Letter Sequence Response to RAI |
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EPID:L-2022-SLR-0000, Application for Subsequent License Renewal Appendix E - Applicants Environmental Report (Open) |
Initiation
- Request, Request, Request, Request, Request, Request
- Acceptance...
- Supplement, Supplement, Supplement, Supplement, Supplement, Supplement, Supplement, Supplement
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MONTHYEARML23009A3532023-01-0909 January 2023 Docket No. 50-263, Renewal License Numbers DPR-22 Application for Subsequent Renewal Operating License Project stage: Request L-MT-23-001, Application for Subsequent License Renewal Appendix E - Applicants Environmental Report2023-01-0909 January 2023 Application for Subsequent License Renewal Appendix E - Applicants Environmental Report Project stage: Request ML23009A3542023-01-0909 January 2023 Subsequent License Renewal Application Sections 1 - 4 and Appendices a - D Project stage: Other L-MT-23-010, Subsequent License Renewal Application Supplement 12023-04-0303 April 2023 Subsequent License Renewal Application Supplement 1 Project stage: Supplement ML23214A2422023-05-25025 May 2023 Breakout Questions - Aging Management Audit - Monticello Unit 1 - Subsequent License Renewal Application Project stage: Other ML23214A2322023-05-25025 May 2023, 31 August 2023 Aging Management Audit - Monticello Unit 1 - Subsequent License Renewal Application Project stage: Request L-MT-23-025, Subsequent License Renewal Application Supplement 22023-06-26026 June 2023 Subsequent License Renewal Application Supplement 2 Project stage: Supplement L-MT-23-030, Subsequent License Renewal Application Supplement 32023-07-0404 July 2023 Subsequent License Renewal Application Supplement 3 Project stage: Supplement L-MT-23-031, Subsequent License Renewal Application Supplement 4 and Responses to Request for Confirmation of Information - Set 12023-07-18018 July 2023 Subsequent License Renewal Application Supplement 4 and Responses to Request for Confirmation of Information - Set 1 Project stage: Supplement L-MT-23-034, Subsequent License Renewal Application Response to Request for Additional Information Set 12023-08-15015 August 2023 Subsequent License Renewal Application Response to Request for Additional Information Set 1 Project stage: Response to RAI L-MT-23-035, Subsequent License Renewal Application Supplement 52023-08-28028 August 2023 Subsequent License Renewal Application Supplement 5 Project stage: Supplement ML23214A2412023-08-31031 August 2023 Letter: Aging Management Audit - Monticello Unit 1 - Subsequent License Renewal Application Project stage: Other L-MT-23-036, Subsequent License Renewal Application Response to Request for Additional Information Set 2 and Supplement 62023-09-0505 September 2023 Subsequent License Renewal Application Response to Request for Additional Information Set 2 and Supplement 6 Project stage: Supplement ML23268A0172023-09-20020 September 2023, 25 September 2023 SLRA - Requests for Confirmation of Information - Set 2 Project stage: Request L-MT-23-037, Subsequent License Renewal Application Response to Request for Additional Information Set 32023-09-22022 September 2023 Subsequent License Renewal Application Response to Request for Additional Information Set 3 Project stage: Response to RAI L-MT-23-041, Subsequent License Renewal Application Response to Request for Confirmation of Information Set 22023-10-0303 October 2023 Subsequent License Renewal Application Response to Request for Confirmation of Information Set 2 Project stage: Request L-MT-23-046, Subsequent License Renewal Application Response to Request for Additional Information Round 2 - Set 12023-11-0909 November 2023 Subsequent License Renewal Application Response to Request for Additional Information Round 2 - Set 1 Project stage: Response to RAI L-MT-23-052, Subsequent License Renewal Application Supplement 72023-11-30030 November 2023 Subsequent License Renewal Application Supplement 7 Project stage: Supplement ML23332A1652023-11-30030 November 2023 Second Limited Aging Management Audit Plan Regarding the Subsequent License Renewal Application Review Project stage: Other L-MT-23-054, Subsequent License Renewal Application Supplement 82024-01-11011 January 2024 Subsequent License Renewal Application Supplement 8 Project stage: Supplement ML24047A0922024-02-26026 February 2024 Limited-Scope Audit Report for Buried Piping and External Surfaces AMPs Project stage: Other ML24054A1582024-02-27027 February 2024 – Limited Aging Management Audit Report Regarding the Subsequent License Renewal Application Review Project stage: Other ML24068A0122024-03-18018 March 2024 SLRA Safety Evaluation and Transmittal Letter Project stage: Request ML24068A0132024-03-18018 March 2024 Transmittal Letter for Monticello SE for SLRA Review Project stage: Other 2023-08-15
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Category:Letter type:L
MONTHYEARL-MT-24-038, Subsequent License Renewal Application Response to Request for Additional Information - 3rd Round RAI2024-10-15015 October 2024 Subsequent License Renewal Application Response to Request for Additional Information - 3rd Round RAI L-MT-24-025, Application to Revise Technical Specifications to Adopt TSTF-554, Revise Reactor Coolant Leakage Requirements2024-09-26026 September 2024 Application to Revise Technical Specifications to Adopt TSTF-554, Revise Reactor Coolant Leakage Requirements L-MT-24-029, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information-Supplement to Set 1 Part 2 and Response to 2ci Round RAI2024-09-13013 September 2024 Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information-Supplement to Set 1 Part 2 and Response to 2ci Round RAI L-MT-24-028, Response to RCI for RR-017 ISI Impracticality2024-08-28028 August 2024 Response to RCI for RR-017 ISI Impracticality L-MT-24-022, – Preparation and Scheduling of Operator Licensing Examinations2024-07-0909 July 2024 – Preparation and Scheduling of Operator Licensing Examinations L-MT-24-019, Submittal of ASME Section XI, Section IWB-3720 Analytical Evaluation in Accordance with 10 CFR 50.55a(b)(2)(xliii)2024-06-10010 June 2024 Submittal of ASME Section XI, Section IWB-3720 Analytical Evaluation in Accordance with 10 CFR 50.55a(b)(2)(xliii) L-MT-24-017, Response to Request for Additional Information Regarding License Amendment Request to Revise Monticello Technical Specification Surveillance Requirement 3.8.6.6 (EPID-L-2023-LLA-01602024-06-0404 June 2024 Response to Request for Additional Information Regarding License Amendment Request to Revise Monticello Technical Specification Surveillance Requirement 3.8.6.6 (EPID-L-2023-LLA-0160 L-MT-24-015, Response to Request for Additional Information - Alternative