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EPID:L-2021-LLR-0068, Proposed Alternative Requirements for the Repair of Reactor Vessel Head Penetrations for the 4th 10-Year Inservice Inspection Internal (VEGP-ISI-ALT-04-05, Version 1.0) (Approved, Closed) |
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Category:Code Relief or Alternative
MONTHYEARML23150A0802023-05-30030 May 2023 Acceptance Review - Vogtle Units 1 and 2 - Proposed LAR and Relief Request to Revise TS 3.4.14.1 and IST ALT-VR-02 (EPIDs L-2023-LLA-0061 and L-2023-LLR-0023) ML23095A2962023-04-14014 April 2023 Alternative Inspection Requirements for Steam Generator Nozzle to Reactor Coolant Pump Casing Welds (Vegp 3&4-Isi1- Alt-17) ML22259A1822022-09-22022 September 2022 Request for Proposed Inservice Testing Alternative ALT-VR-01 ML22118A0762022-05-13013 May 2022 Cover Letter for Vogtle Electric Generating Plant, Units 3 and 4 Request for Alternative Requirements for Inservice Test Interval Code Edition (VEGP 3&4-IST-ALT-01R2) ML22021A0012022-01-24024 January 2022 Relief Request for Proposed Alternative Requirements for the Repair of Reactor Vessel Head Penetrations for the Fourth 10-Year Inservice Inspection Interval, VEGP-ISI-ALT-04-05, Version 1.0 ML21154A2122021-06-0303 June 2021 Enclosure 1 - Vogtle Electric Generating Plant (VEGP) Unit 3 Proposed Alternative in Accordance with 10 CFR 50.55a(z)(1): Alternative Requirements for ASME Section III Remediation of Containment Vessel Unistrut Welding (VEGP 3-ALT-16) ML21154A2132021-06-0303 June 2021 Enclosure 2 - Vogtle Electric Generating Plant (VEGP) Unit 3 CB&I Procedure Qualification Record 14162(VEGP 3-ALT-16) ND-21-0392, Enclosure 3 - Vogtle Electric Generating Plant (VEGP) Unit 3 CB&I Procedure Qualification Record 14163 (VEGP 3-ALT-16)2021-06-0303 June 2021 Enclosure 3 - Vogtle Electric Generating Plant (VEGP) Unit 3 CB&I Procedure Qualification Record 14163 (VEGP 3-ALT-16) ML21040A1652021-02-0909 February 2021 (Vegp), Units 3 and 4, Revision to Proposed Alternative in Accordance with 10 CFR 50.55a(z)(2): Alternative Requirements for ASME Section XI Examination Coverage of Weldolet Branch Connection Welds ML20352A1552021-01-11011 January 2021 Proposed Relief Request for Alternative VEGP-ISI-ALT-04-04 to the Requirements of the ASME Code ML20307A1412020-11-12012 November 2020 Relief Request for Deferral of ASME Boiler and Pressure Vessel Code, Section XI, Required Summary Report Submittal NL-20-1262, Submission of Proposed Alternative to Submitting Vogtle Unit 2 Inservice Inspection Summary Report within 90 Days of Outage Completion2020-10-30030 October 2020 Submission of Proposed Alternative to Submitting Vogtle Unit 2 Inservice Inspection Summary Report within 90 Days of Outage Completion ML20216A3992020-08-0606 August 2020 Relief Request to Use a Provision of a Later Edition of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI ML20143A2332020-06-0303 June 2020 Relief Request for Deferral of ASME Boiler and Pressure Vessel Code, Section XI, Required Summary Report Submittal (EPID L-2020-LLR-0074 (COVID-19)) ML20132A1532020-05-14014 May 2020 ASME Code Alternative - May 14, 2020 Presubmittal Technical Exchange for Preservice Inspection (PSI) Alternative ML20034E8942020-02-11011 February 2020 Relief Request Gen-ISI-ALT-2019-01 for Proposed Alternative to Use of ASME Code Case N-831-1, Ultrasonic Examination in Lieu of Radiography for Welds in Ferritic or Austenitic Pipe Section XI, Division 1 ND-20-0083, Revision to Request for Alternative: Alternative Requirements for Inservice Test Interval Code Edition, Unit 4 (VEGP 3&4-IST-ALT-01R1)2020-02-0606 February 2020 Revision to Request for Alternative: Alternative Requirements for Inservice Test Interval Code Edition, Unit 4 (VEGP 3&4-IST-ALT-01R1) ND-19-1294, Request for Alternative: Alternative Requirements for Inservice Test Interval Code Edition, Unit 4 (VEGP 3&4-IST-ALT-01)2019-10-31031 October 2019 Request for Alternative: Alternative Requirements for Inservice Test Interval Code Edition, Unit 4 (VEGP 3&4-IST-ALT-01) ML18320A0192018-11-30030 November 2018 Relief Request Regarding Examination Coverage for Certain ASME Code Class 2 Category Welds (VEGP-ISI-RR-05) ML18296A7172018-10-31031 October 2018 Relief Request Regarding Examination Coverage for Certain Pressurizer and Steam Generator Welds (VEGP-ISI-RR-03) ND-18-1158, Revision to Request for Alternative: Alternative Requirements for Preservice Examination Volumetric Surface Configuration Requirements (VEGP 3&4-PSI/ISI-ALT-10R1)2018-08-30030 August 2018 Revision to Request for Alternative: Alternative Requirements for Preservice Examination Volumetric Surface Configuration Requirements (VEGP 3&4-PSI/ISI-ALT-10R1) NL-18-0428, Withdrawal of Proposed Alternative GEN-ISI-ALT-2017-001 Implementation of Code Case N-786-12018-04-0909 April 2018 Withdrawal of Proposed Alternative GEN-ISI-ALT-2017-001 Implementation of Code Case N-786-1 ML18054A0652018-03-0505 March 2018 Cover Letter - Vogtle Electric Generating Plant - Request for Alternative (ALT-9) ML17171A1022017-06-27027 June 2017 Inservice Inspection Alternative Regarding Category B-N-2 and B-N-3 Welds (VEGP ISI ALT 13) ML17061A2022017-03-17017 March 2017 Request for Alternative RR-PR-03 Regarding Nuclear Service Cooling Water Pump Instrument Accuracy ML17037D0502017-02-17017 February 2017 and 2; Request to Use Asme Code Case OMN-18 as an Alternative to Inservice Testing Requirements (CAC Nos. MF8188 and MF8189) NL-17-0101, Proposed Alternative VEGP-ISI-AL T-13 in Accordance with 10 CFR 50.55a(z)(2) to Extend B-N-2 and B-N-3 Inservice Inspection Examinations Schedule2017-01-26026 January 2017 Proposed Alternative VEGP-ISI-AL T-13 in Accordance with 10 CFR 50.55a(z)(2) to Extend B-N-2 and B-N-3 Inservice Inspection Examinations Schedule ML17006A1092017-01-26026 January 2017 Alternative to Inservice Inspection Regarding Reactor Pressure Vessel Threads Inflange Inspection ML16326A0442016-12-0808 December 2016 Alternative for Pump and Valve Inservice Testing Program ML16264A3212016-10-14014 October 2016 Alternatives for Pumps and Valves Inservice Testing Program ML14030A5702014-03-20020 March 2014 Request for Alternatives VEGP-ISI-ALT-06 ML13123A1602013-05-0707 May 2013 (VEGP) - Safety Evaluation of Relief Request VEGP-ISI-ALT-09, Version 2.0, Regarding Leakage Tests for Reactor Coolant Pressure Boundary Components ML13032A1062013-02-0707 February 2013 Safety Evaluation of Relief Request VEGP-ISI-ALT-08, Version 1, Regarding Installation of a Mechanical Clamp on a Class 1 Valve - Fourth 10-Year Interval ML1009001292010-06-11011 June 2010 Relief Requests VEGP-ISI-ALT-04 (Units 1 and 2) and VEGP-ISI-RR-01 (Unit 2) Inservice Inspection Alternatives for Third and Subsequent Inservice Inspection Intervals (TAC Nos. ME2226, ME2227, and ME1134) ML1012000882010-04-30030 April 2010 Acceptance of Vogtle Relief Request (VEGP-ISI-ALT-03) Dated April 7, 2010 NL-09-1410, VEGP-ISI-RR-01, Version 1.0, Relief Request in Accordance with 10 CFR 50.55a(g)(5)(iii)2009-09-0909 September 2009 VEGP-ISI-RR-01, Version 1.0, Relief Request in Accordance with 10 CFR 50.55a(g)(5)(iii) ML0731004352007-11-15015 November 2007 Third 10-Year Interval, Inservice Program Relief Request RR-V-1 (Tac Nos. MD5409 and MD5410) ML0627703592006-09-29029 September 2006 Evaluation of Relief Request ISI-GEN-ALT-06-02 NL-06-1713, Proposed Alternative for Application of Pressurizer Nozzle Full-Structural Weld Overlays2006-08-10010 August 2006 Proposed Alternative for Application of Pressurizer Nozzle Full-Structural Weld Overlays ML0510301992005-04-25025 April 2005 RR, ISI Program Intervals for Alternative Alignment of Iwe/Iwl Inspection Program (Tac No. MC4870, MC4871, MC4872, MC4873, MC4874, MC4875) ML0332800372003-11-21021 November 2003 Safety Evaluation Re. Request to Use ASME Code Case N-661 ML0225904572002-09-16016 September 2002 Code Relief, Relief Request for the Second Ten-Year Interval Inservice Testing Program 2023-05-30
