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EPID:L-2018-LLA-0008, Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components (Sscs) for Nuclear Power Reactors (Approved, Closed) |
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MONTHYEARBSEP 17-0098, Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components (Sscs) for Nuclear Power Reactors2018-01-10010 January 2018 Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components (Sscs) for Nuclear Power Reactors Project stage: Request ML18045A8492018-02-14014 February 2018 NRR E-mail Capture - Brunswick 50.69 - Risk Informed SSC Acceptance Review Project stage: Acceptance Review ML18130A0212018-05-0909 May 2018 NRR E-mail Capture - Brunswick - Adoption of 10 CFR 50.69 - Hwpra and Xfpra Audit Plan and Setup of Online Reference Portal Project stage: Other ML18180A4182018-07-0202 July 2018 Audit Plan for Request to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components Forr Nuclear Power Reactors (EPID L-2018-LLA-0008; L-2018-LLA-0034) Project stage: Other ML18220A7902018-08-0707 August 2018 NRR E-mail Capture - Brunswick - Adoption of 10 CFR 50.69 - Supplement to the Hwpra and Xfpra Audit Plan for BSEP Onsite Audit Project stage: Other ML18263A3042018-09-20020 September 2018 NRR E-mail Capture - Brunswick Draft RAIs - LAR to Allow Implementation of the Provisions 10 CFR 50.69 Project stage: Draft RAI RA-18-0144, Response to March 12, 2012, Request for Information Enclosure 2, Recommendation 2.1, Flooding, Required Response 3, Flooding Focused Evaluation Summary Report2018-09-27027 September 2018 Response to March 12, 2012, Request for Information Enclosure 2, Recommendation 2.1, Flooding, Required Response 3, Flooding Focused Evaluation Summary Report Project stage: Request ML18282A1492018-10-0909 October 2018 NRR E-mail Capture - Brunswick RAIs - LAR to Allow Implementation of the Provisions 10 CFR 50.69 Project stage: RAI RA-18-0178, Response to NRC Request for Additional Information (RAI) Regarding Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components (Sscs) for ...2018-11-0202 November 2018 Response to NRC Request for Additional Information (RAI) Regarding Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components (Sscs) for ... Project stage: Response to RAI ML18282A2242018-11-14014 November 2018 Regulatory Audit Summary Regarding License Amendment Requests to Adopt 10 CFR 50.69 Project stage: Other ML18360A0352018-12-21021 December 2018 NRR E-mail Capture - Brunswick Draft 2nd Round RAIs - LAR to Allow Implementation of the Provisions 10 CFR 50.69 Project stage: Draft RAI ML19015A0302019-01-14014 January 2019 NRR E-mail Capture - Brunswick 2nd Round RAIs - LAR to Allow Implementation of the Provisions 10 CFR 50.69 Project stage: RAI RA-19-0010, Response to NRC RAI Re Application to Adapt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors2019-02-13013 February 2019 Response to NRC RAI Re Application to Adapt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors Project stage: Request ML19056A2212019-02-25025 February 2019 NRR E-mail Capture - Brunswick Draft 3rd Round RAI - LAR to Allow Implementation of the Provisions 10 CFR 50.69 Project stage: Draft RAI ML19067A2712019-03-0707 March 2019 NRR E-mail Capture - Brunswick 3rd Round RAI - LAR to Allow Implementation of the Provisions 10 CFR 50.69 Project stage: RAI RA-19-0152, Response to NRC Request for Additional Information (RAI) Regarding Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures,Systems, and Components (Sscs) for Nuclear Power Reactors.2019-04-0808 April 2019 Response to NRC Request for Additional Information (RAI) Regarding Application to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures,Systems, and Components (Sscs) for Nuclear Power Reactors. Project stage: Response to RAI ML19149A2102019-07-0101 July 2019 Regulatory Audit Summary, License Amendment Request to Adopt 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Plants Project stage: Other ML19149A4712019-09-17017 September 2019 Issuance of Amendment Nos. 292 and 320, Adopt 10 CFR 50.69 Risk-Informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors Project stage: Approval 2018-08-07
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Category:E-Mail