Request VR-09 for OMN-172024-05-16016 May 2024 Response to Request for Additional Information - Alternative Request VR-09 for OMN-17 L-MT-24-013, 2023 Annual Radiological Environmental Operating Report2024-05-14014 May 2024 2023 Annual Radiological Environmental Operating Report L-MT-24-016, 2023 Annual Report of Individual Monitoring for the Monticello Nuclear Generating Plant (MNGP)2024-05-0808 May 2024 2023 Annual Report of Individual Monitoring for the Monticello Nuclear Generating Plant (MNGP) L-MT-24-002, Submittal of Revision 41 to the Updated Safety Analysis Report2024-04-17017 April 2024 Submittal of Revision 41 to the Updated Safety Analysis Report L-MT-24-004, Submittal of 10 CFR 72.48 Report for Monticello Nuclear Generating Plant (MNGP)2024-04-17017 April 2024 Submittal of 10 CFR 72.48 Report for Monticello Nuclear Generating Plant (MNGP) L-MT-24-006, Subsequent License Renewal Application Annual Update 1 and Supplement 92024-02-29029 February 2024 Subsequent License Renewal Application Annual Update 1 and Supplement 9 L-MT-24-007, Response to NRC Request for Additional Information on Proposed Inservice Inspection Alternative RR-002 for the Sixth Ten-Year ISI Interval2024-02-15015 February 2024 Response to NRC Request for Additional Information on Proposed Inservice Inspection Alternative RR-002 for the Sixth Ten-Year ISI Interval L-MT-24-001, 10 CFR 50.55a Request RR-017 - Inservice Inspection (ISI) Impracticality in Accordance with 10 CFR 50.55a(g)(5)(iii) During the Fifth Ten-Year Interval2024-01-30030 January 2024 10 CFR 50.55a Request RR-017 - Inservice Inspection (ISI) Impracticality in Accordance with 10 CFR 50.55a(g)(5)(iii) During the Fifth Ten-Year Interval L-MT-23-054, Subsequent License Renewal Application Supplement 82024-01-11011 January 2024 Subsequent License Renewal Application Supplement 8 L-MT-23-047, License Amendment Request: Revision to the MNGP Pressure Temperature Limits Report to Change the Neutron Fluence Methodology and Incorporate New Surveillance Capsule Data2023-12-29029 December 2023 License Amendment Request: Revision to the MNGP Pressure Temperature Limits Report to Change the Neutron Fluence Methodology and Incorporate New Surveillance Capsule Data L-MT-23-056, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 1 Part 22023-12-18018 December 2023 Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 1 Part 2 L-MT-23-042, 2023 Annual Report of Changes in Emergency Core Cooling System Evaluation Models Pursuant to 10 CFR 50.462023-12-11011 December 2023 2023 Annual Report of Changes in Emergency Core Cooling System Evaluation Models Pursuant to 10 CFR 50.46 L-MT-23-053, Condition Prohibited by Technical Specifications Due to Inoperable Main Steam Line Low Pressure Isolation Switch2023-12-0404 December 2023 Condition Prohibited by Technical Specifications Due to Inoperable Main Steam Line Low Pressure Isolation Switch L-MT-23-052, Subsequent License Renewal Application Supplement 72023-11-30030 November 2023 Subsequent License Renewal Application Supplement 7 L-MT-23-051, Update to the Technical Specification Bases2023-11-28028 November 2023 Update to the Technical Specification Bases L-MT-23-049, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 12023-11-21021 November 2023 Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 1 L-MT-23-043, 10 CFR 50.55a(z)(1) Request Regarding OMN-17, Revision 1. VR-092023-11-13013 November 2023 10 CFR 50.55a(z)(1) Request Regarding OMN-17, Revision 1. VR-09 L-MT-23-038, License Amendment Request to Revise Monticello Technical Specification Surveillance Requirement 3.8.6.62023-11-10010 November 2023 License Amendment Request to Revise Monticello Technical Specification Surveillance Requirement 3.8.6.6 L-MT-23-046, Subsequent License Renewal Application Response to Request for Additional Information Round 2 - Set 12023-11-0909 November 2023 Subsequent License Renewal Application Response to Request for Additional Information Round 2 - Set 1 L-MT-23-041, Subsequent License Renewal Application Response to Request for Confirmation of Information Set 22023-10-0303 October 2023 Subsequent License Renewal Application Response to Request for Confirmation of Information Set 2 L-MT-23-037, Subsequent License Renewal Application Response to Request for Additional Information Set 32023-09-22022 September 2023 Subsequent License Renewal Application Response to Request for Additional Information Set 3 L-MT-23-036, Subsequent License Renewal Application Response to Request for Additional Information Set 2 and Supplement 62023-09-0505 September 2023 Subsequent License Renewal Application Response to Request for Additional Information Set 2 and Supplement 6 L-MT-23-035, Subsequent License Renewal Application Supplement 52023-08-28028 August 2023 Subsequent License Renewal Application Supplement 5 L-MT-23-034, Subsequent License Renewal Application Response to Request for Additional Information Set 12023-08-15015 August 2023 Subsequent License Renewal Application Response to Request for Additional Information Set 1 L-MT-23-032, 10 CFR 50.55a(z)(2) Request Regarding MO-2397, VR-112023-07-31031 July 2023 10 CFR 50.55a(z)(2) Request Regarding MO-2397, VR-11 L-MT-23-028, 2023 Refueling Outage 90-Day Inservice Inspection (ISI) Summary Report2023-07-31031 July 2023 2023 Refueling Outage 90-Day Inservice Inspection (ISI) Summary Report L-MT-23-031, Subsequent License Renewal Application Supplement 4 and Responses to Request for Confirmation of Information - Set 12023-07-18018 July 2023 Subsequent License Renewal Application Supplement 4 and Responses to Request for Confirmation of Information - Set 1 L-MT-23-030, Subsequent License Renewal Application Supplement 32023-07-0404 July 2023 Subsequent License Renewal Application Supplement 3 L-MT-23-025, Subsequent License Renewal Application Supplement 22023-06-26026 June 2023 Subsequent License Renewal Application Supplement 2 L-MT-23-019, Submittal of 2022 Annual Radiological Environmental Operating Report2023-05-10010 May 2023 Submittal of 2022 Annual Radiological Environmental Operating Report L-MT-23-020, Submittal of 2022 Annual Radioactive Effluent Release Report2023-05-10010 May 2023 Submittal of 2022 Annual Radioactive Effluent Release Report L-MT-23-021, Core Operating Limits Report (COLR) for the Monticello Nuclear Generating Plant for Cycle 322023-05-0202 May 2023 Core Operating Limits Report (COLR) for the Monticello Nuclear Generating Plant for Cycle 32 L-MT-23-017, 2022 Annual Report of Individual Monitoring for the Monticello Nuclear Generating Plant (MNGP)2023-04-18018 April 2023 2022 Annual Report of Individual Monitoring for the Monticello Nuclear Generating Plant (MNGP) L-MT-23-010, Subsequent License Renewal Application Supplement 