- Definitions
Section 1.0, "Definitions," should contain the following language:
PRESSURE TEMPERATURE LIMITS REPORT (PTLR)
The PTLR is the unit-specific document that provides the reactor vessel P/T limits and setpoints, including heatup and cooldown rates, for the current reactor vessel fluence period. These P/T limits shall be determined for each fluence period or effective full-power years (EFPYs) in accordance with Specification 5.X.X.X. Plant operation within these operating limits is addressed in LCO 3.X.X, "RCS Pressure and Temperature (P/T) Limits," and LCO 3.X.X, "Low Temperature Overpressure Protection (Ltop) System."
- Limiting Conditions for Operation (LCOs) and Bases
LCO 3.X.X, "RCS Pressure and Temperature (P/T) Limits," and LCO 3.X.X, "Low Temperature Overpressure Protection (Ltop) System," must reference the PTLR as the document where the limits and curves can be found as demonstrated in the attached model TS. The bases for these LCOs should be modified accordingly.
- Administrative Controls
Section 5.X, "Administrative Controls," Subsection 5.X.X, "Reporting Requirements," must contain the following information:
Section 5.X.X.X Reactor Coolant System (RCS) PRESSURE AND TEMPERATURE LIMITS REPORT (PTLR)
a. RCS pressure and temperature limits for heatup, cooldown, Ltop, criticality, and hydrostatic testing as well as heatup and cooldown rates shall be established and documented in the PTLR for the following: [The individual specifications that address RCS pressure and temperature limits must be referenced here.] b. The analytical methods used to determine the RCS pressure and temperature limits shall be those previously reviewed and approved by the NRC, specifically those described in the following document(s): [Identify the NRC staff approval document(s) by date.] c. The PTLR shall be provided to the NRC upon issuance for each reactor vessel fluence period or EFPYs and for any revision or supplement thereto.
b. The analytical methods used to determine the RCS pressure and temperature limits shall be those previously reviewed and approved by the NRC, specifically those described in the following document(s): [Identify the NRC staff approval document(s) by date.]
c. The PTLR shall be provided to the NRC upon issuance for each reactor vessel fluence period or EFPYs and for any revision or supplement thereto.
MODEL SAFETY EVALUATION (SE)
Underscored blank spaces are to be completed on the basis of the applicable facility information. The information in brackets should be used, as applicable, on a plant-specific basis.
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. TO FACILITY OPERATING LICENSE NFP- [UTILITY NAME] [PLANT NAME], [UNIT ] DOCKET NO. 50-
1.0 INTRODUCTION
By letter dated , 19 , [utility name] (the licensee) proposed changes to the technical specifications (TS) for [plant name]. The requested changes are the relocation of the pressure temperature (P/T) limit curves and low temperature overpressure protection (Ltop) system limits to the [named plant- specific report] and the referencing of that report in the affected limiting conditions for operation and bases. The proposed changes also include the addition of the [named plant-specific report] to the definitions section of the TS and the addition of a new section to the reporting requirements in the administrative controls section of the TS delineating the necessary reports. Guidance on the proposed changes was developed by the Nuclear Regulatory Commission (NRC) on the basis of a proposal by the owners groups during the development of the improved standard technical specifications (STS). This guidance was provided to all power reactor licensees and applicants by Generic Letter YY-XX, dated , 19 .
2.0 BACKGROUND
Section 182a of the Atomic Energy Act (the Act) requires applicants for nuclear power plant operating licenses to include TS as part of the license. The Commission's regulatory requirements related to the content of TS are set forth in 10 CFR 50.36. That regulation requires that the TS include items in five specific categories: (1) safety limits, limiting safety system settings and limiting control settings; (2) limiting conditions for operation; (3) surveillance requirements; (4) design features; and (5) administrative controls, and states also that the Commission may include such additional TS as it finds to be appropriate. However, the regulation does not specify the particular requirements to be included in a plant's TS.
The Commission has provided guidance for the contents of TS in its "Final Policy Statement on Technical Specifications Improvements for Nuclear Power Reactors" (Final Policy Statement), 58 FR 39132 (July 22, 1993), in which the Commission indicated that compliance with the Final Policy Statement satisfies Section 182a of the Act. In particular, the Commission indicated that certain items could be relocated from the TS to licensee-controlled documents, consistent with the standard enunciated in Portland General Electric Co. (Trojan Nuclear Plant), ASLAB-531, 9 NRC 263, 273 (1979). In that case, the Atomic Safety and Licensing Appeal Board indicated that "technical specifications are to be reserved for those matters as to which the imposition of rigid conditions or limitations upon reactor operation is deemed necessary to obviate the possibility of an abnormal situation or event giving rise to an immediate threat to the public health and safety."
Consistent with this approach, the Final Policy Statement identified four criteria to be used in determining whether a particular matter is required to be included in the TS, as follows: (1) installed instrumentation that is used to detect, and indicate in the control room, a significant abnormal degradation of the reactor coolant pressure boundary; (2) a process variable, design feature, or operating restriction that is an initial condition of a design basis accident or transient analysis that either assumes the failure of or presents a challenge to the integrity of a fission product barrier; (3) a structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier; (4) a structure, system, or component which operating experience or probabilistic safety assessment has shown to be significant to public health and safety. As a result, existing TS requirements which fall within or satisfy any of the criteria in the Final Policy Statement must be retained in the TS, while those TS requirements which do not fall within or satisfy these criteria may be relocated to other licensee-controlled documents.
3.0 EVALUATION
All components of the reactor coolant system (RCS) are designed to withstand the effects of cyclic loads resulting from system pressure and temperature changes. These loads are introduced by heatup and cooldown operations, power transients, and reactor trips. In accordance with Appendix G to 10 CFR Part 50, TS limit the pressure and temperature changes during RCS heatup and cooldown within the design assumptions and the stress limits for cyclic operation. These limits are defined by P/T limit curves for heatup, cooldown, Ltop, and inservice leak and hydrostatic testing. Each curve defines an acceptable region for normal operation. The curves are used for operational guidance during heatup and cooldown maneuvering, when pressure and temperature indications are monitored and compared to the applicable curve to determine that operation is within the allowable region.
[Reviewer Note: While the NRC is completing the rulemaking process for revisions to 10 CFR 50.55a and 10 CFR Part 50, Appendix G, licensees using the American Society of Mechanical Engineers Boiler and Pressure Vessel Code Case N-514 must request an exemption from Appendix G. The following or similar language should be included in the SE:
The licensee used the American Society of Mechanical Engineers Boiler and Pressure Vessel Code Case N-514 and requested an exemption from Appendix G by justifying why Appendix G cannot be met and demonstrating that a specific exemption was warranted under 10 CFR 50.12.]
The LTOP system controls RCS pressure at low temperatures so that the integrity of the reactor coolant pressure boundary is not compromised by violating 10 CFR Part 50, Appendix G. [Reviewer Note: The following sentences should be modified to identify the specific Ltop system being referred to in the SE: The Ltop system for pressure relief, for most plants, consists of power-operated relief valves (PORVs), residual heat removal suction relief valves, or a combination of both. Some plants have one PORV. The Ltop system limits consist of PORV and RHR setpoints. The RHR suction relief valves do not have variable pressure and temperature lift setpoints like the PORVs and, therefore, are still addressed in the TS.] The Ltop system is reevaluated each time the P/T limit curves are revised to ensure that it meets its intended function.
The licensee-proposed changes to the TS are in accordance with the guidance in Generic Letter YY-XX, as follows:
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