MONTHYEARML24179A1292024-06-24024 June 2024 Acceptance Review for LAR to Revise TS to Adopt TSTF-234-A, Revision 1 ML23248A2612023-09-0505 September 2023 NRR E-mail Capture - Brunswick Steam Electric Plant, Units 1 and 2 - Acceptance of License Amendment Request to Revise the 10 CFR 50.69 Categorization Process ML23202A0652023-07-19019 July 2023 NRR E-mail Capture - Request for Additional Information - Brunswick Steam Electric Plant, Units 1 and 2, Torus Liner Inspection Alternative Request (L-2022-LLR-0089) ML23142A2732023-05-22022 May 2023 Duke Fleet - Request for Additional Information Proposed Alternative for Steam Generator Welds in Accordance with 10 CFR 50.55a(z)(1) ML23073A2282023-03-13013 March 2023 Duke Fleet- Adoption of TSTF-554, Revision 1, Revise Reactor Coolant Leakage Requirements - Acceptance Review ML23032A2472023-01-26026 January 2023 Document Request Letter for Brunswick Upcoming RP Inspection 2023002 ML23018A1892023-01-17017 January 2023 Document Request for RP Inspection at Brunswick Inspection Report 2023-01 ML23006A0642023-01-0606 January 2023 NRR E-mail Capture - Acceptance Review Results for Brunswick, Unit Nos. 1 and 2 - Proposed Alternative Request RA-22-0308 ML23006A1892023-01-0606 January 2023 NRR E-mail Capture - Corrected - Acceptance Review Results for Brunswick, Unit Nos. 1 and 2 - Proposed Alternative Request RA-22-0308 NRC-2100-2022, EN 55999 Valcor Coil Shell Assemblies Final Notification (004)2022-09-12012 September 2022 EN 55999 Valcor Coil Shell Assemblies Final Notification (004) NRC 2110-2022, EN 55999 - Valcor Engineering Corporation (009)2022-07-18018 July 2022 EN 55999 - Valcor Engineering Corporation (009) ML22115A1412022-04-25025 April 2022 NRR E-mail Capture - Duke Common EOF Relocation - Request for Addition Information ML22038A1572022-02-0707 February 2022 NRR E-mail Capture - Duke Energy Fleet - Acceptance of License Amendment Request Regarding Adoption of TSTF-541, Revision 2 ML22018A0272022-01-18018 January 2022 2022 All RFI Responses - Exercise and Program Inspections - Revl ML21357A0472021-12-23023 December 2021 NRR E-mail Capture - Brunswick Steam Electric Plant, Units 1 and 2 - Acceptance of License Amendment Request Regarding Adoption of TSTF-580 ML21361A0122021-12-23023 December 2021 NRR E-mail Capture - Accepted for Review - Duke Energy Fleet License Amendment Request to Relocate Emergency Operations Facility ML21354A8612021-12-15015 December 2021 NRR E-mail Capture - Request for Additional Information - Duke Fleet Request RA-19-0352 - Alternative for RPV Closure Stud Exams (L-2020-LLR-0156) ML21277A0952021-10-0101 October 2021 NRR E-mail Capture - Request for Additional Information - Brunswick Exemption Request from 10CFR 55.47 License Operator Exam Two-year Waiver Limit ML21200A1582021-07-16016 July 2021 NRR E-mail Capture - Accepted for Review - Brunswick License Amendment Request to Adopt TSTF-439, Eliminate Second Completion Times Limiting Time from Discovery ML21168A0042021-06-17017 June 2021 Notification of Inspection and Request for Information ML21137A1622021-04-26026 April 2021 NRR E-mail Capture - Accepted for Review - Brunswick License Amendment Request to Adopt TSTF-505 Risk-Informed Completion Time (L-2021-LLA-0060) ML21082A0162021-03-22022 March 2021 Accepted for Review - Brunswick License Amendment Request to Change Tech Spec Limit for Standby Liquid Control System Boron Solution Storage Tank Volume L-2021-LLA-0022 ML21075A0032021-03-12012 March 2021 Emergency Preparedness Exercise Inspection Request for Information for - Brunswick, Catawba, North Anna, Oconee, Vogtle 1 & 2 ML21049A2632021-02-0404 February 2021 NRR E-mail Capture - Request for Additional Information - Duke Energy Fleet License Amendment Request to Revise Emergency Plan ML21019A3772021-01-13013 January 2021 002 Radiation Safety Baseline Inspection Information Request ML21007A3722021-01-0707 January 2021 NRR E-mail Capture - Acceptance Review - Duke Fleet - RA-19-0352 - Proposed Alternative for Reactor Vessel Close Stud Examinations (L-2020-LLR-0156) ML20323A4072020-11-18018 November 2020 NRR E-mail Capture - Request for Additional Information - Brunswick License Exemption Request from 10CFR73 Annual Force on Force Exercise Requirements (EPIC L-2020-LLE-0180) ML20309A5212020-10-29029 October 2020 Request for Additional Information - Brunswick License Amendment Request to Modify Its Approved 10 CFR 50.69, Risk-Informed Categorization and Treatment of SSC Categorization Process ML20294A0642020-10-20020 October 2020 NRR E-mail Capture - Accepted for Review - Duke Energy Fleet License Amendment Request to Adopt TSTF-582 RPV Water Inventory Control Enhancements(L-2020-LLA-0218) ML20297A3102020-10-13013 October 2020 NRR E-mail Capture - Acceptance Review - Duke Fleet - RA-20-0191 - Request to Use a Provision of a Later Edition of the ASME B&PV Code, Section XI - IWA-5120, IWA-5213, IWA-5241, IWA-5242, and IWA-5250 (L-2020-LLR-0126) ML20297A3082020-10-0707 October 2020 NRR E-mail Capture - Acceptance Review - Duke