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Removal of the Schedule for the Withdrawal of Reactor Vessel Material Specimens from Technical Specifications (Generic Letter 91-01)
January 4, 1991 TO: ALL HOLDERS OF OPERATING LICENSES OR CONSTRUCTION PERMITS FOR NUCLEAR POWER REACTORS SUBJECT: REMOVAL OF THE SCHEDULE FOR THE WITHDRAWAL OF REACTOR VESSEL MATERIAL SPECIMENS FROM TECHNICAL SPECIFICATIONS (Generic Letter 91-01) Technical specifications (TS) include limiting conditions for operation that establish pressure and temperature limits for the reactor coolant system. The limits are defined by TS figures that provide an acceptable range of operating temperatures and pressures for heatup, cooldown, criticality, and inservice leak and hydrostatic testing. These limits are generally valid for a specified number of effective full-power years. A program for reactor vessel material surveillance ensures the availability of data to update the inservice operating temperature and pressure limits. This program will assist in fulfilling the requirements of Appendix H to Part 50 of Title 10 of the Code of Federal Regulations (10 CFR) to prevent brittle fracture of the reactor vessel. The surveillance requirements associated with these limits specify the withdrawal schedule for the reactor vessel material specimens. Recently, the staff of the U.S. Nuclear Regulatory Commission (NRC) approved a request to remove this schedule from the TS for the Joseph M. Farley Nuclear Plant. This TS change was requested because Section II.B.3 of Appendix H to 10 CFR Part 50 requires the submittal to, and approval by, the NRC of a proposed withdrawal schedule for material specimens before implementation. Hence, the placement of this schedule in the TS duplicates the controls on changes to this schedule that have been established by Appendix H. Therefore, the staff concluded that, because this duplication is unnecessary, the removal of this TS schedule as a line-item improvement is consistent with the Commission Policy Statement on TS Improvements. The enclosed guidance addresses the preparation of a request for a license amendment for this TS change. Licensees and applicants that plan to adopt this line-item TS improvement are encouraged to propose changes to their TS that are consistent with the guidance in the Enclosure. The NRC project manager for the facility will review these amendment requests. Please contact the project manager or the contact identified below if you have questions on this matter. This letter does not require any licensee to propose changes to its plant TS. Action taken in response to the guidance provided in this generic letter 9012310078 . Generic Letter 91-01 - 2 - January 4, 1991 is voluntary and is not a backfit under 10 CFR 50.109. Therefore, Office of Management and Budget clearance is not required. Sincerely, James G. Partlow Associate Director for Projects Office of Nuclear Reactor Regulation Enclosure: As stated Contact: Tom Dunning, OTSB/NRR (301) 492-1189 . Generic Letter 91-01 Enclosure GUIDANCE FOR THE REMOVAL OF THE WITHDRAWAL SCHEDULE FOR REACTOR VESSEL MATERIAL SPECIMENS FROM TECHNICAL SPECIFICATIONS Introduction: This enclosure provides guidance for the preparation of a request for a license amendment to remove from the technical specifications (TS) the schedule for the withdrawal of reactor vessel material surveillance specimens. The control of changes to this schedule by way of a license amendment to modify the TS duplicates the requirements of Section II.B.3 of Appendix H to Part 50 of Title 10 of the Code of Federal Regulations (10 CFR). These requirements address the submittal of a proposed withdrawal schedule, as specified in 10 CFR 50.4, and NRC approval before its implementation. Discussion: The limiting conditions for operation (LCO) for the reactor coolant system include operating limits on pressure and temperature that are defined in figures that provide an acceptable region for operation during heatup, cooldown, criticality, and inservice leak and hydrostatic testing. An associated surveillance requirement addresses the frequency of verifying that operation is within the specified limits during these operating conditions. In addition, a separate surveillance includes the requirement that reactor vessel material surveillance specimens be removed and examined to determine changes in material properties, as required by 10 CFR Part 50, Appendix H, and in accordance with the schedule in the referenced TS table. The reference to this table along with the TS table providing the schedule for the withdrawal of reactor vessel material surveillance specimens may be removed from this surveillance requirement. This surveillance requirement may also specify that the results of these examinations shall be used to update the TS figures for the pressure and temperature operating limits. If this requirement exists, it shall be retained. The Bases Section for this TS provides a detailed description of the bases for this LCO and the associated surveillance requirements. The standard technical specifications (STS) bases reference the TS table that provides the schedule for surveillance specimen withdrawal. The bases states that the heatup and cooldown curves are recalculated when data from the surveillance specimens indicate a change in material properties that exceeds the limiting value of those properties that were used to develop the existing pressure and temperature limits. Finally, the STS Bases Section includes a table of the initial values of reactor vessel material properties and includes figures showing the effects of neutron fluence on the material characteristics and the predicted shifts in material characteristics. The current STS bases provide extensive background information on the use of the data obtained from material specimens. This background information clearly defines the purpose and relationship of this information to the requirements included in the regulations and the American Society of Mechanical Engineers (ASME) Code. Therefore, the removal of the schedule for specimen withdrawal from the TS will not result in any loss of clarity related to regulatory requirements of Appendix H to 10 CFR Part 50. If the Bases Section of this TS includes a reference to the TS table that provides the schedule for material specimen withdrawal that is being removed from . Generic Letter 91-01 - 2 - Enclosure the TS, this section should be updated to reflect the removal of this TS table. However, to obtain a readily available copy of the NRC-approved version of the specimen withdrawal schedule, licensees should provide a commitment to include this schedule in the next revision of the updated safety analysis report (USAR). Summary: The removal from the TS of the schedule for the withdrawal of reactor vessel material surveillance specimens will not result in any loss of regulatory control because changes to this schedule are controlled by the requirements of Appendix H to 10 CFR Part 50. In addition, to ensure that the surveillance specimens are withdrawn at the proper time, the surveillance requirements in the TS on pressure and temperature limits must indicate that the specimens shall be removed and examined to determine changes in their material properties, as required by Appendix H. A request for a license amendment to remove this table from the TS may be made based upon this guidance. Licensees should include an updated Bases Section for this TS with this proposal if changes to the Bases Section are necessary to remove references to the table being removed from the TS. Also, the licensee should commit to maintain the NRC-approved version of the specimen withdrawal schedule in the USAR.
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