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Category:Code Relief or Alternative
MONTHYEARML24068A2492024-04-22022 April 2024 – Authorization and Safety Evaluation for Alternative Request No. I6-RR-01 ML24071A0912024-04-22022 April 2024 Issuance of Relief Request I6-RR-03 - Extension of the Unit 2 Steam Generator Primary Nozzle Dissimilar Metal Welds Sixth 10-Year Inservice Inspection Program Interval ML23279A0672023-11-0909 November 2023 Issuance of Relief Request I6 RR 02 - Examination of the Unit 2 Steam Generator Feedwater Nozzle Extension to Nozzle Weld Sixth 10 Year Inservice Inspection Program Interval ML20036F2612020-03-0404 March 2020 Approval of Relief Request 1-RR-13 and 2-RR-13 Regarding Extension of Inspection Interval for Point Beach Unit 1 and Unit 2 Reactor Pressure Vessel Welds from 10 to 20 Years ML19339H7472019-12-13013 December 2019 Approval of Relief Request 2-RR-17 Regarding Steam Generator Primary Nozzle Dissimilar Metal Welds Inspection Interval ML18106B1212018-04-25025 April 2018 Proposed Alternative to Use Encoded Phased Array Ultrasonic Examination Techniques L-2017-121, Proposed Alternative for the Use of Encoded Phased Array Ultrasonic Examination Techniques in Lieu of Radiography2017-07-24024 July 2017 Proposed Alternative for the Use of Encoded Phased Array Ultrasonic Examination Techniques in Lieu of Radiography ML16330A1182016-12-15015 December 2016 NextEra Fleet - Safety Evaluation for Proposed Alternative to the American Society of Mechanical Engineers Operation and Maintenance Code by Adoption of Approved Code Case OMN-20, Inservice Test Frequency (CAC Nos. MF8195 Through MF8201) ML16063A0582016-03-22022 March 2016 Approval of Relief Request 2-RR-11; Steam Generator Nozzle to Safe-End Dissimilar Metal (DM) Weld Inspection ML15246A3052015-09-16016 September 2015 Evaluation of Relief Request RR-10 - Examination of Feedwater Nozzle Extension to Nozzle Weld Fifth 10-Year Inservice Program Interval ML15127A2912015-05-20020 May 2015 Relief Request RR-8, Relief from the Requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code for Examination of Buried Components NRC 2015-0025, Requests Relief from Performing Inservice Testing (ISI) of Relief Valve 1CC-00763B2015-05-14014 May 2015 Requests Relief from Performing Inservice Testing (ISI) of Relief Valve 1CC-00763B ML15099A0182015-05-0707 May 2015 Relief Request RR-9, Proposed Alternative from the Requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code for System Leakage Test ML14343A0512014-12-10010 December 2014 Relief from the Requirements of the ASME Code for Re-Examination of the Reactor Pressure Vessel a Inlet Nozzle Weld for the Fifth Ten-Year Inservice Inspection Program Interval ML13329A0312013-12-20020 December 2013 Relief from the Requirements of ASME B&PV Code, Section XI, for the Fourth 10-Year ISI Interval (RR-4L1) ML13079A1412013-03-19019 March 2013 CFR 50.55a Request, Relief Request RR-4L3 Inservice Inspection Impracticality Examination Limitations Due to Configuration Fourth Ten-Year Inservice Inspection Program Interval NRC 2013-0020, CFR 50.55a Request, Relief Request RR-4L3 Inservice Inspection Impracticality Examination Limitations Due to Configuration Fourth Ten-Year Inservice Inspection Program Interval2013-03-19019 March 2013 CFR 50.55a Request, Relief Request RR-4L3 Inservice Inspection Impracticality Examination Limitations Due to Configuration Fourth Ten-Year Inservice Inspection Program Interval ML13064A4252013-03-18018 