(s).
2. For a condition monitoring program, the parameter monitored or inspected should detect the presence and extent of aging effects. Some examples are measurements of wall thickness and detection and sizing of cracks.
3. For a performance monitoring program, a link should be established between the degradation of the particular structure or component intended function(s) and the parameter(s) being monitored. An example of linking the degradation of a passive component intended function with the performance being monitored is linking the fouling of heat exchanger tubes with the heat transfer intended function. This could be monitored by periodic heat balances. Since this example deals only with one intended function of the tubes, heat transfer, additional programs may be necessary to manage other intended function(s) of the tubes, such as pressure boundary.
A performance monitoring program may not ensure the structure and component intended function(s) without linking the degradation of passive intended functions with the performance being monitored. For example, a periodic diesel generator test alone would not provide assurance that the diesel will start and run properly under all applicable design conditions. While the test verifies that the diesel will perform if all the support systems function, it provides little information related to the material condition of the support components and their ability to withstand DBE loads. Thus, a DBE, such as a seismic event, could cause the diesel supports, such as the diesel embedment plate anchors or the fuel oil tank, to fail if the effects of aging on these components are not managed during the period of extended operation.
4. For prevention and mitigation programs, the parameters monitored should be the specific parameters being controlled to achieve prevention or mitigation of aging effects. An example is the coolant oxygen level that is being controlled in a water chemistry program to mitigate pipe cracking.
A.1.2.3.4 Detection of Aging Effects
1. Detection of aging effects should occur before there is a loss of the structure and component intended function(s). The parameters to be monitored or inspected should be appropriate to ensure that the structure and component intended function(s) will be adequately maintained for license renewal under all CLB design conditions. This includes aspects such as method or technique (e.g., visual, volumetric, surface inspection), frequency, sample size, data collection and timing of new/one-time inspections to ensure timely detection of aging effects. Provide information that links the parameters to be monitored or inspected to the aging effects being managed.
2. Nuclear power plants are licensed based on redundancy, diversity, and defense-in-depth principles. A degraded or failed component reduces the reliability of the system, challenges safety systems, and contributes to plant risk. Thus, the effects of aging on a structure or component should be managed to ensure its availability to perform its intended function(s) as designed when called upon. In this way, all system level intended function(s), including redundancy, diversity, and defense-in-depth consistent with the plant's CLB, would be maintained for license renewal. A program based solely on detecting structure and component failure should not be considered as an effective aging management program for license renewal.
3. This program element describes "when," "where," and "how" program data are collected (i.e., all aspects of activities to collect data as part of the program).
4. The method or technique and frequency may be linked to plant-specific or industry-wide operating experience. Provide justification, including codes and standards referenced, that the technique and frequency are adequate to detect the aging effects before a loss of SC intended function. A program based solely on detecting SC failures is not considered an effective aging management program.
5. When sampling is used to inspect a group of SCs, provide the basis for the inspection population and sample size. The inspection population should be based on such aspects of the SCs as a similarity of materials of construction, fabrication, procurement, design, installation, operating environment, or aging effects. The sample size should be based on such aspects of the SCs as the specific aging effect, location, existing technical information, system and structure design, materials of construction, service environment, or previous failure history. The samples should be biased toward locations most susceptible to the specific aging effect of concern in the period of extended operation. Provisions should also be included on expanding the sample size when degradation is detected in the initial sample.
A.1.2.3.5 Monitoring and Trending
1. Monitoring and trending activities should be described, and they should provide predictability of the extent of degradation and thus effect timely corrective or mitigative actions. Plant-specific and/or industry-wide operating experience may be considered in evaluating the appropriateness of the technique and frequency.
2. This program element describes "how" the data collected are evaluated and may also include trending for a forward look. This includes an evaluation of the results against the acceptance criteria and a prediction regarding the rate of degradation in order to confirm that timing of the next scheduled inspection will occur before a loss of SC intended function. Although aging indicators may be quantitative or qualitative, aging indicators should be quantified, to the extent possible, to allow trending. The parameter or indicator trended should be described. The methodology for analyzing the inspection or test results against the acceptance criteria should be described. Trending is a comparison of the current monitoring results with previous monitoring results in order to make predictions for the future.
A.1.2.3.6 Acceptance Criteria
1. The acceptance criteria of the program and its basis should be described. The acceptance criteria, against which the need for corrective actions will be evaluated, should ensure that the structure and component intended function(s) are maintained under all CLB design conditions during the period of extended operation. The program should include a methodology for analyzing the results against applicable acceptance criteria.