[Table view] Category:Letter
MONTHYEARML24032A0252024-02-0505 February 2024 NRC Initial Test Program and Operational Programs Integrated Inspection Report 05200026-2023009 ML24010A0712024-01-31031 January 2024 Exemption from Select Requirements of 10 CFR Part 73 (Security Notifications, Reports and Recordkeeping and Suspicious Activity Reporting) ML24031A6102024-01-31031 January 2024 Cyber Security Inspection Report 05200026/2024401 - Public ML24029A0592024-01-30030 January 2024 Request for Withholding Information from Public Disclosure Responses to NRC Request for Additional Information for Refueling Outage 1R24 Steam Generator Tube Inspection Report Enclosure 2, GAE-NRCD-RF-LR-000002 P-Attachment, Rev. 0 ML24016A1132024-01-30030 January 2024 Correction of Unit 1 Amendment Nos. 96 and 190 and Unit 2 Amendment Nos. 74 and 173 Adoption of Standard Technical Specifications Westinghouse Plants NL-24-0031, Inservice Inspection Program Owner'S Activity Report (OAR-1) for Outage 2R232024-01-29029 January 2024 Inservice Inspection Program Owner'S Activity Report (OAR-1) for Outage 2R23 IR 05000424/20244032024-01-26026 January 2024 Information Request for the Cyber-Security Baseline Inspection, Notification to Perform Inspection 05000424/2024403; 05000425/2024403 NL-24-0020, Plan, Unit 1 Responses to NRC Request for Additional Information for Refueling Outage 1R24 Steam Generator Tube Inspection Report2024-01-22022 January 2024 Plan, Unit 1 Responses to NRC Request for Additional Information for Refueling Outage 1R24 Steam Generator Tube Inspection Report ML23347A2092024-01-17017 January 2024 Voluntary Requests for Data, Information, And/Or Observation ML23279A0042024-01-17017 January 2024 Amendment No. 194 to Remove Combined License Appendix C NL-23-0926, Correction of Technical Specification Typographical Error2024-01-12012 January 2024 Correction of Technical Specification Typographical Error ML23341A2042024-01-12012 January 2024 Request for Additional Information Exemption Requests for Physical Barriers (EPID L-2023-LLE-0018 & L-2023-LLE-0021) ML23345A1312024-01-0303 January 2024 Withholding Letter - SNC Fleet - Physical Barriers Exemption (L-2023-LLE-0018 and L-2023-LLE-0021) ML23317A2072023-12-22022 December 2023 Issuance of Amendments 223 and 206 Regarding Revision to Technical Specifications to Adopt TSTF-339-A, Relocate Technical Specification Parameters to the COLR Consistent with WCAP-1448 ML23335A1222023-12-19019 December 2023 Safety Evaluation Regarding Implementation of Mitigating Strategies Related to Order EA-12-049 (EPID L-2023-LRQ-0002) - Letter ML23353A1702023-12-19019 December 2023 LAR-22-002, TS 3.8.3 Inverters Operating Completion Time Extension Letter ML23310A2922023-12-0707 December 2023 Issuance of Amendment for Exception to Regulatory Guide 1.163, LAR 23 007 ML23339A1812023-12-0707 December 2023 Correction Letter Regarding License Amendment Request: More Restrictive Action for Technical Specification 3.1.9 ML23338A2182023-12-0606 December 2023 Project Manager Reassignment NL-23-0878, Request for Exemption from Security Event Notification Implementation2023-11-29029 November 2023 Request for Exemption from Security Event Notification Implementation ML23289A1632023-11-28028 November 2023 Letter and Amendment 195 and 192 LAR-23-006R1 TS 3.1.9 More Restrictive Action NL-23-0827, Response to Requests for Additional Information for a License Amendment Request and a Proposed Alternative Related to TS 