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EPID:L-2018-LLA-0233, License Amendment Request to Revise Technical Specification 5.2.2.g and Update Emergency Plan Minimum On-shift Staff Tables (Open) |
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MONTHYEARML18226A1082018-04-10010 April 2018, 9 August 2018 License Amendment Request to Revise Technical Specification 5.2.2.g and Update Emergency Plan Minimum On-shift Staff Tables Project stage: Request RC-18-0091, License Amendment Request - LAR-16-01490 National Fire Protection Association Standard 805 Program Revisions2018-08-29029 August 2018 License Amendment Request - LAR-16-01490 National Fire Protection Association Standard 805 Program Revisions Project stage: Request ML18270A0182018-09-27027 September 2018 NRR E-mail Capture - V. C. Summer, Unit 1 - Acceptance of License Amendment Request Related to NFPA-805 Revision Project stage: Acceptance Review ML18337A4032018-12-0606 December 2018 Request for Additional Information Revise Technical Specification 5.2.2.G and Updating Emergency Plan Minimum On-Shift Staff Tables Project stage: RAI ML18355A4772019-01-0404 January 2019 Request for Additional Information Revise TS 5.2.2.g and Update Emergency Plan Minimum On-Shift Staff Tables Project stage: RAI ML19072A1442019-03-13013 March 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-16-01490 NFPA-805 Program Revisions Project stage: RAI ML19095A6532019-04-0404 April 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information NFPA-805 Program Revisions LAR Project stage: RAI ML19119A3652019-04-29029 April 2019 (Vcsns), Unit 1 - License Amendment Request - LAR-16-01490, NFPA 805 Program Revisions: Response to Request for Additional Information Project stage: Response to RAI ML19179A1262019-06-27027 June 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-16-01490 NFPA-805 Program Revisions Project stage: RAI ML19211D5102019-07-30030 July 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-16-01490 NFPA-805 (Supplement to PRA RAI 03) Project stage: RAI ML19196A2112019-08-0202 August 2019 July 23, 2019, Meeting Summary Regarding National Fire Protection Association 805 Supplement License Amendment Request Project stage: Meeting 2019-03-13
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Category:E-Mail
MONTHYEARML24026A2802024-01-25025 January 2024 Acceptance Review for Virgil C. Summer Relief Requests RR-5-V1, RR-5-V2, and RR-5-V3 (EPIDs L-2023-LLR-0067, L-2023-LLR-0068, and L-2023-LLR-0069) (Email) ML23270B8712023-09-27027 September 2023 NRR E-mail Capture - Draft RAIs for License Amendment Request (LAR) to Revise the Virgil C. Summer Nuclear Station (VCSNS) Unit 1 Emergency Plan (L-2023-LLA-0083) ML23193A9552023-07-12012 July 2023 NRR E-mail Capture - Acceptance Review for VC Summer and Surry Relief Request (L-2023-LLR-0029) ML23186A1392023-07-0505 July 2023 NRR E-mail Capture - Acceptance Review for VC Summer Emergency Plan (EP) License Amendment Request (LAR) (L-2023-LLA-0083) ML23131A1492023-05-10010 May 2023 2023 V.C. Summer Commercial Grade Dedication Inspection Information Request ML23044A3392023-02-13013 February 2023 NRR E-mail Capture - Acceptance Review for Change to Reactor Vessel Surveillance Capsule Schedule (L-2023-LLL-0002) ML23027A0122023-01-26026 January 2023 002 Radiation Safety Baseline Inspection Information Request ML23026A0152023-01-23023 January 2023 NRR E-mail Capture - Feb 14, 2023 Public Meeting with the Dominion Energy to Discuss a Planned Emergency Preparedness Submittal to Relocate the Emergency Operations Facility for the VC Summer Power Station - Dominion Slides ML22263A0502022-09-19019 September 2022 NRR E-mail Capture - Draft Request for Additional Information for Proposed Alternative Request RR-4-26 Extension of Steam Generator Primary Inlet Nozzle Dissimilar Metal Weld Inspection Interval V.C. Summer Unit 1 ML22194A9422022-07-13013 July 2022 NRC 50.59 Inspection (IP 71111.17T) Information Request ML22174A3552022-06-23023 June 2022 NRR E-mail Capture - Acceptance Review for Dominion