12023-04-0303 April 2023 Subsequent License Renewal Application Supplement 1 L-MT-23-013, Core Operating Limits Report (COLR) for Cycle 31, Revision 32023-03-28028 March 2023 Core Operating Limits Report (COLR) for Cycle 31, Revision 3 L-MT-23-012, Core Operating Limits Report (COLR) for Monticello Nuclear Generating Plant Cycle 31, Revision 22023-03-17017 March 2023 Core Operating Limits Report (COLR) for Monticello Nuclear Generating Plant Cycle 31, Revision 2 L-MT-23-008, 10CFR50.55a Request to Use Later Edition of ASME Section XI for ISI Code of Record (RR-003)2023-02-0707 February 2023 10CFR50.55a Request to Use Later Edition of ASME Section XI for ISI Code of Record (RR-003) L-MT-23-004, CFR 50.55a Request RR-001, Request to Use a Provision of a Later Edition of the ASME Boiler and Pressure Vessel Code, Section XI for the Monticello Third Interval Containment Inservice Inspection Program2023-01-23023 January 2023 CFR 50.55a Request RR-001, Request to Use a Provision of a Later Edition of the ASME Boiler and Pressure Vessel Code, Section XI for the Monticello Third Interval Containment Inservice Inspection Program L-MT-23-005, Response to the NRC Request for Additional Information Regarding the 50.55a Request Pr 08, HPCI Pump Quarterly Testing (EPID Number L-2022-LLR-0088)2023-01-0606 January 2023 Response to the NRC Request for Additional Information Regarding the 50.55a Request Pr 08, HPCI Pump Quarterly Testing (EPID Number L-2022-LLR-0088) L-MT-22-049, Industry Groundwater Protection Initiative Special Report2022-12-15015 December 2022 Industry Groundwater Protection Initiative Special Report L-MT-22-052, L-MT-22-052 Monticello Nuclear Generating Plant 10 CFR 50.55a Request No. Pr 08, Request for HPCI Pump Quarterly Alternative2022-12-15015 December 2022 L-MT-22-052 Monticello Nuclear Generating Plant 10 CFR 50.55a Request No. Pr 08, Request for HPCI Pump Quarterly Alternative L-MT-22-046, 2022 Annual Report of Changes in Emergency Core Cooling System Evaluation Models Pursuant to 10 CFR 50.462022-12-13013 December 2022 2022 Annual Report of Changes in Emergency Core Cooling System Evaluation Models Pursuant to 10 CFR 50.46 L-MT-22-048, Update to the Monticello Technical Specification Bases2022-11-28028 November 2022 Update to the Monticello Technical Specification Bases 2024-09-26
[Table view] Category:Response to Request for Additional Information (RAI)
MONTHYEARL-MT-24-038, Subsequent License Renewal Application Response to Request for Additional Information - 3rd Round RAI2024-10-15015 October 2024 Subsequent License Renewal Application Response to Request for Additional Information - 3rd Round RAI L-MT-24-029, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information-Supplement to Set 1 Part 2 and Response to 2ci Round RAI2024-09-13013 September 2024 Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information-Supplement to Set 1 Part 2 and Response to 2ci Round RAI L-MT-24-017, Response to Request for Additional Information Regarding License Amendment Request to Revise Monticello Technical Specification Surveillance Requirement 3.8.6.6 (EPID-L-2023-LLA-01602024-06-0404 June 2024 Response to Request for Additional Information Regarding License Amendment Request to Revise Monticello Technical Specification Surveillance Requirement 3.8.6.6 (EPID-L-2023-LLA-0160 L-MT-24-015, Response to Request for Additional Information - Alternative Request VR-09 for OMN-172024-05-16016 May 2024 Response to Request for Additional Information - Alternative Request VR-09 for OMN-17 ML24092A2152024-03-27027 March 2024 Email: Requests for Information to Support Deis ML24088A2152024-02-20020 February 2024 Feb. 20, 2024 Xcel Energy Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information for Monticello Nuclear Generating Plant L-MT-24-007, Response to NRC Request for Additional Information on Proposed Inservice Inspection Alternative RR-002 for the Sixth Ten-Year ISI Interval2024-02-15015 February 2024 Response to NRC Request for Additional Information on Proposed Inservice Inspection Alternative RR-002 for the Sixth Ten-Year ISI Interval L-MT-23-056, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 1 Part 22023-12-18018 December 2023 Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 1 Part 2 L-MT-23-049, Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 12023-11-21021 November 2023 Subsequent License Renewal Application Response to Request for Additional Information and Request for Confirmation of Information - Set 1 L-MT-23-046, Subsequent License Renewal Application Response to Request for Additional Information Round 2 - Set 12023-11-0909 November 2023 Subsequent License Renewal Application Response to Request for Additional Information Round 2 - Set 1 L-MT-23-037, Subsequent License Renewal Application Response to Request for Additional Information Set 32023-09-22022 September 2023 Subsequent License Renewal Application Response to Request for Additional Information Set 3 ML23262B0372023-09-19019 September 2023 Response to NRC Request for Additional Information Regarding the 2023 Monticello and Prairie Island Plant Decommissioning Funding Status Reports L-MT-23-036, Subsequent License Renewal Application Response to Request for Additional Information Set 2 and Supplement 62023-09-0505 September 2023 Subsequent License Renewal Application Response to Request for Additional Information Set 2 and Supplement 6 L-MT-23-034, Subsequent License Renewal Application Response to Request for Additional Information Set 12023-08-15015 August 2023 Subsequent License Renewal Application Response to Request for Additional Information Set 1 L-MT-23-005, Response to the NRC Request for Additional Information Regarding the 50.55a Request Pr 08, HPCI Pump Quarterly Testing (EPID Number L-2022-LLR-0088)2023-01-0606 January 2023 Response to the NRC Request for Additional Information Regarding the 50.55a Request Pr 08, HPCI Pump Quarterly Testing (EPID Number L-2022-LLR-0088) ML22220A2722022-08-0808 August 2022 Response to a Request for Additional Informational Regarding the Monticello Fuel Oil Storage Tank Inspection L-MT-22-007, Response to Request for Additional Information for the Monticello Nuclear Generating Plant Alternative Request VR-08 (EPID: L-MT-22-007)2022-07-22022 July 2022 Response to Request for Additional Information for the Monticello Nuclear Generating Plant Alternative Request VR-08 (EPID: L-MT-22-007) ML22161A9152022-06-10010 June 2022 and Prairie Island Nuclear Generating Plant, Units 1 and 2 - Response to a Request for Additional Information Xcel Energy Amendment Request to Create a Common Emergency Plan and Emergency Operations. L-MT-22-024, Response to a Request for Additional Information for the Monticello Nuclear Generating Plant Related