March 2013 Relief Request 1-RR-4 Re-Examination of the Unit 1 RPV Indication on the a Inlet Nozzle Weld ML12286A1042012-11-15015 November 2012 Evaluation of Relief Requests RR-2 & RR-3 (ME7974 & ME7975) ML0617103642006-07-0303 July 2006 Monticello Nuclear Generating Plant, Palisades Nuclear Plant, Point Beach Nuclear Plant Units 1 and 2, Prairie Island Nuclear Generating Plant, Units 1 and 2 - Use of ASME Code Case N-513-2 ML0527001972006-01-18018 January 2006 Relief Request - Reactor Vessel Closure Head Penetration Flaw Characterization Relief Request MR 02-018-2, Revision 2 ML0526503122005-09-27027 September 2005 Relief Requests - the Previsions of ASME Section XI, IWA-5244, Buried Components, RR-1-26 and RR-2-34 NRC 2005-0084, Reactor Vessel Closure Head Penetration Flaw Characterization Relief Request MR 02-018-2, Revision 22005-07-0101 July 2005 Reactor Vessel Closure Head Penetration Flaw Characterization Relief Request MR 02-018-2, Revision 2 NRC 2005-0016, Relief Request from the Provisions of ASME Section Xl, IWA-4422.2.2, Defect Removal Followed by Welding or Brazing, Relief Request 162005-02-0404 February 2005 Relief Request from the Provisions of ASME Section Xl, IWA-4422.2.2, Defect Removal Followed by Welding or Brazing, Relief Request 16 NRC 2005-0015, Relief Request from the Provisions of ASME Section XI, IWA-5244, Buried Components, Relief Request 152005-01-21021 January 2005 Relief Request from the Provisions of ASME Section XI, IWA-5244, Buried Components, Relief Request 15 ML0408601612004-04-0101 April 2004 Request for Relief VRR 03-01 on a One Time Basis for Performing Inservice Testing of Relief Valve 1RH-861C ML0401607382004-02-26026 February 2004 Prairie, Units 1 and 2, Kewaunee, Point Beach, Units 1 and 2, Palisades, Re Request for Alternatives to ASME Section XI, Appendix Viii, Supplement 10 ML0323104022003-09-10010 September 2003 Relief, MR 02 018-2 Pertaining to Reactor Vessel Closure Head Penetration Repair ML0306203282003-03-21021 March 2003 Relief, Use of Code Case N-600 for the Fourth 10-Year Interval, MB5403 and MB5404 ML0225401092003-03-21021 March 2003 Relief Request No 8 - Requirement for Scheduling of Components for Examination ML0302101262003-02-27027 February 2003 Relief, Alternative to Examine All Three Vessels of the Regenerative Heat Exchanger, MB5401 & MB5402 ML0225300232002-10-0808 October 2002 Relief, Granted for ASME Code Section XI, Relief Request 6 Regarding Evaluation of Leakage with Bolting In-Place ML0225300062002-10-0808 October 2002 Code Relief, ASME Code Section XI, Relief Request 5 Regarding Visual Examination of Insulted Bolting on Borated Systems NRC 2002-0073, Reactor Vessel Closure Head Penetration Repair Relief Requests MR 02-018-1 and MR 02-018-22002-08-28028 August 2002 Reactor Vessel Closure Head Penetration Repair Relief Requests MR 02-018-1 and MR 02-018-2 2024-04-22
[Table view] Category:Letter type:NRC
MONTHYEARNRC 2024-0007, Ile Post-Exam Submittal Letter2024-03-18018 March 2024 Ile Post-Exam Submittal Letter NRC-2024-0026, Ile Proposed Exam Submittal Letter2023-12-20020 December 2023 Ile Proposed Exam Submittal Letter NRC 2023-0013, Response to Regulatory Information Summary 2023-01 Preparation and Scheduling of Operator Licensing Examinations2023-07-0707 July 2023 Response to Regulatory Information Summary 2023-01 Preparation and Scheduling of Operator Licensing Examinations NRC 2023-0006, Post-Exam Submittal Cover Letter2023-03-0101 March 2023 Post-Exam