3.4.142023-11-17017 November 2023 Response to Requests for Additional Information for a License Amendment Request and a Proposed Alternative Related to TS 3.4.14 ML23318A4582023-11-14014 November 2023 Integrated Inspection Report 05200025/2023003 ML23312A3502023-11-14014 November 2023 Integrated Inspection Report 05200026/2023003 ML23306A3552023-11-0808 November 2023 NRC Initial Test Program and Operational Programs Integrated Inspection Report 052000/262023008 ML23268A0572023-11-0707 November 2023 Issuance of Amendments 194 & 191 Request for License Amendment Relocation of Technical Specification 3.7.9, Spent Fuel Pool Makeup Water Sources (LAR-23-003) IR 05000424/20234022023-11-0606 November 2023 Security Baseline Inspection Report 05000424/2023402 and 05000425/2023402 IR 05000424/20230032023-10-27027 October 2023 Integrated Inspection Report 05000424/2023003 and 05000425/2023003 ML23291A1512023-10-18018 October 2023 Information Request for the Cyber Security Baseline Inspection, Notification to Perform Inspection 0520026/2024401 ML23263A9852023-10-12012 October 2023 Issuance of Amendments Nos. 221 and 204, Regarding Technical Specification 5.5.11.C, Acceptance Criteria for Charcoal Filter Testing ML23283A0472023-10-0808 October 2023 Neop Letter Dated October 8, 2023 - Vogtle 3 & 4 - TS 3.7.6 License Amendment Request NL-23-0750, Response to Second Request for Additional Information Regarding License Amendment Request: Technical Specification Revision to Adopt TSTF-339-A, Relocate Technical Specification Parameters to the Colr2023-10-0404 October 2023 Response to Second Request for Additional Information Regarding License Amendment Request: Technical Specification Revision to Adopt TSTF-339-A, Relocate Technical Specification Parameters to the Colr NL-23-0745, Refueling Outage 1R24 Steam Generator Tube Inspection Report2023-09-22022 September 2023 Refueling Outage 1R24 Steam Generator Tube Inspection Report ML23254A2032023-09-13013 September 2023 Initial Test Program and Operational Programs Inspection Report 05200025/2023013 ML23241B0212023-09-12012 September 2023 Review of Quality Assurance Topical Report ML23234A2352023-09-0808 September 2023 Request for Withholding Information from Public Disclosure Notification of Full Compliance of Required Action for NRC Order EA-12-049 Mitigation Strategies for Beyond-Design-Basis External Events IR 05000424/20230912023-09-0505 September 2023 Plan Units 1 and 2 - NRC Investigation Report 2-2022-006 and Notice of Violation - NRC Inspection Report 05000424/2023091 and 05000425/2023091 ML23234A3002023-09-0101 September 2023 NRC Integrated Inspection Report 05200026/2023003 ML23243A0092023-08-31031 August 2023 Updated Inspection Plan for Vogtle Electric Generating Plant, Units 3 & 4 (Report 05200025 2023005 & 05200026 2023005) NL-23-0695, Response to Round 2 Request for Additional Information Regarding License Amendment Request for Technical Specification 3.8.3, Inverters Operating, Completion Time Extension (LAR-22-002S2)2023-08-31031 August 2023 Response to Round 2 Request for Additional Information Regarding License Amendment Request for Technical Specification 3.8.3, Inverters Operating, Completion Time Extension (LAR-22-002S2) ML23243B0252023-08-30030 August 2023 Exam Corporate Notification Letter (210 Day) IR 05000424/20230052023-08-29029 August 2023 Updated Inspection Plan for Vogtle Electric Generating Plant, Units 1 & 2 - Report 05000424/2023005 and 05000425/2023005 NL-23-0666, License Amendment Request: Remove Combined License Appendix C (LAR 23-008)2023-08-28028 August 2023 License Amendment Request: Remove Combined License Appendix C (LAR 23-008) 2024-02-05
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January 24, 2022 Ms. Cheryl A. Gayheart Regulatory Affairs Director Southern Nuclear Operating Co., Inc.