to the Amendment to Adopt Advanced Framatome Methodologies2022-06-0606 June 2022 Response to a Request for Additional Information for the Monticello Nuclear Generating Plant Related to the Amendment to Adopt Advanced Framatome Methodologies L-MT-22-022, Response to a Request for Additional Information: Monticello Alternative VR-10, Excess Flow Check Valve Testing Frequency2022-05-25025 May 2022 Response to a Request for Additional Information: Monticello Alternative VR-10, Excess Flow Check Valve Testing Frequency L-MT-21-017, Response to Request for Additional Information (RAI) Related to License Amendment Request to Implement Technical Specifications Task Force Traveler TSTF-505, Revision 22021-04-20020 April 2021 Response to Request for Additional Information (RAI) Related to License Amendment Request to Implement Technical Specifications Task Force Traveler TSTF-505, Revision 2 L-MT-20-036, Response to Request for Additional Information Related to License Amendment Request to Implement Technical Specification Task Force Traveler TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times2020-12-21021 December 2020 Response to Request for Additional Information Related to License Amendment Request to Implement Technical Specification Task Force Traveler TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times L-MT-20-024, Response to Request for Additional Information (RAI) Monticello 10 CFR 50.55a Request: Request RR-016 Associated with the Fifth Ten-Year Inservice Inspection (ISI) Interval2020-07-20020 July 2020 Response to Request for Additional Information (RAI) Monticello 10 CFR 50.55a Request: Request RR-016 Associated with the Fifth Ten-Year Inservice Inspection (ISI) Interval L-MT-20-015, Response to Request for Additional Information (RAI) Long-Term Replacement Steam Dryer Inspection Plan2020-06-0808 June 2020 Response to Request for Additional Information (RAI) Long-Term Replacement Steam Dryer Inspection Plan ML20045E8942020-02-14014 February 2020 Response to a Request for Additional Information for Proposed 10 CFR 50.55a(z)(2) Alternatives to Utilize ASME Code Case N-786-3, Alternative Requirements for Sleeve Reinforcement of Class 2 and 3 Moderate-Energy Carbon Steel Piping, and AS L-MT-19-030, Supplement to a Response for a Request for Additional Information: Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors.2019-05-15015 May 2019 Supplement to a Response for a Request for Additional Information: Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors. L-MT-19-024, Response to a Request for Additional Information for Removal of a Note Associated with Technical Specification 3.5.12019-04-18018 April 2019 Response to a Request for Additional Information for Removal of a Note Associated with Technical Specification 3.5.1 L-MT-19-018, Response to Request for Additional Information: Application to Adopt 10 CFR 50.69, Risk- Informed Categorization & Treatment of Structures, Systems and Components for Nuclear Power Reactors2019-03-13013 March 2019 Response to Request for Additional Information: Application to Adopt 10 CFR 50.69, Risk- Informed Categorization & Treatment of Structures, Systems and Components for Nuclear Power Reactors L-MT-18-058, Response to Request for Additional Information: Application for Technical Specification Change Regarding Risk-Informed Justification for the Relocation of Specific Surveillance Frequency Requirements to ...2018-10-23023 October 2018 Response to Request for Additional Information: Application for Technical Specification Change Regarding Risk-Informed Justification for the Relocation of Specific Surveillance Frequency Requirements to ... L-MT-18-041, Response to Request for Additional Information Re Request for Permanent Exemption from 10CFR50, App R, III.G.2.a Requirements for Exposed Structural Steel2018-07-20020 July 2018 Response to Request for Additional Information Re Request for Permanent Exemption from 10CFR50, App R, III.G.2.a Requirements for Exposed Structural Steel L-MT-18-032, Response to Request for Additional Information Regarding Application to Revise Technical Specifications to Adopt TSTF-542, Reactor Pressure Vessel Water Inventory Control, and Supplement (EPID: L-2017-LLA-03602018-06-0101 June 2018 Response to Request for Additional Information Regarding Application to Revise Technical Specifications to Adopt TSTF-542, Reactor Pressure Vessel Water Inventory Control, and Supplement (EPID: L-2017-LLA-0360 ML18131A2232018-05-11011 May 2018 Prairie and Monticello - Response to Request for Additional Information Regarding Proposed Alternative to Utilize Code Case N-513-4, Evaluation Criteria for Temporary Acceptance of Flaws in Moderate Energy Class 2 or 3 Piping Section XI, Di L-MT-18-013, Response to Request for Additional Information Regarding Exemption Request for Nonconforming Dye Penetrant Examinations of Dry Shielded Canisters (Dscs) 11 Through 152018-04-0505 April 2018 Response to Request for Additional Information Regarding Exemption Request for Nonconforming Dye Penetrant Examinations of Dry Shielded Canisters (Dscs) 11 Through 15 L-MT-17-071, Response to Request for Additional Information Regarding Risk-Informed Request for Exemption from 10CFR50, Appendix R, III.G.2 Requirements for Multiple Spurious Operations of Drywell Spray Motor-Operated Valves2017-11-20020 November 2017 Response to Request for Additional Information Regarding Risk-Informed Request for Exemption from 10CFR50, Appendix R, III.G.2 Requirements for Multiple Spurious Operations of Drywell Spray Motor-Operated Valves L-MT-17-066, Supplemental Information for the Notification of Full Compliance of Required Action for NRC Order EA-12-049 Mitigation Strategies for Beyond-Design-Basis External Events2017-09-28028 September 2017 Supplemental Information for the Notification of Full Compliance of Required Action for NRC Order EA-12-049 Mitigation Strategies for Beyond-Design-Basis External Events L-MT-17-065, License Amendment Request to Revise the Emergency Action Level Scheme - Supplement and Response to Requests for Additional Information2017-09-25025 September 2017 License Amendment Request to Revise the Emergency Action Level Scheme - Supplement and Response to Requests for Additional Information L-MT-17-063, Response to Request for Additional Information Regarding License Amendment Request to Revise Emergency Plan Staff Augmentation Response Times2017-09-20020 September 2017 Response to Request for Additional Information Regarding License Amendment Request to Revise Emergency Plan Staff Augmentation Response Times L-MT-17-025, High Frequency Supplement to Seismic Hazard Screening Report, Response to NRC Request for Information Pursuant to 10CFR50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-Ichi