Submittal Cover Letter NRC 2023-0005, Report of Changes to Emergency Plan2023-02-21021 February 2023 Report of Changes to Emergency Plan NRC 2022-0032, Sixth 10-Year Interval Inservice Testing (1ST) Program Plan2022-09-30030 September 2022 Sixth 10-Year Interval Inservice Testing (1ST) Program Plan NRC 2022-0025, License Amendment Request 295, Beacon Power Distribution Monitoring System2022-09-26026 September 2022 License Amendment Request 295, Beacon Power Distribution Monitoring System NRC 2022-0019, Report of Changes to Emergency Plan2022-07-13013 July 2022 Report of Changes to Emergency Plan NRC 2022-0022, Response to Request for Supplemental Information (Rsi) Regarding License Amendment Request (LAR) 297, Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2,2022-07-11011 July 2022 Response to Request for Supplemental Information (Rsi) Regarding License Amendment Request (LAR) 297, Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, NRC 2022-0015, Fall 2021 Unit 2 (U2R38) Steam Generator Tube Inspection Report2022-04-27027 April 2022 Fall 2021 Unit 2 (U2R38) Steam Generator Tube Inspection Report NRC 2022-0014, 2021 Annual Monitoring Report2022-04-14014 April 2022 2021 Annual Monitoring Report NRC 2021-0012, Core Operating Limits Report (COLR) Unit 1 Cycle 41 (U 1 C41)2022-04-0707 April 2022 Core Operating Limits Report (COLR) Unit 1 Cycle 41 (U 1 C41) NRC 2022-0003, License Amendment Request 296, Application for Technical Specification Improvement to Eliminate Requirements for Post-Accident Systems Using the Consolidated Line Item Improvement Process2022-03-25025 March 2022 License Amendment Request 296, Application for Technical Specification Improvement to Eliminate Requirements for Post-Accident Systems Using the Consolidated Line Item Improvement Process NRC 2022-0006, Notification of Deviation from Pressurized Water Owners Group (PWROG) Report WCAP-17451-P, Revision 1, Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections2022-02-22022 February 2022 Notification of Deviation from Pressurized Water Owners Group (PWROG) Report WCAP-17451-P, Revision 1, Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections NRC 2022-0004, Report of Changes to Emergency Plan2022-02-0909 February 2022 Report of Changes to Emergency Plan NRC 2022-0005, Refueling Outage U2R38 Owner'S Activity Report for Class 1, 2, 3 and Mc ISI Examinations2022-02-0101 February 2022 Refueling Outage U2R38 Owner'S Activity Report for Class 1, 2, 3 and Mc ISI Examinations NRC 2022-0001, Report of Changes to Emergency Plan2022-01-11011 January 2022 Report of Changes to Emergency Plan NRC 2021-0046, Core Operating Limits Report (COLR) Unit 2 Cycle 39 (U2C39) and Changes to Unit 1 COLR Unit 1 Cycle 40 (U1C40)2021-10-28028 October 2021 Core Operating Limits Report (COLR) Unit 2 Cycle 39 (U2C39) and Changes to Unit 1 COLR Unit 1 Cycle 40 (U1C40) NRC 2021-0031, Registration of Holtec Hi STORM Casks HI-STORM-37-054, HI-STORM-37-055, and HI-STORM-37-0562021-07-15015 July 2021 Registration of Holtec Hi STORM Casks HI-STORM-37-054, HI-STORM-37-055, and HI-STORM-37-056 NRC 2021-0027, Registration of Holtec Historm Casks HISTORM-37-051, HISTORM-37-052, and HISTORM-37-0532021-06-30030 June 2021 Registration of Holtec Historm Casks HISTORM-37-051, HISTORM-37-052, and HISTORM-37-053 NRC 2021-0028, Generic Letter 2004-02 Containment Sump Debris Transport Calculation Non-Conservatism2021-06-23023 June 2021 Generic Letter 2004-02 Containment Sump Debris Transport Calculation