Fleet - RA-20-0263 - Request to Use a Provision of a Later Edition of the ASME B&PV Code, Section XI for Repair/Replacement (L-2020-LLR-0124) ML20297A3092020-10-0606 October 2020 NRR E-mail Capture - Acceptance Review - Duke Fleet - RA-20-0262 - Request to Use a Provision of a Later Edition of the ASME B&PV Code, Section XI - IWA-4540(b) (L-2020-LLR-0125) ML20275A2972020-10-0101 October 2020 NRR E-mail Capture - Request for Additional Information - Brunswick Request for Alternate Examination of Reactor Vessel Nozzles ML21033A8562020-08-0505 August 2020 NRR E-mail Capture - Accepted for Review - Brunswick Relief Request for RPV Nozzle-to-Vessel Weld and Inner Radii Examination Requirements EPID-L-2020-LLR-0091 ML20121A1262020-04-29029 April 2020 Radiation Safety Baseline Inspection Information Request ML20111A1212020-04-20020 April 2020 NRR E-mail Capture - Accepted for Review - Brunswick Request for Alternative to Examination Category B-N-1 (VT-3) Visual Examination of Accessible Areas of the Reactor Vessel Interior - EPID: L-2020-LLR-0048 ML20017A1602020-01-17017 January 2020 E-mail Notification of Inspection and Request for Additional Information ML19283D0852019-10-0909 October 2019 Request for Additional Information - Brunswick Atrium 11 LAR ML19252A4572019-09-0808 September 2019 (FEMA Email 09-08-19) Tentative Notification of Brunswick Preliminary Capability Assessment Results ML19252A4092019-09-0606 September 2019 (E-mail to FEMA 09-06-19) FEMA Notification for Planned Restart of Brunswick Units 1 and 2 ML19219A2132019-08-0707 August 2019 NRR E-mail Capture - Duke Energy Fleet - Acceptance of Requested Licensing Action Amendment Requests to Relocate the TSs Staff Qualification Requirements to the Duke Energy Corporation QAPD ML19179A1312019-06-27027 June 2019 NRR E-mail Capture - Brunswick RAIs - LAR to Revise TS 5.5.12, Primary Containment Leakage Rate Testing Program for Permanent Extension of Maximum Appendix J Test Intervals (L 2019-LLA-0031) ML19177A0122019-06-25025 June 2019 NRR E-mail Capture - Draft Brunswick RAIs - LAR to Revise TS 5.5.12, Primary Containment Leakage Rate Testing Program for Permanent Extension of Maximum Appendix J Test Intervals (L 2019-LLA-0031) ML19162A3902019-06-11011 June 2019 NRR E-mail Capture - Brunswick Steam Electric Plant, Units 1 and 2 - Acceptance of Requested Licensing Action Fourth 10-Year Inservice Inspection Interval ISI-12 ML19162A3912019-06-11011 June 2019 NRR E-mail Capture - Duke Energy Fleet - Acceptance of Requested Licensing Action Relief Request (19-GO-001) Proposed Alternative to Use Encoded Phased Array Ultrasonic Examination in Lieu of Radiography ML19092A1152019-04-0101 April 2019 NRR E-mail Capture - Brunswick Steam Electric Plant, Unit Nos. 1 and 2 - Acceptance of Requested Licensing Action Amendment Request to Modify Surveillance Requirements for Safety Relief Valves (L-2019-LLA-0043) ML19092A1142019-04-0101 April 2019 NRR E-mail Capture - Brunswick Plant, Unit 1 and 2 - Acceptance of Requested Licensing Action Amendment Request to Modify TS 5.5.12 for Permanent Extension of Type a and Type C Leak Rate Test Frequencies (L-2019-LLA-0031) ML19067A2712019-03-0707 March 2019 NRR E-mail Capture - Brunswick 3rd Round RAI - LAR to Allow Implementation of the Provisions 10 CFR 50.69 ML19065A0962019-03-0606 March 2019 NRR E-mail Capture - Brunswick RAIs - LAR to Revise Allowable Value for TS 3.3.8.1 Time Delay on Loss of Voltage ML19058A0742019-02-26026 February 2019 NRR E-mail Capture - Draft Brunswick RAIs - LAR to Revise Allowable Value for TS 3.3.8.1 Time Delay on Loss of Voltage 2024-06-24
[Table view] Category:Request for Additional Information (RAI)
MONTHYEARML23202A0652023-07-19019 July 2023 NRR E-mail Capture - Request for Additional Information - Brunswick Steam Electric Plant, Units 1 and 2, Torus Liner Inspection Alternative Request (L-2022-LLR-0089) ML23142A2732023-05-22022 May 2023 Duke Fleet - Request for Additional Information Proposed Alternative for Steam Generator Welds in Accordance with 10 CFR 50.55a(z)(1) ML23032A2472023-01-26026 January 2023 Document Request Letter for Brunswick Upcoming RP Inspection 2023002 ML23018A1892023-01-17017 January 2023 Document Request for RP Inspection at Brunswick Inspection Report 2023-01 ML22192A0862022-07-12012 July 2022 RQ Inspection Notification Letter ML22115A1412022-04-25025 April 2022 NRR E-mail Capture - Duke Common EOF Relocation - Request for Addition Information ML21354A8612021-12-15015 December 2021 NRR E-mail Capture - Request for Additional Information - Duke Fleet Request RA-19-0352 - Alternative for RPV Closure Stud Exams (L-2020-LLR-0156) ML21277A0952021-10-0101 October 2021 NRR E-mail Capture - Request for Additional Information - Brunswick Exemption Request from 10CFR 55.47 License Operator Exam Two-year Waiver Limit ML21239A0652021-09-0808 September 2021 Request for Additional Information Regarding Proposed Alternative to ASME Section XI Requirements for Repair - Replacement of Buried Service Water Piping (EPID L-021-LLR-0014) - Public ML21075A0032021-03-12012 March 2021 Emergency Preparedness Exercise Inspection Request for Information for - Brunswick, Catawba, North Anna, Oconee, Vogtle 1 & 2 ML21049A2632021-02-0404 February 2021 NRR E-mail Capture - Request for Additional Information - Duke Energy Fleet License Amendment Request to Revise Emergency Plan ML21019A3772021-01-13013 January 2021 002 Radiation Safety Baseline Inspection Information Request ML20323A4072020-11-18018 November 2020 NRR E-mail Capture - Request for Additional Information - Brunswick License Exemption Request from 10CFR73 Annual Force on Force Exercise Requirements (EPIC L-2020-LLE-0180) ML20309A5212020-10-29029 October 2020 Request for Additional Information - Brunswick License Amendment Request to Modify Its Approved 10 CFR 50.69, Risk-Informed Categorization and Treatment of SSC Categorization Process ML20275A2972020-10-0101 October 2020 NRR E-mail Capture - Request for Additional Information - Brunswick Request for Alternate Examination of Reactor Vessel Nozzles ML20017A1602020-01-17017 January 2020 E-mail Notification of Inspection and Request for Additional Information ML19283C5532019-10-18018 October 2019 Redacted - Brunswick Steam Electric Plant, Units 1 and 2 - Request for Additional Information ML19283D0852019-10-0909 October 2019 Request for Additional Information - Brunswick Atrium 11 LAR ML19179A1312019-06-27027 June 2019 NRR E-mail Capture - Brunswick RAIs - LAR to Revise TS 5.5.12, Primary Containment Leakage Rate Testing Program for Permanent Extension of Maximum Appendix J Test Intervals (L 2019-LLA-0031) ML19177A0122019-06-25025 June 2019 NRR E-mail Capture - Draft Brunswick RAIs - LAR to Revise TS 5.5.12, Primary Containment Leakage Rate Testing Program for Permanent Extension of Maximum Appendix J Test Intervals (L 2019-LLA-0031) ML19081A0722019-03-21021 March 2019 Notification of Inspection and Request for Information for NRC Problem Identification and Resolution Inspection ML19067A2712019-03-0707 March 2019 NRR E-mail Capture - Brunswick 3rd Round RAI - LAR to Allow Implementation of the Provisions 10 CFR 50.69 ML19065A0962019-03-0606 March 2019 NRR E-mail Capture - Brunswick RAIs - LAR to Revise Allowable Value for TS 3.3.8.1 Time Delay on Loss of Voltage ML19058A0742019-02-26026 February 2019 NRR E-mail Capture - Draft Brunswick RAIs - LAR to Revise Allowable Value for TS 3.3.8.1 Time Delay on Loss of Voltage ML19056A2212019-02-25025 February 2019 NRR E-mail Capture - Brunswick Draft 3rd Round RAI - LAR to Allow Implementation of the Provisions 10 CFR 50.69 ML19015A0302019-01-14014 January 2019 NRR E-mail Capture - Brunswick 2nd Round RAIs - LAR to Allow Implementation of the Provisions 10 CFR 50.69 ML19010A3872019-01-10010 January 2019 NRR E-mail Capture - Brunswick RAIs - LAR to Revise TSs to Adopt TSTF-439, Eliminate Second Completion Times Limiting Time from Discovery of Failure to Meet an LCO ML18360A0352018-12-21021 December 2018 NRR E-mail Capture - Brunswick Draft 2nd Round RAIs - LAR to Allow Implementation of the Provisions 10 CFR 50.69 ML18360A0362018-12-21021 December 2018 NRR E-mail Capture - Draft Brunswick RAIs - LAR to Revise TSs to Adopt TSTF-439, Eliminate Second Completion Times Limiting Time from Discovery of Failure to Meet an LCO ML18282A1492018-10-0909 October 2018 NRR E-mail Capture - Brunswick RAIs - LAR to Allow Implementation of the Provisions 10 CFR 50.69 ML18263A3042018-09-20020 September 2018 NRR E-mail Capture - Brunswick Draft RAIs - LAR to Allow Implementation of the Provisions 10 CFR 50.69 ML18250A3082018-08-31031 August 2018 NRR E-mail Capture - Brunswick RAIs - LAR to Revise TS to Relocate the Pressure-Temperature Limits to the Pressure and Temperature Limits Report ML18225A0122018-08-10010 August 2018 NRR E-mail Capture - Draft Brunswick RAIs - LAR to Revise TS to Relocate the Pressure-Temperature Limits to the Pressure and Temperature Limits Report RA-18-0011, Response to Request for Supplemental Information Regarding Duke Energy'S Response to GL 2016-01 Monitoring of Neutron-Absorbing Materials in Spent Fuel Pools2018-05-30030 May 2018 Response to Request for Supplemental Information Regarding Duke Energy'S Response to GL 2016-01 Monitoring of Neutron-Absorbing