Accid2017-04-11011 April 2017 High Frequency Supplement to Seismic Hazard Screening Report, Response to NRC Request for Information Pursuant to 10CFR50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force Review of Insights from the Fukushima Dai-Ichi Accident L-MT-17-022, Response to Second Round PRA Related RAIs for the License Amendment Request for a Permanent Extension of the 10 CFR 50 Appendix J Containment Type a Test Interval2017-03-29029 March 2017 Response to Second Round PRA Related RAIs for the License Amendment Request for a Permanent Extension of the 10 CFR 50 Appendix J Containment Type a Test Interval L-MT-17-007, Part 3 Response to Probabilistic Risk Assessment (PRA) Related Requests for Additional Information: License Amendment Request for a Permanent Extension of the 10 CFR 50 Appendix J Containment Type a Test Interval2017-02-0707 February 2017 Part 3 Response to Probabilistic Risk Assessment (PRA) Related Requests for Additional Information: License Amendment Request for a Permanent Extension of the 10 CFR 50 Appendix J Containment Type a Test Interval L-MT-17-002, Part 2 Response to Probabilistic Risk Assessment (PRA) Related Requests for Additional Information: License Amendment Request for a Permanent Extension of the 10 CFR 50Appendix J Containment Type a Test Interval2017-01-31031 January 2017 Part 2 Response to Probabilistic Risk Assessment (PRA) Related Requests for Additional Information: License Amendment Request for a Permanent Extension of the 10 CFR 50Appendix J Containment Type a Test Interval L-MT-16-062, Part 1 Response to Probabilistic Risk Assessment Related Requests for Additional Information: License Amendment Request for a Permanent Extension of the 10 CFR 50 Appendix J Containment Type a Test Interval2016-12-16016 December 2016 Part 1 Response to Probabilistic Risk Assessment Related Requests for Additional Information: License Amendment Request for a Permanent Extension of the 10 CFR 50 Appendix J Containment Type a Test Interval L-MT-16-058, Supplement to License Amendment Request to Revise Battery Charger Surveillance Requirement 3.8.4.22016-11-22022 November 2016 Supplement to License Amendment Request to Revise Battery Charger Surveillance Requirement 3.8.4.2 ML16288A0972016-10-14014 October 2016 and Monticello - Response to Generic Letter 2016-01, Monitoring of Neutron-Absorbing Materials in Spent Fuel Pools L-MT-16-044, Response to Request for Additional Information: License Amendment Request for a Permanent Extension of the 10 CFR 50 Appendix J Containment Type a Test Interval2016-10-10010 October 2016 Response to Request for Additional Information: License Amendment Request for a Permanent Extension of the 10 CFR 50 Appendix J Containment Type a Test Interval L-MT-16-045, Response to Request for Additional Information: License Amendment Request to Revise Battery Charger Surveillance Requirement 3.8.4.22016-10-0303 October 2016 Response to Request for Additional Information: License Amendment Request to Revise Battery Charger Surveillance Requirement 3.8.4.2 L-MT-16-041, License Amendment Request for Areva Extended Flow Window Supplement to Address Power Distribution Uncertainties2016-09-14014 September 2016 License Amendment Request for Areva Extended Flow Window Supplement to Address Power Distribution Uncertainties L-MT-16-038, Seventh Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order No. EA-12-049)2016-08-19019 August 2016 Seventh Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order No. EA-12-049) L-MT-16-039, Response to Nuclear Security and Incident Response Requests for Additional Information Regarding Changes to the Monticello Nuclear Generation Plant Physical Security Plan (Revision 16) Pursuant to 10 CFR 50.54(p)(2)2016-08-15015 August 2016 Response to Nuclear Security and Incident Response Requests for Additional Information Regarding Changes to the Monticello Nuclear Generation Plant Physical Security Plan (Revision 16) Pursuant to 10 CFR 50.54(p)(2) ML16221A2742016-07-31031 July 2016 ANP-3435NP, Revision 2, Areva Responses to RAI-8 and RAI-32 from Srxb and Snpb on MNGP EFW Lar. 2024-09-13
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(l Xcel Energy* 2807 West County Road 75 Monticello, MN 55362 November 9, 2023 L-MT-23-046 10 CFR 54.17 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Monticello Nuclear Generating Plant Docket No. 50-263 Renewed Facility Operating License No. DPR-22 Subsequent License Renewal Application Response to Request for Additional Information Round 2 - Set 1
References:
- 1) Letter from Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy to Document Control Desk, Monticello Nuclear Generating Plant Docket No. 50-263, Renewal License Number DPR-22 Application for Subsequent Renewal Operating License dated January 9, 2023, ML23009A353
- 2) Email from the NRC to Northern States Power Company, A Minnesota corporation (NSPM), d/b/a Xcel Energy, Monticello SLRA - Request for Additional Information - Set 1 dated July 19, 2023, ML23200A350 and ML23200A351
- 3) Letter from Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy to Document Control Desk, Monticello Nuclear Generating Plant - Subsequent License Renewal Application Response to Request for Additional Information Set 1 dated August 15, 2023, ML23227A175
- 4) Email from the NRC to Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy, Monticello SLRA - Request for Additional Information - Set 2 dated August 7, 2023, ML23219A107 and ML23219A108
- 5) Letter from Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy to Document Control Desk, Monticello Nuclear Generating Plant Subsequent License Renewal Application Response to Request for Additional Information Set 2 and Supplement 6 dated September 05, 2023, ML23248A474
- 6) Email from the NRC to Northern States Power Company, a Minnesota corporation (NSPM), d/b/a Xcel Energy, Monticello SLRA - Request for Additional Information - Set 3 dated August 25, 2023, ML23237A483
Doc um e nt Co ntro l Desk L-MT-23-046 Page 2
- 7) Letter from Northern States Power Company, a Minnesota corporation (NSPM}, d/b/a Xcel Energy to Document Control Desk, "Monticello Nuclear Generating Plant - Subsequent License Renewal Application Response to Request for Additional Information Set 3" dated September 22, 2023, ML23265A158 8} Email from the NRC to Northern States Power Company, a Minnesota corporation (NSPM}, d/b/a Xcel Energy, "Monticello SLRA- Request for Additional Information - Round 2 - Set 1" dated October 13, 2023, ML23289A003 Northern States Power Company, a Minnesota corporation, doing business as Xcel Energy hereafter "NSPM", is submitting responses to requests for additional information (RAls) to the Subsequent License Renewal Application, listed in Reference 1.