Fleet LAR to Implement TSTF-554 (L-2022-LLA-0078) ML22173A0292022-06-17017 June 2022 NRR E-mail Capture - Acceptance Review for Summer to Defer Weld Examinations (L-2022-LLR-0052) ML22139A2302022-05-19019 May 2022 NRR E-mail Capture - Acceptance Review for Summer TS 4.6.2.1.d LAR (L-2022-LLR-0060) ML22139A2322022-05-19019 May 2022 NRR E-mail Capture - Acceptance Review for Summer TSTF-491 LAR (L-2022-LLR-0059) ML22084A4052022-03-25025 March 2022 NRR E-mail Capture - Acceptance Review for Summer Dissimilar Metal Weld Inspection Interval (L-2022-LLR-0033) ML22018A0272022-01-18018 January 2022 2022 All RFI Responses - Exercise and Program Inspections - Revl ML21333A1892021-11-29029 November 2021 NRR E-mail Capture - Draft RAI for Summer LAR Relocate Surveillance Frequencies to Licensee Control - RITSTF Initiative 5b, (TSTF-425) ML21253A1352021-09-0808 September 2021 Document Request for VC Summer Nuclear Station - Radiation Protection Inspection - Inspection Report 2021-04 ML21197A0432021-07-15015 July 2021 VCS ISI 2021004 RFI - Combined ML21187A1242021-06-28028 June 2021 10CFR Part 21 Update - Deviation Identified in the Bolting Utilized to Maintain Seismic Qualification ML21173A1782021-06-22022 June 2021 NRR E-mail Capture - Acceptance Review - Summer LAR Unit Staff Qualification Relocation TS to Quality Assurance Program Description (QAPD) ML21145A0222021-05-24024 May 2021 003 Radiation Safety Baseline Inspection Information Request ML21131A0402021-05-11011 May 2021 NRR E-mail Capture - V.C. Summer, Unit 1 - Final RAI for the Spring 2020 RFO Sgtir Review ML21125A1942021-05-0505 May 2021 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit 1 - Acceptance Review (L-2021-LLA-0064) ML21020A0562021-01-20020 January 2021 Email Capture Upcoming V.C. Summer POV Inspection (IP71111.21N.02) Information Request ML20342A1822020-12-0707 December 2020 NRR E-mail Capture - Final RAI for Summer LAR - TS 3.6.4 ML20342A3822020-12-0707 December 2020 NRR E-mail Capture - Final RAIs for Summer Fs LOCA LAR ML20321A2112020-11-16016 November 2020 NRR E-mail Capture - Summer, Unit 1 - Final RAIs for the SG Tube Inspection Report Review ML20316A0122020-11-0404 November 2020 NRR E-mail Capture - V.C. Summer Nuclear Station, Unit 1 - Acceptance Review (L-2020-LLR-0141) ML20302A2032020-10-28028 October 2020 NRR E-mail Capture - V.C. Summer Nuclear Station, Unit 1 - Acceptance Review (L-2020-LLR-0141) ML20260H4262020-09-0303 September 2020 NRR E-mail Capture - Acceptance Review for Fleet Relief Request for Code Case N-885 ML20178A5892020-06-26026 June 2020 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit 1 - Acceptance Review of the Fsloca LAR (L-2020-LLA-0124) ML20178A5932020-06-23023 June 2020 NRR E-mail Capture - VC Summer Unit Alternate Request RR-4-19 ML20178A5912020-06-23023 June 2020 NRR E-mail Capture - VC Summer Unit Alternate Request RR-4-21 ML20149K4262020-05-21021 May 2020 NRR E-mail Capture - V. C. Summer, Unit 1 - Acceptance of License Amendment Request (LAR-20-142) Related to TS 3.6.4, Containment Isolation Valves (L-2020-LLA-0092) ML19218A3742019-08-0606 August 2019 NRR E-mail Capture - Virgil C. Summer, Unit 1 -Acceptance of Relief Request (RR-4-20), Use of Encoded Phased Array Ultrasonic Examination Techniques in Lieu of Radiography ML19214A2732019-08-0202 August 2019 NRR E-mail Capture - Virgil C. Summer, Unit 1 - Acceptance of License Amendment Request to Change Company Name ML19211D5102019-07-30030 July 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-16-01490 NFPA-805 (Supplement to PRA RAI 03) ML19179A1262019-06-27027 June 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-16-01490 NFPA-805 Program Revisions ML19155A2752019-06-0404 June 2019 VC Summer 2019003 Rad Safety Inspection Document Request ML19140A2692019-05-17017 May 2019 Acceptance of Alternative Request (RR-4-23)to Utilize Code Case N-513-4 ML19105B1652019-04-15015 April 2019 NRR E-mail Capture - VC Summer SPRA Review - Clarification Questions on Credit for the Abeyance RCP Seals ML19102A0702019-04-11011 April 2019 NRR