Non-Conservatism NRC 2021-0021, 2020 Annual Monitoring Report2021-04-29029 April 2021 2020 Annual Monitoring Report NRC 2021-0019, Response to Regulatory Information Summary 2021-01 Preparation and Scheduling of Operator Licensing Examinations2021-04-22022 April 2021 Response to Regulatory Information Summary 2021-01 Preparation and Scheduling of Operator Licensing Examinations NRC-2021-0011, Technical Specification Bases and Technical Requirement Manual Change Summary2021-04-0202 April 2021 Technical Specification Bases and Technical Requirement Manual Change Summary NRC-2021-0010, CFR 50.59 Evaluation and Commitment Change Summary Report2021-04-0202 April 2021 CFR 50.59 Evaluation and Commitment Change Summary Report NRC 2021-0006, Report of Changes to Emergency Plan2021-03-18018 March 2021 Report of Changes to Emergency Plan NRC 2021-0005, Withdrawal of Exemption Request Supporting Updated Final Response to NRC Generic Letter 2004-022021-02-11011 February 2021 Withdrawal of Exemption Request Supporting Updated Final Response to NRC Generic Letter 2004-02 NRC 2021-0003, Refueling 39 (U1 R39) Reactor Coolant Pump Analytical Evaluation Report2021-01-21021 January 2021 Refueling 39 (U1 R39) Reactor Coolant Pump Analytical Evaluation Report NRC 2021-0002, Refueling Outage U1 R39 Owner'S Activity Report for Class 1, 2, 3 and Mc ISI Examinations2021-01-21021 January 2021 Refueling Outage U1 R39 Owner'S Activity Report for Class 1, 2, 3 and Mc ISI Examinations NRC 2021-0001, Report of Changes to Emergency Plan2021-01-13013 January 2021 Report of Changes to Emergency Plan NRC 2020-0044, Response to Request for Additional Information Request for Exemption from 10 CFR 73, Appendix B, Section VI Regarding Annual Force-On-Force Exercise2020-12-0808 December 2020 Response to Request for Additional Information Request for Exemption from 10 CFR 73, Appendix B, Section VI Regarding Annual Force-On-Force Exercise NRC 2020-0032, Application for Subsequent Renewed Facility Operating Licenses2020-11-16016 November 2020 Application for Subsequent Renewed Facility Operating Licenses NRC 2020-0039, Core Operating Limits Report (COLR) Unit 1 Cycle 40 (U1 C40)2020-11-0202 November 2020 Core Operating Limits Report (COLR) Unit 1 Cycle 40 (U1 C40) NRC 2020-0031, NextEra Energy Point Beach, LLC Response to Apparent Violation in NRC Inspection Report 05000266/2020012, 05000301/2020012: EA-20-0812020-10-0505 October 2020 NextEra Energy Point Beach, LLC Response to Apparent Violation in NRC Inspection Report 05000266/2020012, 05000301/2020012: EA-20-081 NRC 2020-0029, Supplement to License Amendment Request (LAR) 293, One-Time Extension of Renewed Facility Operating License Condition 4.1, Containment Building Construction Truss2020-09-15015 September 2020 Supplement to License Amendment Request (LAR) 293, One-Time Extension of Renewed Facility Operating License Condition 4.1, Containment Building Construction Truss NRC 2020-0024, Response to Request for Additional Information Request for Exemption from Certain Operator Requalification Requirements2020-08-17017 August 2020 Response to Request for Additional Information Request for Exemption from Certain Operator Requalification Requirements NRC 2020-0020, License Amendment Request (LAR) 293, One-Time Extension of Renewed Facility Operating License Condition 4.1, Containment Building Construction Truss2020-08-13013 August 2020 License Amendment Request (LAR) 293, One-Time Extension of Renewed Facility Operating