For example, carbon steel pipe wall thinning may occur under certain conditions due to erosion-corrosion. An aging management program for erosion-corrosion may consist of periodically measuring the pipe wall thickness and comparing that to a specific minimum wall acceptance criterion. Corrective action is taken, such as piping replacement, before reaching this acceptance criterion. This piping may be designed for thermal, pressure, deadweight, seismic, and other loads, and this acceptance criterion must be appropriate to ensure that the thinned piping would be able to carry these CLB design loads. This acceptance criterion should provide for timely corrective action before loss of intended function under these CLB design loads.
2. Acceptance criteria could be specific numerical values, or could consist of a discussion of the process for calculating specific numerical values of conditional acceptance criteria to ensure that the structure and component intended function(s) will be maintained under all CLB design conditions. Information from available references may be cited.
3. It is not necessary to justify any acceptance criteria taken directly from the design basis information that is included in the FSAR because that is a part of the CLB. Also, it is not necessary to discuss CLB design loads if the acceptance criteria do not permit degradation because a structure and component without degradation should continue to function as originally designed. Acceptance criteria, which do permit degradation, are based on maintaining the intended function under all CLB design loads.
4. Qualitative inspections should be performed to same predetermined criteria as quantitative inspections by personnel in accordance with ASME Code and through approved site specific programs.
A.1.2.3.7 Corrective Actions
1. Actions to be taken when the acceptance criteria are not met should be described. Corrective actions, including root cause determination and prevention of recurrence, should be timely.
2. If corrective actions permit analysis without repair or replacement, the analysis should ensure that the structure and component intended function(s) will be maintained consistent with the CLB.
A.1.2.3.8 Confirmation Process
1. The confirmation process should be described. It should ensure that preventive actions are adequate and that appropriate corrective actions have been completed and are effective.
2. The effectiveness of prevention and mitigation programs should be verified periodically. For example, in managing internal corrosion of piping, a mitigation program (water chemistry) may be used to minimize susceptibility to corrosion. However, it may also be necessary to have a condition monitoring program (ultrasonic inspection) to verify that corrosion is indeed insignificant.
3. When corrective actions are necessary, there should be follow-up activities to confirm that the corrective actions were completed, the root cause determination was performed, and recurrence is prevented.
A.1.2.3.9 Administrative Controls
1. The administrative controls of the program should be described. They should provide a formal review and approval process.
2. Any aging management programs to be relied on for license renewal should have regulatory and administrative controls. That is the basis for 10 CFR 54.21(d) to require that the FSAR supplement includes a summary description of the programs and activities for managing the effects of aging for license renewal. Thus, any informal programs relied on to manage aging for license renewal must be administratively controlled and included in the FSAR supplement.
A.1.2.3.10 Operating experience
1. Operating experience with existing programs should be discussed. The operating experience of aging management programs, including past corrective actions resulting in program enhancements or additional programs, should be considered. A past failure would not necessarily invalidate an aging management program because the feedback from operating experience should have resulted in appropriate program enhancements or new programs. This information can show where an existing program has succeeded and where it has failed (if at all) in intercepting aging degradation in a timely manner. This information should provide objective evidence to support the conclusion that the effects of aging will be managed adequately so that the structure and component intended function(s) will be maintained during the period of extended operation.
2. An applicant may have to commit to providing operating experience in the future for new programs to confirm their effectiveness.
A.1.3 References
1. NEI 95-10, Revision 3, "Industry Guideline for Implementing the Requirements of 10 CFR Part 54 - The License Renewal Rule," Nuclear Energy Institute, March 2001
Table A.1-1. Elements of an Aging Management Program for License Renewal
| Element | Description |
|---|---|
| 1. Scope of program | Scope of program should include the specific structures and components subject to an AMR for license renewal. |
| 2. Preventive actions | Preventive actions should prevent or mitigate aging degradation. |
| 3. Parameters monitored or inspected |
Parameters monitored or inspected should be linked to the degradation of the particular structure or component intended function(s). |
| 4. Detection of aging effects | Detection of aging effects should occur before there is a loss of structure or component intended function(s). This includes aspects such as method or technique (i.e., visual, volumetric, surface inspection), frequency, sample size, data collection and timing of new/one-time inspections to ensure timely detection of aging effects. |
| 5. Monitoring and trending | Monitoring and trending should provide predictability of the extent of degradation, and timely corrective or mitigative actions. |
| 6. Acceptance criteria | Acceptance criteria, against which the need for corrective action will be evaluated, should ensure that the structure or component intended function(s) are maintained under all CLB design conditions during the period of extended operation. |
| 7. Corrective actions | Corrective actions, including root cause determination and prevention of recurrence, should be timely. |