Materials in Spent Fuel Pools ML18130A8262018-05-15015 May 2018 Supplemental Information Needed for Acceptance. Amendment Request to Revise the Technical Specifications to Relocate the Pressure Temperature Limit Curves to a Pressure and Temperature Limits Report ML18088A0072018-03-27027 March 2018 NRR E-mail Capture - Brunswick Units 1 & 2 Request for Additional Information - Relief Request for RPV Shell Circumferential Weld Examination (L-2018-LLR-0001) ML18071A3732018-03-12012 March 2018 NRR E-mail Capture - Correction: Brunswick Unit 1 and Unit 2 Request for Additional Information Related Human Factors in the Mellla+ LAR (CACs MF8864 and MF8865, EPID: L-2016-LLA-0009) ML18067A1032018-03-0808 March 2018 NRR E-mail Capture - Brunswick Unit 1 and Unit 2 Request for Additional Information Related Human Factors in the Mellla+ LAR (CACs MF8864 and MF8865, EPID: L-2016-LLA-0009) ML18010A0502018-01-0505 January 2018 E-mail Re. Brunswick Units 1 and Unit 2 - Request for Additional Information Related to the Mellla+ LAR (CACs MF8864 and MF8865) ML18010A0512018-01-0505 January 2018 Unit 2 - Request for Additional Information Related to the Mellla+ LAR (CACs MF8864 and MF8865) (Nonproprietary) ML17339A9132017-12-0505 December 2017 NRR E-mail Capture - Brunswick Unit 1 and Unit 2 Request for Additional Information Related the Exigent Amendment Request for One-Time Extension of EDG Completions Time - Human Factors (EPID: L- 2017- LLA- 0398) ML17339A0702017-12-0404 December 2017 NRR E-mail Capture - Brunswick Unit 1 and Unit 2 Request for Additional Information Related the Exigent Amendment Request for One-Time Extension of EDG Completions Time - Electrical Engineering (EPID: L- 2017- LLA- 0398) ML17317B0022017-12-0404 December 2017 Request for Additional Information Related to License Amendment Request to Revise Technical Specifications to Adopt TSTF-542, Revision 2 (CAC Nos. MF9905 and MF9906; EPID L-2017-LLA-0242) ML17339A0732017-12-0404 December 2017 NRR E-mail Capture - Brunswick Unit 1 and Unit 2 Request for Additional Information Related the Exigent Amendment Request for One-Time Extension of EDG Completions Time - PRA (EPID: L- 2017- LLA- 0398) ML17328A4872017-11-24024 November 2017 Unit 2 - Request for Additional Information Related the Emergency Amendment Request for One-Time Extension of EDG Completions Time ML17275A2772017-10-0202 October 2017 E-mail, Request for Additional Information Related Containment Accident Pressure in the Mellla+ LAR (CAC Nos. MF8864 and MF8865) (Non-Proprietary) ML17192A4842017-07-11011 July 2017 NRR E-mail Capture - Duke Energy Fleet RAIs Alternative for Reactor Pressure Vessel Flange Threads Examination (MF9513 to MF9521) ML17082A3042017-03-0909 March 2017 NRR E-mail Capture - Brunswick Unit 1 and Unit 2 Request for Additional Information Related Containment Accident Pressure in the Mellla+ LAR (CACs MF8864 and MF8865) ML17037A0022017-02-0303 February 2017 NRR E-mail Capture - Brunswick Unit 1 and Unit 2 Request for Additional Information Related to LAR to Modify the TS Requirements for End States Associated with the Implementation of the Approved TSTF Traveler TSTF-423-A (MF8466 and MF8467) ML16020A2632016-01-20020 January 2016 Brunswick Steam Electric Plant - Notification Of Inspection And Request For Information 2023-07-19
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Text
Code of Federal Regulations
DRAFT Enclosure SECOND ROUND REQUESTS FOR ADDITIONAL INFORMATION RELATED TO LICENSE AMENDMENT REQUEST TO ADOPT 10 CFR 50.69, "RISK-INFORMED CATEGORIZATION AND TREATMENT OF STRUCTURES, SYSTEMS, AND COMPONENTS FOR NUCLEAR POWER REACTORS" DUKE ENERGY PROGRESS, LLC BRUNSWICK STEAM ELECTRIC PLANT, UNITS 1 AND 2 DOCKET NOS. 50-325 AND 50-324
1.0 BACKGROUND
By letter dated January 10, 2018 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML18010A344), as supplemented by letter dated November 2, 2018 (ADAMS Accession No ML18306A523), Duke Energy Progress, LLC (Duke Energy, the licensee), submitted a license amendment request (LAR) for Brunswick Steam Electric Plant (BSEP), Units 1 and 2. The proposed amendment would modify the licensing basis to allow for the implementation of the provisions of Title 10 of the Code of Federal Regulations (10 CFR), Section 50.69, "Risk-informed categorization and treatment of structures, systems, and components for nuclear power plants," and provide the ability to use probabilistic risk assessment (PRA) models, namely the internal events PRA, internal flooding PRA (IFPRA), internal fire PRA (FPRA), high winds PRA (HW PRA), and external flooding PRA (XF PRA) for the proposed 10 CFR 50.69 categorization process.