License Condition 4.1, Containment Building Construction Truss NRC 2020-0021, Response to NRC Inspection Report and Preliminary White Finding2020-08-12012 August 2020 Response to NRC Inspection Report and Preliminary White Finding NRC 2020-0023, NextEra Energy Point Beach, LLC - Revised Response to Regulatory Information Summary 2020-01, Preparation and Scheduling of Operator Licensing Examinations2020-08-12012 August 2020 NextEra Energy Point Beach, LLC - Revised Response to Regulatory Information Summary 2020-01, Preparation and Scheduling of Operator Licensing Examinations NRC 2020-0018, Report of Changes to Emergency Plan2020-07-15015 July 2020 Report of Changes to Emergency Plan NRC-2020-0016, Supplement to Exemption Request for Access Authorization and Fitness for Duty Requirements Due to COVID-19 Pandemic2020-06-12012 June 2020 Supplement to Exemption Request for Access Authorization and Fitness for Duty Requirements Due to COVID-19 Pandemic NRC 2020-0012, Refueling Outage U2R37 Owner'S Activity Report for Class 1, 2, 3 and Mc ISI Examinations2020-05-20020 May 2020 Refueling Outage U2R37 Owner'S Activity Report for Class 1, 2, 3 and Mc ISI Examinations NRC 2020-0008, Report of Changes to Emergency Plan2020-04-0606 April 2020 Report of Changes to Emergency Plan NRC 2020-0007, Core Operating Limits Report (COLR) Unit 2 Cycle 28 (U2C38)2020-03-27027 March 2020 Core Operating Limits Report (COLR) Unit 2 Cycle 28 (U2C38) NRC 2020-0003, License Amendment Request 289: Tornado Missile Protection Licensing Basis2020-02-0606 February 2020 License Amendment Request 289: Tornado Missile Protection Licensing Basis NRC 2020-0001, Pressure Temperature Limits Report (PTLR)2020-01-0909 January 2020 Pressure Temperature Limits Report (PTLR) NRC 2019-0044, Report of Changes to Emergency Plan2019-11-0101 November 2019 Report of Changes to Emergency Plan NRC 2019-0034, Technical Requirements Manual Change Summary2019-10-18018 October 2019 Technical Requirements Manual Change Summary NRC 2019-0032, CFR 50.59 Evaluation and Commitment Change Summary Report2019-10-18018 October 2019 CFR 50.59 Evaluation and Commitment Change Summary Report NRC 2019-0036, Submittal of 2018 Update to Final Safety Analysis Report2019-10-18018 October 2019 Submittal of 2018 Update to Final Safety Analysis Report 2024-03-18
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NMC CommittedtoNuclearExcellene Point Beach Nuclear Plant Operated by Nuclear Management Company, LLC February 4, 2005 NRC 2005-0016 10 CFR 50.55a U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Point Beach Nuclear Plant, Units 1 and 2 Dockets 50-266 and 50-301 License Nos. DPR-24 and DPR-27 Relief Request from the Provisions of ASME Section Xl, IWA-4422.2.2, "Defect Removal Followed by Welding or Brazing," Relief Request 16 In accordance with 10 CFR 50.55a(a)(3)(ii), Nuclear Management Company, LLC (NMC), licensee for Point Beach Nuclear Plant (PBNP), hereby requests relief from the requirements of the 1998 Edition with Addenda through 2000 of Section Xl, IWA-4422.2.2, "Defect Removal Followed by Welding or Brazing," for PBNP Unit I and Unit 2. This request for relief is limited to three isolation valves in the Service Water (SW) system. The basis for the request is that compliance with the specified requirements is a hardship without a compensating increase in the level of quality and safety. Performing the specified examinations will require modification or removal of SW system valves.