E-mail Capture - V.C. Summer, Unit 1: Relief Request (RR-4-22) Verbal Authorization Script ML19095A6532019-04-0404 April 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information NFPA-805 Program Revisions LAR ML19072A1442019-03-13013 March 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-16-01490 NFPA-805 Program Revisions ML19095A6582019-03-0404 March 2019 NRR E-mail Capture - VC Summer SPRA Review - Clarification Questions on Peer Review Findings and Plant Modifications ML19095A6672019-01-30030 January 2019 NRR E-mail Capture - VC Summer SPRA Clarification Questions on Circuit Analysis and Relay Replacement ML19031B4332019-01-29029 January 2019 Email Regarding VC Summer Units 2 & 3 Letter from Santee Cooper on Termination of COL ML19009A1052019-01-0909 January 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-10-02395, TS 3.8.2, D.C. Sources - Operating ML19009A5362019-01-0909 January 2019 NRR E-mail Capture - VC Summer Clarification Question on Fussell-Vesely Values 2024-01-25
[Table view] Category:Request for Additional Information (RAI)
MONTHYEARML23270B8712023-09-27027 September 2023 NRR E-mail Capture - Draft RAIs for License Amendment Request (LAR) to Revise the Virgil C. Summer Nuclear Station (VCSNS) Unit 1 Emergency Plan (L-2023-LLA-0083) ML22263A0502022-09-19019 September 2022 NRR E-mail Capture - Draft Request for Additional Information for Proposed Alternative Request RR-4-26 Extension of Steam Generator Primary Inlet Nozzle Dissimilar Metal Weld Inspection Interval V.C. Summer Unit 1 ML22194A9422022-07-13013 July 2022 NRC 50.59 Inspection (IP 71111.17T) Information Request ML22075A0482022-03-16016 March 2022 V.C. Summer Nuclear Station - Information Request for the Cyber-Security Baseline Inspection, Notification to Perform Inspection 05000395/2022401 ML21333A1892021-11-29029 November 2021 NRR E-mail Capture - Draft RAI for Summer LAR Relocate Surveillance Frequencies to Licensee Control - RITSTF Initiative 5b, (TSTF-425) ML21253A1352021-09-0808 September 2021 Document Request for VC Summer Nuclear Station - Radiation Protection Inspection - Inspection Report 2021-04 ML21154A2792021-06-0303 June 2021 Requalification Program Inspection 05000395/2021003 - Virgil C. Summer Nuclear Station, Unit 1, ML21145A0222021-05-24024 May 2021 003 Radiation Safety Baseline Inspection Information Request ML21131A0402021-05-11011 May 2021 NRR E-mail Capture - V.C. Summer, Unit 1 - Final RAI for the Spring 2020 RFO Sgtir Review ML21020A0562021-01-20020 January 2021 Email Capture Upcoming V.C. Summer POV Inspection (IP71111.21N.02) Information Request ML20342A1822020-12-0707 December 2020 NRR E-mail Capture - Final RAI for Summer LAR - TS 3.6.4 ML20342A3822020-12-0707 December 2020 NRR E-mail Capture - Final RAIs for Summer Fs LOCA LAR ML20321A2112020-11-16016 November 2020 NRR E-mail Capture - Summer, Unit 1 - Final RAIs for the SG Tube Inspection Report Review ML20196L7782020-07-13013 July 2020 Notification of Virgil C. Summer Nuclear Station Design Bases Assurance Inspection U.S. Nuclear Regulatory Commission Inspection Report 05000395/2020010 ML20106E8902020-04-15015 April 2020 Program Inspection RFI ML20056E3042020-02-25025 February 2020 VC Summer 2020-002 Radiation Safety Baseline Inspection Information Request ML19211D5102019-07-30030 July 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-16-01490 NFPA-805 (Supplement to PRA RAI 03) ML19179A1262019-06-27027 June 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-16-01490 NFPA-805 Program Revisions ML19095A6532019-04-0404 April 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information NFPA-805 Program Revisions LAR ML19072A1442019-03-13013 March 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-16-01490 NFPA-805 Program Revisions ML19009A1052019-01-0909 January 2019 NRR E-mail Capture - Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information LAR-10-02395, TS 3.8.2, D.C. Sources - Operating ML18249A1932018-09-0505 September 2018 TS 4.3.3.6 SR LAR - Request for Additional Information ML18225A0932018-08-13013 