Regulatory Guide (RG) 1.201, Revision 1, "Guidelines for Categorizing Structures, Systems, and Components in Nuclear Power Plants According to their Safety Significance," May 2006 (ADAMS Accession No. ML061090627), endorses, with regulatory positions and clarifications, the Nuclear Energy Institute (NEI) guidance document NEI 00-04, Revision 0, "10 CFR 50.69 SSC [Structure, System, and Component] Categorization Guideline," July 2005 (ADAMS Accession No. ML052910035), as one acceptable method for use in complying with the requirements in 10 CFR 50.69. Both RG 1.201 and NEI 00-04 cite RG 1.200, "An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed Activities," February 2004 (ADAMS Accession No. ML040630078), which endorses industry consensus PRA standards, as the basis against which peer reviews evaluate the technical acceptability of a PRA. Revision 2 of RG 1.200 issued March 2009 is available at ADAMS Accession No. ML090410014.
Section 3.1.1 of the LAR states that Duke Energy will implement the risk categorization process of 10 CFR 50.69 in accordance with NEI 00-04, Revision 0, as endorsed by RG 1.201. However, the licensee's LAR as supplemented does not contain enough information for the U.S. Nuclear Regulatory Commission (NRC) staff to determine if the licensee has implemented the guidance appropriately in NEI 00-04, as endorsed by RG 1.201, as a means to demonstrate compliance with all of the requirements in 10 CFR 50.69, including technical adequacy of the PRA models. The NRC staff has developed the following requests for additional information (RAIs) in order to complete its assessment. 2.0 REQUEST FOR ADDITIONAL INFORMATION PRA RAI 8 Addition of FLEX to the PRA Model
The response to PRA RAI 8 confirmed that FLEX equipment, specifically diesel generators, cooling pumps, and instrument air compressors are incorporated in the PRA models to be used for the 10 CFR 50.69 SSC categorization process. The response identified that the failure rates for these components use the generic NUREG/CR-6928 (ADAMS Accession No. ML070650650) data for other components, that each component requires operator action(s) to meet its functional requirement, and that the failure rates for the associated actions are calculated using the Electric Power Research Institute (EPRI) human reliability analysis (HRA) calculator. In addition, the licensee stated that the addition of FLEX modeling moved the station blackout (SBO) accident sequence from the risk-significant category (top 95% contributor to core damage) to the non-risk significant category.
As noted in PRA RAI 8, the NRC memorandum dated May 30, 2017, "Assessment of the Nuclear Energy Institute 16-06, 'Crediting Mitigating Strategies in Risk-Informed Decision Making,' Guidance for Risk-Informed Changes to Plants Licensing Basis" (ADAMS Accession No. ML17031A269), provides the NRC's staff assessment of challenges to incorporating FLEX equipment into a PRA model used for risk-informed applications. This memorandum provides specific guidance related to FLEX equipment failure rates, operator action probability calculations, and PRA upgrades when used for risk-informed applications.
Please address following:
- a. Regarding component failure data the November 2, 2018, response states that NUREG/CR-6928 generic parameter estimates were used for the FLEX diesel generators (FLEX-DGs), FLEX pumps, and FLEX air compressors since plant-specific data is limited. For the FLEX-DGs, the response states that these components use the failure rates of the safety-related emergency diesel generators (EDGs) since, "they are expected to be as reliable as the EDGs."
The ASME/ANS PRA Standard Capability Category II (CC-II) for supporting requirement (SR) DA-D2 that "if neither plant-specific data nor generic parameter estimates are available for the parameter associated with a specific basic event, USE data or estimates for the most similar equipment available, adjusting if necessary to account for differences. Alternatively, USE expert judgment and document the rationale behind the choice of parameter values."