3535 Colonnade Parkway Birmingham, AL 35243
SUBJECT:
VOGTLE ELECTRIC GENERATING PLANT, UNITS 1 AND 2 - RELIEF REQUEST FOR PROPOSED ALTERNATIVE REQUIREMENTS FOR THE REPAIR OF REACTOR VESSEL HEAD PENETRATIONS FOR THE FOURTH 10-YEAR INSERVICE INSPECTION INTERVAL, VEGP-ISI-ALT-04-05, VERSION 1.0 (EPID: L-2021-LLR-0068)
Dear Ms. Gayheart:
By letter dated September 10, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21256A243), Southern Nuclear Operating Company (SNC, the licensee) submitted a proposed alternative VEGP-ISI-ALT-04-05, Version 1.0, for the repair of degraded reactor vessel head penetrations at Vogtle Electric Generating Plant (Vogtle), Units 1 and 2. In order to repair a degraded penetration J-groove weld, the licensee proposed to use the embedded flaw repair process described in the U.S. Nuclear Regulatory (NRC)-approved WCAP-15987-P, Revision 2-P-A report (ADAMS Accession No. ML040290233) and WCAP-18647-P, Revision 0, Technical Basis for Westinghouse Embedded Flaw Repair of Vogtle Units 1 and 2, Reactor Vessel Head Penetrations, enclosed in the submittal dated September 10, 2021.
The NRC staff has determined that the proposed alternative in SNCs request would provide an acceptable level of quality and safety. The NRC staff has concluded that the licensee has adequately addressed the regulatory requirements set forth in Title 10 of the Code of Federal Regulations, Section 50.55a(z)(1). The NRC staff authorizes the use of proposed alternative VEGP-ISI-ALT-04-05 at Vogtle, Units 1 and 2, through the end of the fourth 10-year Inservice Inspection Interval ending May 30, 2027.
All other American Society of Mechanical Engineers Boiler and Pressure Vessel Code,Section XI, requirements for which an alternative was not specifically requested and approved in this proposed alternative remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.
C. A. Gayheart If you have any questions, please contact the Senior Project Manager, John G. Lamb, at (301) 415-3100 or via email at John.Lamb@nrc.gov.
Sincerely, Michael T. Digitally signed by Michael T. Markley Markley Date: 2022.01.24 07:46:56 -05'00' Michael T. Markley, Chief Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-424 and 50-425 cc: Listserv
VOGTLE ELECTRIC GENERATING PLANT, UNITS 1 AND 2 - APPROVAL OF REQUEST FOR ALTERNATIVE VEGP-ISI-ALT-04-05 FROM CERTAIN REQUIREMENTS OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS BOILER AND PRESSURE VESSEL CODE (EPID L-2021-LLR-0068)
LICENSEE INFORMATION Licensee: Southern Nuclear Operating Company (SNC)
Plant Name and Units: Vogtle Electric Generating Plant (Vogtle), Units 1 and 2 Docket Nos.: 50-424, 50-425 APPLICATION INFORMATION Submittal Date: September 10, 2021 Submittal Agencywide Documents Access and Management System (ADAMS) Accession No.: ML21256A243 Supplement Date(s): N/A Supplement ADAMS Accession No.: N/A Licensee Proposed Alternative No. or Identifier: VEGP-ISI-ALT-04-05 Applicable Regulation: Title 10 of the Code of Federal Regulations (10 CFR),
Section 50.55a(z)(1)
Applicable Code Requirements: American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code)Section XI Rules for Inservice Inspection of Nuclear Power Plant Components Article IWA-4000 contains requirements for the removal of defects from and welded repairs performed on ASME components.
ASME Code Section XI, IWA-4411 requires that Welding, brazing, fabrication, and installation shall be performed in accordance with the Owner's Requirements and, except as modified below, in accordance with the Construction Code of the item.