| 8. Confirmation process | Confirmation process should ensure that preventive actions are adequate and that appropriate corrective actions have been completed and are effective. |
| 9. Administrative controls | Administrative controls should provide a formal review and approval process. |
| 10. Operating experience | Operating experience of the aging management program, including past corrective actions resulting in program enhancements or additional programs, should provide objective evidence to support the conclusion that the effects of aging will be managed adequately so that the structure and component intended function(s) will be maintained during the period of extended operation. |
A.2 Quality Assurance for Aging Management Programs (Branch Technical Position IQMB-1)
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A.2.1 Background
The license renewal applicant is required to demonstrate that the effects of aging on structures and components subject to an Aging Management Review (AMR) will be managed adequately to ensure that their intended functions will be maintained consistent with the CLB of the facility for the period of extended operation. Therefore, those aspects of the AMR process that affect quality of safety-related structures, systems, and components are subject to the quality assurance (QA) requirements of 10 CFR Part 50 Appendix B. For nonsafety-related structures and components subject to an AMR, the existing 10 CFR Part 50 Appendix B QA program may be used by the applicant to address the elements of corrective actions, the confirmation process, and administrative controls, as described in Appendix A.1 (Branch Technical Position RLSB-1). The confirmation process should ensure that preventive actions are adequate and that appropriate corrective actions have been completed and are effective. Administrative controls should provide a formal review and approval process. Reference 1 describes how a license renewal applicant can rely on the existing requirements in 10 CFR Part 50 Appendix B, "Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants," to satisfy these program elements/attributes. The purpose of this branch technical position (IQMB-1) is to describe an acceptable process for implementing the corrective actions, the confirmation process, and administrative controls elements of aging management programs for license renewal.
A.2.2 Branch Technical Position
1. Safety-related structures and components are subject to 10 CFR Part 50 Appendix B requirements, which are adequate to address all quality-related aspects of an aging management program consistent with the CLB of the facility for the period of extended operation.
2. For nonsafety-related structures and components that are subject to an AMR for license renewal, an applicant has an option to expand the scope of its 10 CFR Part 50 Appendix B program to include these structures and components to address corrective actions, the confirmation process, and administrative controls for aging management during the period of extended operation. The reviewer should verify that the applicant has documented such a commitment in the FSAR supplement in accordance with 10 CFR 54.21(d).
3. If an applicant chooses to have alternative means to address corrective actions, the confirmation process, and administrative controls for managing aging of nonsafety-related structures and components that are subject to an AMR for license renewal, the applicant's proposal should be reviewed on a case-by-case basis following the guidance in Appendix A.1 (Branch Technical Position RLSB-1.)
A.2.3 References
2. NUREG-1801, "Generic Aging Lessons Learned (GALL), Appendix," U.S. Nuclear Regulatory Commission, July 2001.
A.3 Generic Safety Issues Related to Aging (Branch Technical Position RLSB-2)
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A.3.1 Background
Unresolved Safety Issues (USIs) and Generic Safety Issues (GSIs) are identified and tracked in the NRC's formal resolution process set forth in NUREG-0933, "A Prioritization of Generic Safety Issues," which is updated periodically (Ref. 1). Appendix B to NUREG-0933 contains a listing of those issues that are applicable to operating and future plant. NUREG-0933 is a source of information on generic concerns identified by the NRC. Some of these concerns may be related to the effects of aging or Time-Limited Aging Analyses (TLAAs) for systems, structures, or components within the scope of license renewal review. The purpose of this branch technical position (RLSB-2) is to address the license renewal treatment of an aging effect or a TLAA which is a subject of an USI or a GSI (60 FR 22484).
Table A.3-1 provides examples to help determine whether a USI or GSI should or should not be specifically addressed for license renewal, based on lessons learned from the staff review of the initial license renewal applications. However, two of these examples (GSI-23 and -190) have been resolved by the staff. They are included in the examples for illustrative purposes.
A.3.2 Branch Technical Position
A.3.2.1 Treatment of GSIs
1. The license renewal rule requires that aging effects be managed to ensure that the structure and component intended function(s) are maintained and that TLAAs are evaluated for license renewal. Thus, all applicable aging effects of structures and components subject to an AMR and all TLAAs must be evaluated, regardless of whether they are associated with GSIs or USIs.
2. USIs and HIGH- and MEDIUM-priority issues described in NUREG-0933 Appendix B (Ref. 1) that involve aging effects for structures and components subject to an AMR or TLAAs should be specifically addressed. The version of NUREG-0933 that is current on the date 6 months before the date of the license renewal application should be used to identify such issues. Prior to Safety Evaluation Report (SER) completion, any new issues contained in later versions of NUREG-0933 should be reviewed and resolved if determined to be applicable to the applicant's plant. New issues may be addressed by using one of the approaches described in Position A.3.2.2 below.