The NRC staff notes EDGs conduct several test runs in a year and operate for several hours with substantial electrical load to verify their reliability. It is unclear if the FLEX-DGs conduct the same rigorous testing as the EDGs to verify their reliability and therefore it is unknown whether the FLEX-DGs are sufficiently similar to EDGs to warrant uses of EDG generic data. If it cannot be demonstrated in the response to PRA RAI 8-1, subpart c, below, that the uncertainty associated with crediting the flex equipment is not expected to impact the categorization, provide the following:
- i. A justification that the failure rates for safety-related diesel generators can be used for the FLEX-DGs. Include in this discussion the similarities between EDGs and FLEX-DGs regarding installation, training, operation, maintenance, environmental controls, and testing, and how each of these items impact the reliability of the diesel generator.
ii. Develop a failure rate estimate that meets the requirements of the ASME/ANS PRA Standard (e.g., SR DA-D2). Include in this discussion any adjustments made to the generic failure rates due to differences and the rationale used to base those adjustments (provide actual FLEX component failure rates used in the PRA model).
iii. Alternatively to part i and ii, propose a mechanism to develop the FLEX component failure rates in accordance with the ASME/ANS PRA Standard and incorporate them into the PRA models used for the 10 CFR 50.69 SSC categorization process, provide a sensitivity study as part of the suite of sensitivity studies that are included in the categorization process described in NEI 00-04 (e.g., Table 5-2) that can address this uncertainty, or remove credit for the FLEX DGs in the PRA model used for the 10 CFR 50.69 categorization.
- b. Regarding the methodology used to determine the human failure event (HFE) probabilities the, November 2, 2018, response stated that they were evaluated per ASME/ANS PRA Standard SR HR-G3. The licensee stated that the EPRI HRA Calculator was used to quantify the events, explicitly addressing all performance shaping factors identified in HR-G3. However, the EPRI HRA calculator has no directly applicable options explicitly to cover actions like transportation of equipment, or installation of portable hoses and cables. The NRC staff notes that using surrogates for specific actions or engineering judgment to estimate the failure probability does not adequately address the elements needed for a technically acceptable human reliability analysis described in the ASME/ANS PRA Standard. Until gaps in the human reliability analysis methodologies are addressed by improved industry guidance, human error probabilities (HEPs) associated with actions for which the existing approaches are not explicitly applicable should be submitted to the NRC for review. If it cannot be demonstrated in the response to PRA RAI 8-1, subpart c, below, that the uncertainty associated with crediting the flex equipment is not expected to impact the categorization, provide the following:
- i. The HEP analysis for the operator actions related to the employment of FLEX equipment. Include in this discussion how each HFE was adjusted to address the gaps in the methodology and the rationale for each judgement, and a discussion of how the FLEX HFE probabilities compare to similar operator actions performed outside the main control room with the same number of execution steps.
ii. Alternatively to part i, propose a mechanism to develop the FLEX operator HEP values that reflect the gap in methodology and incorporate them into the PRA models used for the 10 CFR 50.69 SSC categorization process, provide a sensitivity study as part of the suite of sensitivity studies that are included in the categorization process described in NEI 00-04 (e.g., Table 5-2) that can address this uncertainty, or remove credit for FLEX operator HEPs in the PRA model used for 10 CFR 50.69 categorization
- c. Regarding the impact of FLEX to the risk insights the November 2, 2018, response stated that the inclusion of FLEX in the PRA model moved the SBO sequence from the risk-significant category to the non-risk significant category. In order for any new risk-informed application that has incorporated mitigating strategies (FLEX) to meet the guidance of RG 1.200, the licensee should either perform a focused-scope peer review of the PRA model or demonstrate that none of the following criteria is satisfied:
(1) Use of a new methodology, (2) Change in scope that impacts the significant accident sequences or the significant accident progression sequences, or (3) Change in capability that impacts the significant accident sequences or the significant accident progression sequences.
The addition of mitigating strategies into a PRA model is considered a change in scope/capability. Based on the licensee's response to PRA RAI 8, subpart d, the addition of mitigating strategies to the Brunswick internal events PRA impacted a significant accident sequence (SBO drops out of top 95% contributor and would no longer be considered a significant accident sequence) and therefore would be considered an upgrade in accordance with the ASME/ANS PRA standard as endorsed by RG 1.200. Provide the following:
- i. Clarify how including FLEX in the PRA is expected to impact the categorization. Specifically, whether and how including FLEX will change the risk-significance of non-FLEX SSCs and whether the FLEX SSCs will be categorized as parts of other systems or as a stand-alone system.
ii. If a significant impact is expected and the FLEX models are retained in the PRA, propose a mechanism to ensure that a focused-scope peer review is performed on the model changes associated with incorporating mitigating strategies, and associated facts and observations (F&Os) are resolved to Capability Category II prior to implementation of the 10 CFR 50.69 SSC categorization process. The peer review should address the issues raised in parts (a) and (b) of this RAI.
iii. Alternatively, remove credit for FLEX equipment and strategies in the PRA models used for the 10 CFR 50.69 SSC categorization process.