August 2018 Notification of Inspection and Request for Information ML18218A2622018-08-0101 August 2018 Emergency Preparedness Program Inspection Request for Information ML18066A0002018-03-0808 March 2018 Request for Additional Information Integrated Leak Rate Test Peak Calculated Containment Internal Pressure Change ML18023B0692018-02-15015 February 2018 Request for Additional Information Relief Request (RR-4-13), Use of Risk-Informed Process as an Alternative for the Selection of Class 1 and Class 2 Piping Welds ML17095A2842017-05-11011 May 2017 Request for Additional Information License Amendment Request for Implementation of TSTF-411 (WCAP-15376-P-A), Revision 1 ML17067A5322017-03-0808 March 2017 Notification of Radiation Protection Baseline Inspection and Request for Information ML17059C5382017-02-23023 February 2017 Notification of Inspection and Request for Information ML16302A1252016-11-0808 November 2016 Request for Additional Information License Amendment Request for Implementation of TSTF-411 and WCAP-15376-P-A, Revision 1 RC-16-0112, NRC Request Information Baseline Radiation Safety Inspection2016-07-0707 July 2016 NRC Request Information Baseline Radiation Safety Inspection ML16111A0912016-05-0303 May 2016 Request for Additional Information Regarding the Station Physical Security Plan, Revision 14 ML16097A0812016-04-0808 April 2016 Request for Additional Information ML16064A0332016-03-0303 March 2016 NRR E-mail Capture - Request for Additional Information Related to the March 1, 2016, Exigent Amendment Request ML16042A4712016-02-18018 February 2016 Request for Additional Information ML15320A3382015-12-0101 December 2015 Request for Additional Information Regarding License Basis Changes in Steam Generator Tube Rupture Analysis RC-15-0177, Submits LAR-12-04269, License Basis Changes in Steam Generator Tube Rupture Analysis Response to Response for Additional Information2015-11-0505 November 2015 Submits LAR-12-04269, License Basis Changes in Steam Generator Tube Rupture Analysis Response to Response for Additional Information ML15261A0512015-09-22022 September 2015 Request for Additional Information Regarding License Basis Changes in Steam Generator Tube Rupture Analysis ML15118A4592015-05-19019 May 2015 Request for Additional Information Regarding Alternative Request ML15118A3802015-05-0505 May 2015 Request for Additional Information Regarding Snubber Program Alternative Request ML15076A1182015-04-13013 April 2015 Request for Additional Information Regarding License Basis Changes in Steam Generator Tube Rupture Analysis ML15079A0992015-03-26026 March 2015 Request for Additional Information ML14339A0302015-01-0909 January 2015 Request for Additional Information Regarding License Basis Changes in Steam Generator Tube Rupture Analysis ML14268A5162014-10-23023 October 2014 Request for Additional Information Associated with Near-Term Task Force Recommendation 2.1, Seismic Re-evaluation Related to Southeastern Catalog Changes ML14226A2552014-08-29029 August 2014 Request for Additional Information ML14182A4732014-07-11011 July 2014 Request for Additional Information Regarding License Amendment Request to Adopt National Fire Protection Association Standard 805 ML14071A1692014-03-24024 March 2014 Request for Additional Information ML14023A7402014-01-30030 January 2014 (VCSNS) - Request for Additional Information ML13347B0492013-12-19019 December 2013 (VCSNS) - Request for Additional Information ML13340A3772013-12-11011 December 2013 (VCSNS) - Request for Additional Information 2023-09-27
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Text
NRR-DMPSPEm Resource From: Williams, Shawn Sent: Thursday, April 4, 2019 3:26 PM To: MOORE, MICHAEL S Cc: BOUKNIGHT, JUSTIN R ; DALICK, SARA BETH
Subject:
Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information NFPA-805 Program Revisions LAR (EPID No. L-2018-LLA-0233)
Attachments: Summer NFPA LAR RAI 3 4 and 5.docx
Dear Mr. Moore,
By letter dated August 29, 2018 (Agencywide Documents Access and Management System (ADAMS) Accession No.