RAI Sets 1, 2, and 3 were issued by the NRC in References 2, 4, and 6, respectively .
Responses were provided in References 3, 5, and 7, respectively. Additional RAls were issued by the NRC as Round 2 - Set 1 on October 13, 2023 (Reference 8) . The responses to RAI Round 2 - Set 1 are provided in the Enclosures . No SLRA changes have been identified as a result of these responses.
Summary of Commitments This letter makes no new commitments and no revisions to existing commitments .
I declare under penalty of perjury that the foregoing is true and correct.
Executed on November- - '\ ~ 2023 .
Shawn Hafe Site Vice President, Monticello Nuclear Generating Plant Northern States Power Company - Minnesota cc : Administrator, Region Ill, USNRC Project Manager, Monticello, USNRC Resident Inspector, Monticello, USNRC Minnesota Department of Commerce
Document Control Desk L-MT-23-046 Page 3 Enclosures Index Enclosure Subject No.
01 RAI B.2.3.27-3a 02 RAI B.2.3.17-1a 1
RAI B.2.3.27-3a
Monticello Nuclear Generating Plant Docket 50-263 L-MT-23-046 1 Page 1 of 5 RAI B.2.3.27-3a Regulatory Basis 10 CFR 54.21(a)(3) requires an applicant to demonstrate that the effects of aging for structures and components will be adequately managed so that the intended function(s) will be maintained consistent with the current licensing basis for the period of extended operation. One of the findings that the staff must make to issue a renewed license (10 CFR 54.29(a)) is that actions have been identified and have been or will be taken with respect to managing the effects of aging during the period of extended operation on the functionality of structures and components that have been identified to require review under 10 CFR 54.21, such that there is reasonable assurance that the activities authorized by the renewed license will continue to be conducted in accordance with the current licensing basis. In order to complete its review and enable making a finding under 10 CFR 54.29(a), the staff requires additional information in regard to the matters described below.
Background:
As amended by letters dated July 18, 2023 (ML23199A154) and September 22, 2023 (ML23265A158), the SLRA was revised to reflect that uncoated and underground (a) steel piping in the offgas system; and (b) stainless steel piping in the control rod drive (CRD) and radwaste solid and liquid (RAD) systems will be managed for loss of material and cracking (stainless steel only) using the Buried and Underground Piping and Tanks program. In addition, by letter September 22, 2023, a new enhancement and exception were added to the Buried and Underground Piping and Tanks program related to the use of external coatings for underground piping, which stated the following (in part):
- [n]ew and replacement coatings for underground components are to be consistent with Table 1 of [NACE] SP0169-2007 [Control of External Corrosion on Underground or Submerged Metallic Piping Systems] or Section 3.4 of NACE RP0285-2002 [Corrosion Control of Underground Storage Tank Systems by Cathodic Protection]. Existing coatings for underground components at MNGP were installed per site design specifications. Site design specifications did not require coatings on underground components[t]his exception is acceptable because operating experience [OE] demonstrates that the lack of moisture intrusion does not lead to accelerated degradation of the uncoated underground components at MNGP.
The response to RAI B.2.3.27-3 (ML23265A158) states the following (in part):
- [t]he visual examinations of the removed [carbon steel] piping sections showed that both of the CRD pipes experienced severe corrosion of the external surfaces in the regions exposed to the ground water present between the buildings.
- [b]oth CRD pipeswere replaced with uncoated stainless steel piping.
- [a] removable 1/4 stainless steel plate anchored to the wall with stainless steel concrete anchors on the Reactor Building inside wall provides access into the penetration. The Reactor Building wall opening is packed with removable Kaowool [insulation]. The piping is grouted for about 1 foot into the Turbine Building wall. The piping in the Turbine Building is also packed with removable Kaowool.
Monticello Nuclear Generating Plant Docket 50-263 L-MT-23-046 1 Page 2 of 5
- [a]ctions have been taken to identify other in scope underground piping that may have been inadvertently omitted from the SLRA.There are 35 penetrations identified where pipe went between the Reactor Building and Turbine Building. All other piping that run through the 1 seismic gap between the Reactor Building and Turbine Building are managed by the External Surfaces Monitoring of Mechanical Components AMP based on the environment and observed condition of the external surfaces of the samples pipingThe expectations of this [program] element [detection of aging effects of the External Surfaces Monitoring of Mechanical Components AMP] are being met with the maintenance notifications to perform periodic inspections described above as part of the evaluation of this issue. [emphasis added]
SLRA Section B.2.3.27, Buried and Underground Piping and Tanks, includes a discussion in the plant-specific OE section about an increasing trend of chloride concentrations in groundwater samples between 2011 and 2015. The SLRA states that the increase in chloride concentration was likely due to salt treatment during the winter months. In addition, as noted in RAI B.2.3.171 (ML23237A483), corrective action document (AR 01223696) states that insulation and grout are possible sources of the chlorides that caused the stress corrosion cracking of the stainless steel standby liquid control tank.
GALL-SLR Report AMP XI.M41, Buried and Underground Piping and Tanks, recommends the following:
- One inspection for underground steel and stainless steel piping in each 10year inspection interval (this number can increase to two inspections for underground steel based on the piping length).
- External coatings for (a) underground steel piping; and (b) stainless steel piping in chloride containing environments.
In addition, GALL-SLR Report AMP XI.M41 states [a]dditional inspections, beyond those in Table XI.M41-2 [Inspection of Buried and Underground Piping and Tanks] may be appropriate if exceptions are taken to program element 2, preventive actions, or in response to plant-specific OE. Also, GALL-SLR Report,Section IX.D, Environments, states that the term underground includes exposure to multiple environments including groundwater and condensation.