During the NRC Safety System Design and Performance Capability Inspection conducted June 28 through July 16, 2004, the inspectors identified that 1SW-322, the HX-12A Component Cooling Water heat exchanger SW outlet isolation valve, was found to have cavitation pitting repaired by welding during a 1997 Repair/Replacement Activity. The review of this Repair/Replacement Activity showed that a magnetic particle or liquid penetrant examination required by Section XI was not performed prior to the weld repair of the pitting.
During the investigation of this incident, two additional SW valves were found to have the same issue: SW-315 and 2SW-307, the SW outlet isolation valves for Component Cooling Water heat exchangers HX-12C and HX-12D, respectively.
At the time of the Repair/Replacement Activities, PBNP was required to follow the 1986 Edition with no Addenda of Section Xl. The current Inservice Inspection interval is being conducted in accordance with the 1998 Edition of ASME Section XI with Addenda through 2000.
6590 Nuclear Road
- Two Rivers, Wisconsin 54241 Telephone: 920.755.2321
Document Control Desk Page 2 This letter contains no new commitments and no revisions to existing commitments.
Denni L oehll Site Vice-President, Poin Beach Nuclear Plant Nuclear Management Company, LLC Enclosure cc: Administrator, Region 111, USNRC Project Manager, Point Beach Nuclear Plant, USNRC Resident Inspector, Point Beach Nuclear Plant, USNRC Mike Verhagen, Department of Commerce, State of Wisconsin
Document Control Desk Page 3 bcc: A. Capristo D. E. Cooper H. J. Kocourek (OSRC)
D. L. Koehl F. D. Kuester (P460) K. M. Locke (2)
M. J. Lorek J. H. McCarthy G. C. Packard L. A. Schofield J. G. Schweitzer J. D. Shaw G. R. Sherwood R. L. Turner D. A. Weaver (P346)
File E. J. Weinkam III
', -.!; . .- I ENCLOSURE I RELIEF REQUEST 16 REQUEST FOR RELIEF FROM THE PROVISIONS OF ASME SECTION Xl, IWA-4422.2.2, "DEFECT REMOVAL FOLLOWED BY WELDING OR BRAZING" Pursuant to 10 CFR 50.55a(a)(3)(ii), Nuclear Management Company, LLC (NMC),
requests relief from the requirements of the 1998 Edition with Addenda through 2000 of Section Xl, IWA-4422.2.2, "Defect Removal Followed by Welding or Brazing," for Point Beach Nuclear Plant (PBNP) Unit 1 and Unit 2. This request for relief is limited to three isolation valves in the Service Water (SW) system. The basis for the request is that compliance with the specified requirements is a hardship without a compensating increase in the level of quality and safety.
- 1. ASME Code Components Affected Service Water Valve 1SW-322, Component Cooling Water Heat Exchanger IHX-12A SW Outlet Isolation Valve-Service Water Valve SW-315, Component Cooling Water Heat Exchanger HX-12C SW Outlet Isolation Valve Service Water Valve 2SW-307, Component Cooling Water Heat Exchanger 2HX-12D SW Outlet Isolation Valve
2. Applicable Code Edition and Addenda
1986 Edition of ASME Section XI, no Addenda, applied at the time of the initial repair (i.e., third ISI inspection interval).'
1998 Edition with Addenda through 2000 is the current applicable Code (i.e., fourth ISI inspection interval).
3. Applicable Code Requirement
Initial repair was performed per the 1986 Section XI Code:
IWD-4200, "Removal of Defects Including Preparations for Welding" (b)(1) After final grinding, the affected surfaces, including surfaces of cavities prepared for welding, shall be examined by the magnetic particle or liquid penetrant method to ensure that the indication has been reduced to an acceptable limit in accordance with IWA-3000...
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Current repair rules under 1998 Edition with Addenda through 2000 require:
IWA-4422.2.2, "Defect Removal Followed by Welding or Brazing" (a) Surface examination of the defect removal area is required prior to welding...
(b)The acceptance criteria of either the Construction Code or Section Xl shall be used for the excavation.