3. New generic safety issues, designated as USI, HIGH-, or MEDIUM- priority after the application has been submitted, that involve aging effects for structures and components subject to an aging management review or TLAA should be submitted in the annual update of the application.
4. During the preparation and review of a license renewal application, an applicant or the NRC may become aware of an aging management or TLAA issue that may be generically applicable to other nuclear plants. If issues may have generic applicability (but are not yet part of the formal GSIs resolution process as identified in NUREG-0933), an applicant should still address the issue to demonstrate that the effects of aging are or will be managed adequately or that TLAAs have been evaluated for the period of extended operation.
A.3.2.2 Approaches for Addressing GSIs (60 FR 22484)
One of the following approaches may be used:
1. If resolution has been achieved before issuance of a renewed license, implementation of that resolution is incorporated within the license renewal application. The plant-specific implementation information should be provided.
2. A technical rationale is provided that demonstrates that the CLB will be maintained until some later time in the period of extended operation, at which point one or more reasonable options (for example, replacement, analytical evaluation, or a surveillance/maintenance program) would be available to adequately manage the effects of aging. An applicant would have to describe the basis for concluding that the CLB is maintained during the period of extended operation, and briefly describe options that are technically feasible during the period of extended operation to manage the effects of aging, but would not have to preselect which option would be used.
3. An aging management program is developed that, for that plant, incorporates a resolution to the aging effects issue.
4. An amendment of the CLB (as a separate action outside the license renewal application) is proposed that, if approved, would remove the intended function(s) from the CLB. The proposed CLB amendment is reviewed under 10 CFR Part 50 and is not a review area for license renewal.
A.3.3 References
1. NUREG-0933, "A Prioritization of Generic Safety Issues."
2. NRC Regulatory Issue Summary 2000-02, "Closure of Generic Safety Issue 23, Reactor Coolant Pump Seal Failure," February 15, 2000.
3. Letter from Ashok C. Thadani of the Office of Nuclear Regulatory Research, NRC, to William D. Travers, Executive Director of Operations, NRC, dated December 26, 1999.
4. SECY 94-225, "Issuance of Proposed Rulemaking Package on GSI-23, Reactor Coolant Pump Seal Failure," August 26, 1994.
5. Information Notice 93-61, "Excessive Reactor Coolant Leakage Following a Seal Failure in a Reactor Coolant Pump or Reactor Recirculation Pump," August 9, 1993.
6. Letter to Doug Walters, Nuclear Energy Institute, from Christopher I Grimes, NRC, dated June 2, 1998.
Table A.3-1. Examples of Generic Safety Issues that Should/Should Not Be Specifically Addressed for License Renewal and Basis for Disposition
| Example | Disposition |
|---|---|
| GSI-23, "Reactor Coolant Pump Seal Failures" | This issue relates to reactor coolant pump seal failures, which challenge the makeup capacity of the emergency core cooling system in PWRs. Although GSI-23 originally addressed seal performance both during normal operation and during loss of seal cooling conditions, it has been modified to address only seal performance during loss of seal cooling conditions (Refs. 4 and 5). Loss of all seal cooling may cause the reactor coolant pump seals to fail or leak excessively. Because the reactor coolant pump seal performance during loss of seal cooling conditions is not an issue that involves AMR or TLAA, GSI-23 need not be specifically addressed for license renewal (Ref. 2). |
| GSI-168, "Environmental Qualification of Electrical Equipment" | This issue relates to aging of electrical equipment that is subject to environmental qualification requirements. Environmental qualification is a TLAA for license renewal. Thus, GSI-168 should be specifically addressed for license renewal (Ref. 6). |
| GSI-173.A, "Spent Fuel Storage Pool: Operating Experience" | This issue relates to the potential for a sustained loss of spent fuel pool cooling capacity and the potential for a substantial loss of spent fuel pool coolant inventory. The staff evaluated the issue and concluded that no actions will be taken for operating plants. As indicated in NUREG-0933, the staff is pursuing regulatory improvement changes to RG 1.13, "Spent Fuel Storage Facility Design Basis," and NUREG-0800, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants." Thus, GSI-173.A need not be specifically addressed for license renewal. |
| GSI-190, "Fatigue Evaluation of Metal Components for 60-Year Plant Life" | This issue relates to environmental effects on fatigue of reactor coolant system components for 60 years. Fatigue is also a TLAA for license renewal. Thus, GSI-190 was specifically addressed for license renewal by the initial license renewal applicants. This GSI has now been resolved (Ref. 3). |
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1. 1 NRC Regulatory Guide 1.188, "Standard Format and Content for Applications to Renew Nuclear Power Plant Operating Licenses" (Ref. 1), provides guidance on the format and content of a renewal application.