PRA RAI 14 Wind Generated Missile Hazard Development
The licensee's response to PRA RAI 14 provides information justifying not using a plant-specific methodology for determining the frequency of damage resulting from missiles generated by high-winds and tornadoes. The response explains that "about 60% of the variance in missile hit probability is explained" by the licensee's approach. Item 3a in the response to PRA RAI 17.a states that the licensee's approach is "assumed to provide reasonable estimates of missile fragilities." The response to PRA RAI 14 states that the assumption is considered "key" per NUREG-1855, "Guidance on the Treatment of Uncertainties Associated with PRAs in Risk-Informed Decisionmaking", Revision 1 (ADAMS Accession No. ML17062A466). Further, the response to PRA RAI 14 states that the use of the sensitivity study required by Section 8.1 of NEI 00-04, "10 CFR 50.69 SSC Categorization Guideline" (ADAMS Accession No. ML052910035), and performance monitoring of low safety significant (LSS) SSCs as required by 10 CFR 50.69(e)(3), as discussed in the response to PRA RAI 17.b, is appropriate to address the "key" assumption of using the non-site-specific high wind missile analysis methodology. The licensee's response to PRA RAI 24.a states that the sensitivity will be performed by increasing the random failure probability of all LSS components by a factor of 3 in the HW PRA model and that "probability of the wind-induced failure events associated with the LSS components" will not be increased. Consequently, no changes to the missile impact failure probability will be included as part of the risk sensitivity study and that failure mode will not be part of the risk sensitivity study. Therefore, it is unclear how the proposed approach (i.e.,
increasing random failures in the HW PRA model by a factor of 3) will address the "key" assumption associated with the use of the licensee's non-plant-specific high wind missile analysis methodology.
Justify how changes to the random failure probability of LSS components will address the "key" assumption of using the non-plant-specific high wind missile analysis methodology in the context of this application. Alternately, propose an approach that will directly address the cited "key" assumption.
PRA RAI 17 External Flood and High Winds Key Assumptions and Sources of Uncertainty
The licensee's response to PRA RAI 17.a includes an external flooding (XF) event associated with the 23 feet (ft.) still water flood as an assumption for the licensee's XF PRA and the response to PRA RAI 17.b considers it to be a "key" assumption. The response to PRA RAI 17.b discusses the use of the sensitivity study discussed in Section 8.1 of NEI 00-04 and performance monitoring of LSS SSCs as required by 10 CFR 50.69(e)(3) as being appropriate to address key uncertainties and assumptions. The licensee's response to PRA RAI 24.a states that the sensitivity will be performed by increasing the random failure probability of all LSS components in the XF PRA by a factor of 3. Therefore, events associated with the 23 ft. still water flood will not be included as part of the XF PRA.
PRA RAI 16 requested a description of how sufficient data points for the XF hazard were determined to capture the plant response at different flooding elevations. The licensee's response states that a cliff-edge effect, which is caused by the failure of diesel generators, in the plant response occurs at an elevation of 23 ft. and that the majority of plant risk in response to external flood events occurs at an elevation at and above 20 ft. but below 23 ft. As noted by the licensee's response, the plant response will be different at 23 ft. as compared to 20 ft. Further, the failure of the diesel generators at 23 ft. can affect this application (e.g., SSCs, such as the Severe Accident Mitigation Alternatives (SAMA) diesel generators, becoming high safety significant) which can be missed if that flood elevation is not quantified as part of the base XF PRA. In light of the above discussion and in the context of this application, discuss why excluding the 23 ft. flood does not identify unique risk significant SSCs and consequently does not impact this application. Alternately, justify how changes to the random failure probability of LSS components will address the "key" assumption related to the plant response at the 23 ft. flood in the context of this application. The response should propose, as appropriate, how two different importance measures for an SSC that would result from the quantification of the PRA model at the 20 ft. and 23 ft. flood elevations will be combined to develop representative importance measures.
PRA RAI 22 Importance Measure Calculation and Categorization of Non-Aligned Components PRA RAI 22.b requested information on how the integrated importance measures will be calculated for HW and XF basic events that may not align directly with basic events in other PRA models. A discussion of the treatment of implicitly modeled components in the HW and XF PRA models in the categorization process was also requested (item ii in PRA RAI 22.b). The licensee's response included a discussion of the importance measure calculation for a component that is credited in one hazard model, but not in all (or any) of the other models. However, the licensee did not provide any discussion on the treatment of implicitly modeled components in the response.
Discuss how implicitly modeled components in the HW and XF PRA models will be captured and treated in the categorization process.