Issue:
The justification for the new exception (relating to the lack of external coatings on existing underground piping) does not address the plant-specific OE. Underground piping at the site is exposed to moisture intrusion (i.e., groundwater and condensation) and accelerated corrosion of inscope underground piping has occurred. As noted above, additional inspections, beyond those in GALL-SLR Report Table XI.M41-2, may be appropriate if exceptions are taken to the recommended preventive actions or in response to plant-specific OE. The staff notes that the installation of insulation inside the penetration may tend to aggravate corrosion, if it is exposed to moisture.
Based on (a) plantspecific OE involving severe corrosion of inscope underground piping; (b) absence of external coatings for existing inscope underground steel and stainless steel piping; and (c) potential exposure of the subject piping to elevated levels of chlorides (from either groundwater, grout, or insulation), it is unclear why inspections consistent with GALL-SLR
Monticello Nuclear Generating Plant Docket 50-263 L-MT-23-046 1 Page 3 of 5 Report Table XI.M41-2 (i.e., one inspection in each 10year interval) is appropriate for inscope underground steel and stainless steel piping.
Based on the extent of condition discussions in the RAI response, the portions of piping systems that run between the reactor building and turbine building were not inspected as part of the existing External Surfaces Monitoring of Mechanical Components AMP. The response indicates that the expectations of the associated detection of aging effects program element of the AMP are being met with the maintenance notifications to perform periodic inspections described above. It is unclear what maintenance notifications to perform periodic inspections means, and whether the current External Surfaces Monitoring of Mechanical Components AMP includes the inspection activities currently being credited for managing the effects of aging for the pertinent portions of the applicable piping systems. Because the program previously did not include these inspections, it is unclear whether an enhancement to the External Surfaces Monitoring of Mechanical Components AMP is warranted to ensure these credited activities will be performed during the period of extended operation. In addition, because the response cites a portion of the guidance related to inspecting components that are not readily visible whenever they are made accessible, it is not clear what frequency the inspections will be performed.
Request:
- 1. Based on the issues outlined above (i.e., adverse plantspecific OE, absence of external coatings, potential exposure of piping to elevated levels of chlorides), state the basis for why one inspection in each 10year interval is appropriate for inscope underground steel and stainless steel piping.
- 2. Provide information whether an enhancement to the External Surfaces Monitoring of Mechanical Components AMP is warranted. Include information related to the frequency of these proposed inspections or the basis for establishing the inspection frequency.
Response to RAI B.2.3.27-3a:
- 1. The basis for one inspection in each 10-year interval is discussed separately for Off-Gas (Underground Steel) and CRD (Underground Stainless Steel):
Off-Gas (Underground Steel): The Off-Gas Systems in-scope underground steel piping has no record of degradation. There is no MNGP operating experience that identifies moisture intrusion into this one vault with an underground environment. The Table in Section B.2.3.27 on page B-198 of the SLRA as revised in L-MT-23-031 (Reference 2) Enclosure 06b states that the smaller of 2% of the piping length or 2 inspections are required for underground steel piping and Note 1 states underground piping found in the Off-Gas System is included.
The plant-specific OE for the degradation of the steel CRD piping in the seismic gap between the turbine building and reactor building is not applicable because the environment from that OE allowed for periodic wetting of the steel piping by groundwater, which is not the case for the underground piping in the Off-Gas System as stated above. Deficiencies will be documented in accordance with the sites 10 CFR Part 50, Appendix B, Section XVI, Corrective Action Program (CAP) and used to inform changes to the AMP, as necessary.
CRD (Underground Stainless Steel) Piping: MNGP selected the Buried and Underground Piping AMP to manage aging of the CRD piping routed between the turbine building and reactor building in the seismic gap. The configuration of the environment of the CRD piping between the turbine and reactor buildings is unique and is not directly addressed in the
Monticello Nuclear Generating Plant Docket 50-263 L-MT-23-046 1 Page 4 of 5 GALL-SLR. The location is susceptible to ground water intrusion and can result in periodic wetting of the piping. Corroded carbon steel piping was replaced with stainless steel piping in the two lowest penetrations between the turbine building and the reactor building. This lowest, below grade reactor to turbine building penetration (for the CRD Piping) was modified to provide access for inspection of the new stainless steel piping. A removable plate allows access for future inspections.
- i. The CRD piping is in an underground environment and will be managed by the Buried and Underground Piping and Tanks AMP. The SLRA changes due to recent operating experience are documented in L-MT-23-031 Enclosure 06b (Reference 2) and L-MT 037 Enclosure 01 (Reference 4).
ii. MNGP does have buried, coated stainless steel piping. An inspection of opportunity found stainless steel piping with damaged coating which exposed the piping to groundwater. There was no indication of external corrosion in the stainless steel piping.
iii. Inspection of insulated stainless steel piping at MNGP subject to condensation environment has found no loss of material such as due to pitting and crevice corrosion.
iv. MNGP will inspect the underground stainless steel piping prior to the SPEO and once every 10 years thereafter per Commitment 30 in Table A-3 and Section B.2.3.27 of the SLRA as amended by L-MT-23-025 Enclosure 06a (Reference 1), L-MT-23-031 Enclosure 06b (Reference 2), L-MT-23-036 Enclosure 02 (Reference 3), and L-MT 037 Enclosure 01 (Reference 4).
- v. Consistent with the recommendation of GALL SLR, the Buried and Underground Piping and Tanks AMP will confirm that loss of material is not occurring in stainless steel components exposed to an underground environment. Deficiencies will be documented in accordance with the sites 10 CFR Part 50, Appendix B, Section XVI, CAP and used to inform changes to the AMP, as necessary.
vi. The chemical composition of refractory ceramic fiber products such as Kaowool and Cerablanket is 45% alumina, 50 to 55% silica with lesser amounts of ferric oxide, titanium oxide, sodium and potassium oxides and traces of other impurities.
Manufacturers data sheet states Kaowool contains 1 to 2 ppm leachable chlorides. The SDS sheet states this blanket material is not soluble in water. As noted in the plant-specific OE described above for the buried stainless steel piping with damaged coating and absence of corrosion, the groundwater chlorides do not currently require a change in the inspections for the MNGP AMP from what is provided in the GALL-SLR guidance for stainless steel piping.
Consistent with the recommendation of GALL-SLR, the Buried and Underground Piping and Tanks AMP will confirm that loss of material and cracking is not occurring in carbon and stainless steel components exposed to an underground environment. Deficiencies will be documented in accordance with the sites 10 CFR Part 50, Appendix B, Section XVI, CAP.