ASME Code,Section III Rules for Construction of Nuclear Facility Components, Paragraph NB-4131 requires that the defects are eliminated, repaired, and examined in accordance with Subarticle NB-2500, which requires removal of defects via grinding or machining.
Applicable Code Edition and Addenda: The construction Code for Vogtle 1 and 2 is ASME Code,Section III, 1971 Edition through Summer 72 Addenda. The inservice inspection (ISI) code of record for the fourth 10-year interval at Vogtle Units 1 and 2 is ASME code Section XI 2007 Edition, through 2008 Addenda Brief Description of the Proposed Alternative: The licensee is proposing to use an embedded flaw repair (EFR) method for its Vessel Head Penetrations (VHP) and associated J-groove attachment welds as an alternative to the defect removal requirements of ASME Code Section XI and Section III. The proposed embedded flaw repair method is based on WCAP-15987-P, Revision 2-P-A.
REGULATORY EVALUATION Regulatory Basis: 10 CFR 50.55a(z)(1)
Adherence to Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (B&PV Code) is mandated by 10 CFR 50.55a(g)(4), which states, in part, that ASME B&PV Code Class 1, 2, and 3 components will meet the requirements, except the design and access provisions and the pre-service examination requirements, set forth in the ASME B&PV Code,Section XI.
Paragraph 10 CFR 50.55a(z) states, in part, that alternatives to the requirements of 10 CFR 50.55a(b)-(h) may be used, when authorized by the Director, Office of Nuclear Reactor Regulation, if (1) the proposed alternatives would provide an acceptable level of quality and safety or (2) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
TECHNICAL EVALUATION The licensee requested authorization of its alternative Relief Request VEGP-ISI-ALT-04-05 under 10 CFR 50.55a(z)(1) on the basis that the proposed alternative requirements for repair of VHP's provides an acceptable level of quality and safety.
The purpose of the licensees proposed repair is to address primary water stress corrosion cracking (PWSCC), which typically initiates in susceptible materials, such as Alloy 600 material and Alloy 82/182 weld materials, in areas of tensile stress and certain environmental conditions, such as higher temperatures and primary coolant water environments. The reactor VHPs and their associated J-groove attachment welds at Vogtle, Unit 1 and 2, meet these conditions to be susceptible to PWSCC. The proposed repair technique, the EFR, isolates the susceptible material using a seal weld of Alloy 52 or 52M weld material, which is less susceptible to PWSCC crack initiation and growth.
The proposed EFR method is based on U.S. Nuclear Regulatory Commission (NRC) approved Westinghouse Topical Report, Technical Basis for the Embedded Flaw Process for Repair of Reactor Vessel Head Penetrations, WCAP-15987-P, Revision 2-P-A. The repair methods for an axial or circumferential flaw fall into four main categories, inner diameter (ID) repairs in the VHP, outer diameter (OD) repairs below the J-groove weld, OD repairs of the VHP of a flaw that extends to the J-groove weld and outer diameter repairs of the J-groove weld itself.
The licensees proposed repair methodology differs from WCAP-15987 Revision 2-P-A in three areas. First, the minimum number of Alloy 52 weld layers applied on the ID or OD of the VHP is changed from three to two layers; second, the allowance of the repair for ID circumferential flaws; and third, the allowance for the licensee to remove and reweld part of the flaw in the J-groove weld OD surface prior to applying the seal weld. The NRC staff has reviewed these changes in other licensee proposed alternatives to use the EFR and found them acceptable.
The NRC staff found the use of two layers instead of three for the ID repair of the VHP allows for less grinding on the nozzle, and, therefore less damage to the VHP and lower worker radiation dose. This along with the PWSCC resistance of the seal weld materials and the effectiveness of the non-destructive examination (NDE) requirements for volumetric or surface examinations for ISI, gives the NRC staff confidence that two layers of the seal weld are acceptable on the VHP ID or OD surface. The NRC staff considers the repair of circumferential flaws initiating from the ID surface to be j adequately addressed by the EFR technique in comparison to axial flaws given the PWSCC crack resistance of the Alloy 52 or 52M seal weld material and the ISI NDE requirements. The NRC staff also agrees that the excavation of part of the indication in the J-groove weld can be performed safely in accordance with Section 2.c of the licensees proposed alternative to refill the excavated area with Alloy 52 or 52M material.