4. Reason for Request
During the 1997 repair of SW system valve 1SW-322, weld repairs were performed on the inside surface to restore the wall thickness of the valve due to cavitation erosion. A magnetic particle or liquid penetrant (surface) examination was not performed on the areas where grinding occurred prior to the weld buildup. The lack of the surface examination was discovered during the NRC Safety System Design and Performance Capability Inspection conducted June 28 through July 16, 2004, and was documented in the PBNP Corrective Action Program under CAP057711 and CAP057799.
During the investigation of this incident, two additional SW valves were noted as having weld repairs performed in a similar manner: SW-315 and 2SW-307, the SW outlet isolation valves for Component Cooling Water heat exchangers HX-12C and HX-12D, respectively. The weld repairs performed on valves SW-315 and 2SW-307 were intended to build up eroded areas caused by cavitation.
The 12-inch Component Cooling Water heat exchanger SW outlet isolation valves, 1SW-322, SW-315, and 2SW-307, have experienced cavitation pitting. The pitting is localized and concentrated in'the valve bodies downstream of the valve disks.
A significant pressure drop occurs across the valve disk since the downstream SW return header operates at a vacuum. It is believed that a major portion of the' existing pitting occurred in the first few years of plant operation when these large throttle valves were used for normal plant operations. After the first few years of plant operations, it was recognized there was potential for valve damage due to the long term, tight throttling application. Modification M-043 was implemented to install smaller bypass lines containing automatic Temperature Control Valves, bypassing the 12-inch throttle valves, for use during normal plant operation. Currently, the 12-inch valves are used only during RHR cooling operations, which are typically performed only during refueling outages.
The existing valves have been shown to be adequately performing their intended functions since 1997 as demonstrated by periodic ASME Section Xl pressure tests.
Performing the required examinations at this time will require additional repair or replacement of these SW system valves without a compensating increase in the level of quality and safety. To replace these valves, a full-core off-load is required.
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Replacement would be selected over grinding out the currently untested weld buildup material in these'evalves since the accuracy of removing all weld material cannot be guaranteed.-
Performing a repair or replacement activity when the valves are still adequately performing their pressure boundary function will not increase the safety margin of the plant.
- 5. Proposed Alternative and Basis for Use NMC proposes to use the existing valves as-is. If future Repair/Replacement activities are performed on these valves, the applicable Repair/Replacement rules of Section Xl will be followed.
The existing valves currently in place have been' shown to perform adequately.
There have been no through-wall leaks due to defects that may have been covered by the cavitation erosion welding'repair or due to new or existing defects.
Ultrasonic wall thickness scans are taken on these valves per Preventive Maintenance Work Orders after each refueling outage. The inspection results are tracked under the SW Inservice Inspection Program, which contains acceptance criteria for allowed minimum wall thicknesses. Engineering reviews the inspection results against the acceptance criteria and initiates corrective actions (i.e. repair or replacement) for the valves prior to any minimum wall thickness criteria being exceeded.
The ultrasonic measurements performed under the SW Inservice Inspection Program to date have given reasonable assurance that the cavitation erosion has not resulted in the valve walls falling below the minimum required thicknesses. In addition, the required Section XI periodic pressure testing has shown no through-wall leakage has occurred.
Replacement of the 'valves is a significant effort that would require core offload or installation of Temporary Modifications for alternate SW return lines from each of the Component Cooling Heat Exchangers.
Complying with the specified requirements by replacing the valves is a hardship' without a compensating increase in the level of quality and safety. Performing the specified examinations will require modification or removal of the SW system valves without a compensating increase in the level of quality and safety.
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- 6. Duration of Proposed Alternative The proposed duration of the relief request will be for the life of valves I SW-322, SW-315, and 2SW-307. If the valves are found to be deteriorating such that minimum wall thicknesses are being approached, or a defect is found at any other time, repair or replacement will be completed in accordance with the applicable rules of ASME Section XI.
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