- 2. Enhancement for External Surfaces Monitoring of Mechanical Components AMP:
An enhancement to the External Surface Monitoring of Mechanical Components AMP is not warranted for the piping in between the reactor building and turbine building.
The conditions of the piping between the reactor building and the turbine building over the 52+ years of operation do not indicate that other enhancements to the External Surfaces Monitoring of Mechanical Components AMP are needed for SLR and that aging effects
Monticello Nuclear Generating Plant Docket 50-263 L-MT-23-046 1 Page 5 of 5 associated with those carbon steel and stainless steel pipes can be managed using the program described in the SLRA. The details of the results of the extent of condition were previously captured in L-MT-23-037 Enclosure 01 (Reference 4). GALL-SLR, Chapter XI.M36 states Surfaces that are not readily visible during plant operations and refueling outages are inspected when they are made accessible and at such intervals that would ensure the components intended functions are maintained.
Inspections are guided by and consistent with the CAP element in GALL-SLR Chapter XI.M37 Element 7. Deficiencies will be documented in accordance with the sites 10 CFR Part 50, Appendix B, Section XVI, CAP.
References:
- 1. L-MT-23-025, Monticello Nuclear Generating Plant, Docket No. 50-263, Renewed Facility Operating License No. DPR-22, Subsequent License Renewal Application Supplement 2, ML23177A218.
- 2. L-MT-23-031, Monticello Nuclear Generating Plant, Docket No. 50-263, Renewed Facility Operating License No. DPR-22, Subsequent License Renewal Application Supplement 4 and Responses to Request for Confirmation of Information - Set 1, ML23199A154.
- 3. L-MT-23-036, Monticello Nuclear Generating Plant, Docket No. 50-263, Renewed Facility Operating License No. DPR-22, Subsequent License Renewal Application Response to Request for Additional Information Set 2 and Supplement 6, ML23248A474.
- 4. L-MT-23-037, Monticello Nuclear Generating Plant, Docket No. 50-263, Renewed Facility Operating License No. DPR-22, Subsequent License Renewal Application Response to Request for Additional Information Set 3, ML23265A158.
Associated SLRA Revisions:
No SLRA changes have been identified as a result of this response.
2 RAI B.2.3.17-1a
Monticello Nuclear Generating Plant Docket 50-263 L-MT-23-046 2 Page 1 of 2 RAI B.2.3.17-1a Regulatory Basis:
Title 10 of the Code of Federal Regulations (10 CFR) 54.21(a)(3) requires an applicant to demonstrate that the effects of aging for structures and components will be adequately managed so that the intended function(s) will be maintained consistent with the current licensing basis for the period of extended operation. One of the findings that the U.S. Nuclear Regulatory Commission (NRC) staff must make to issue a renewed license (10 CFR 54.29(a)) is that actions have been identified and have been or will be taken with respect to managing the effects of aging during the period of extended operation on the functionality of structures and components that have been identified to require review under 10 CFR 54.21. In order to complete its review and enable formulation of a finding under 10 CFR 54.29(a), the staff requests additional information regarding the matters described below.
Background:
The response to request for additional information (RAI) B.2.3.17-1 (refer to letter dated September 22, 2023 (ML23265A158)) revised portions of the subsequent license renewal application (SLRA) to reflect that the Monticello ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD (ASME Section XI ISI) program will be used to manage cracking and loss of material for the external portions of the stainless steel standby liquid control tank exposed to uncontrolled indoor air and concrete. The response added new aging management review items (3.2.1-129, 3.3.1-004, 3.3.1-222, and 3.3.1-230) to SLRA Table 3.3.2-17, Standby Liquid Control - Summary of Aging Management Evaluation, with generic note Es indicating a proposal to use a different program than that recommended in NRCs aging management guidance.
The response states:
The ASME Section XI Standby Liquid Control Suction Piping System Leakage Test is performed every two years. The inspection will be part of the ISI AMP for MNGP [Monticello Nuclear Generating Plant], and will provide reasonable assurance that any aging effects for the SLC
[standby liquid control] tank are managed before there is a potential loss of its pressure boundary intended function.
Issue:
The NRC staff notes that prior to the RAI response discussed above, the SLRA had not previously credited the ASME Section XI ISI program for managing the effects of aging for components in the standby liquid control system. In addition, it is unclear what type(s) of ASME Section XI ISI inspection will be performed on the standby liquid control tank, and whether these inspections will also be performed every 2 years. Consequently, unless the ASME Section XI ISI program currently includes the specified activities that are now being credited for managing the effects of aging (loss of material and cracking) for the tank, an enhancement to the ASME Section XI ISI program appears to be warranted.
Monticello Nuclear Generating Plant Docket 50-263 L-MT-23-046 2 Page 2 of 2 Request:
Provide information showing that the activities being credited for managing the effects of aging, as specified in response to RAI B.2.3.17-1, are currently included in the ASME Section XI ISI aging management program or provide information about any enhancement needed to the program to ensure that the associated effects of aging will be adequately managed.
Response to RAI B.2.3.17-1a:
MNGP personnel perform VT-2 examinations on SLC System pressure retaining components in accordance with the ASME Section XI ISI AMP. These exams will detect aging effects that could result in a through wall leak.
The frequency and scope of examinations are sufficient to ensure that the aging effects are detected before the loss of a components intended function(s) and will be adequately age managed during the SPEO. The inspections and their frequency are consistent with ASME code requirements.
The ISI Program Owner ensures compliance with the ISI-PLAN-6-BASIS (6th Interval ISI Plan -
Basis Document) and the ISI-PLAN-6-D (6th Interval ISI Plan - Appendix D, Inspection Plan and Schedule Tables) documents. This ensures performance of the System Leakage Test for the SLC System at least once in each of the 3 periods of the ISI interval. Thus, it will be performed three times in a ten-year period per the ISI Program. This represents a different frequency for the inspection than what was previously stated in the Response to RAI B.2.3.17-1 in Reference 1. However, the frequency of the inspection and its ability to manage aging in the SLC System is in accordance with the ISI AMP.
The Program is implemented by MNGPs ISI Plan and SCPTP (System and Component Pressure Testing Program).
No enhancements to the ISI program are required.
References:
- 1. L-MT-23-037, Monticello Nuclear Generating Plant, Docket No. 50-263, Renewed Facility Operating License No. DPR-22, Subsequent License Renewal Application Response to Request for Additional Information Set 3, ML23265A158.
Associated SLRA Revisions:
No SLRA changes have been identified as a result of this response.