Therefore, the NRC staff found SNCs proposed repair technique was consistent with the approved methodology of WCAP-15987 Revision 2-P-A with the above three noted deviations that the NRC considers acceptable. Based on the above, the NRC finds that the licensee has provided reasonable assurance of structural integrity.
The licensee also proposed differences from WCAP-15987-P, Revision 2-P-A for the NDE requirements of Table 1 of the conditions described in the NRC Safety Evaluation on WCAP 15987-P, Revision 2-P dated July 3, 2003 (ADAMS Accession No. ML031840237).
These differences were mainly to the change of VHP examination requirements to 10 CFR 50.55a(g)(6)(ii)(D) since the WCAP was approved.
Flaw Repair ISI NDE of the Repair Location Repair NDE Orientation Weld Repair Note 2 VHP Nozzle ID Axial or UT (ultrasonic testing)
Seal UT or Surface (inside diameter) Circumferential and Surface VHP Nozzle OD Axial or Note 1 Note 1 Note 1 (outside Circumferential diameter) above j-groove weld VHP Nozzle OD Axial or UT or Surface UT or Surface below j-groove Circumferential Seal weld UT and Surface, J-groove weld Axial Seal UT and Surface, Note 3 Notes 3 and 4 UT and Surface, J-groove weld Circumferential Seal UT and Surface, Note 3 Notes 3 and 4 Notes: (1) Repair method, if required, must be approved separately by the NRC.
(2) Preservice and inservice inspection to be consistent with 10 CFR 50.55a(g)(6)(ii)(D), which requires the implementation of Code Case N-729-6 with conditions; or NRC approved alternatives to these specified conditions.
(3) UT personnel and procedures qualified in accordance with 10 CFR 10.55a(g)(6)(ii)(D), which requires the implementation of Code Case N-729-6 with conditions. Examine the accessible portion of the J-groove repaired region. The UT plus surface examination coverage equals to 100 percent.
(4) Surface examination of the embedded flaw repair (EFR) shall be performed to ensure the repair satisfies ASME Code Section III, NB-5350, acceptance standards. The frequency of examination shall be as follows:
- a. Perform surface examination during the first and second refueling outage after installation or repair of the EFR.
- b. When the examination results of 4.a verify acceptable results, then reinspection of the embedded flaw repair will be continued at a frequency of every other refueling outage. If these examinations identify unacceptable results that require flaw removal, flaw reduction to acceptable dimensions, or welded repair, the requirements of 4.a above shall be applied during the next refueling outage.
The NRC staff notes these NDE alternatives for the EFR process repaired VHP and associated J-groove welds have been approved previously for other licensees and are consistent with the prior precedents. The examination requirements of 10 CFR 50.55a(g)(6)(ii)(D) provide the latest NRC regulatory guidance for qualification and acceptance of the NDE methods identified.
Further, the NRC staff finds that the frequency of NDE required above provides reasonable assurance of structural integrity of the VHP and associated J-groove welds given the EFR process.
Based on the above, the NRC staff concludes that SNCs proposed alternative provides reasonable assurance of an acceptable level of quality and safety for the use of EFR process on VHP nozzles and its associated J-groove welds at Vogtle, Units 1 and 2, as required by 10 CFR 50.55a(z)(1).
CONCLUSION The NRC staff has determined that the proposed alternative in SNCs request referenced above would provide an acceptable level of quality and safety. The NRC staff concludes that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(1).
The NRC staff authorizes the use of proposed alternative VEGP-ISI-ALT-04-05 at Vogtle, Units 1 and 2, through the end of the fourth 10-year Inservice Inspection Interval ending May 30, 2027.
All other ASME BPV Code,Section XI, requirements for which an alternative was not specifically requested and approved in this proposed alternative remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.
Principal Contributor: Jay Collins, NRR Date: January 24, 2022
ML22021A009 OFFICE DORL/LPL2-1/PM DORL/LPL2-1/LA DNRL/NPHP/BC DORL/LPL2-1/BC NAME JLamb KGoldstein SCumblidge (A) MMarkley DATE 01/20/2022 01/21/2022 01/20/2022 01/24/2022