ML18242A658) South Carolina Electric & Gas Company (SCE&G) submitted a license amendment request for the Virgil C.
Summer Nuclear Station, Unit 1, to make changes to its approved fire protection program (FPP) under 10 CFR 50.48(c). In its LAR, the licensee proposed to make several changes to its FPP including changes to plant modifications, use of performance-based alternatives to the requirements of National Fire Protection Association Standard 805 (NFPA-805), Chapter 3, and several clarifications and editorial corrections.
By e-mail dated March 13, 2019 (ADAMS Accession No. ML19072A144), the U.S. Nuclear Regulatory Commission (NRC) provided three requests for additional information (RAI). Regarding PRA RAI No. 3, on March 18, 2019, SCE&G informed the NRC staff that the abeyance seals were credited in the PRA model. Based on this new information, the attached includes a revised PRA RAI No. 3 and two additional RAIs.
During a clarification call on April 4, 2019, Mr. Bouknight, of your staff agreed that SCE&G would respond to PRA RAI No.
3, 4, and 5 within 45 days of the date of this e-mail, which corresponds to approximately May 20, 2019. PRA RAI No. 1 and 2 should continue to be responded by the original agreed 45 days, which corresponds to approximately April 29, 2019.
Please note that the NRC staff's review is continuing and further requests for information may be developed.
If you have any questions, please contact me at 301-415-1009 or Shawn.Williams@nrc.gov.
Sincerely, Shawn A. Williams, Senior Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No.: 50-395
Enclosure:
Request for Additional Information 1
Hearing Identifier: NRR_DMPS Email Number: 905 Mail Envelope Properties (DM6PR09MB316481444D775895EE9B477790500)
Subject:
Virgil C. Summer Nuclear Station, Unit No. 1 - Request for Additional Information NFPA-805 Program Revisions LAR (EPID No. L-2018-LLA-0233)
Sent Date: 4/4/2019 3:25:39 PM Received Date: 4/4/2019 3:25:40 PM From: Williams, Shawn Created By: Shawn.Williams@nrc.gov Recipients:
"BOUKNIGHT, JUSTIN R " <JUSTIN.BOUKNIGHT@scana.com>
Tracking Status: None "DALICK, SARA BETH " <SARA.DALICK@scana.com>
Tracking Status: None "MOORE, MICHAEL S" <MICHAEL.S.MOORE@scana.com>
Tracking Status: None Post Office: DM6PR09MB3164.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 1968 4/4/2019 3:25:40 PM Summer NFPA LAR RAI 3 4 and 5.docx 34745 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:
Recipients Received:
REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST TO REVISE NATIONAL FIRE PROTECTION ASSOCIATION STANDARD 805 FIRE PROTECTION PROGRAM VIRGIL C. SUMMER NUCLEAR STATION, UNIT NO. 1 DOCKET NO. 50-395 By letter dated August 29, 2018 (Agencywide Document Access and Management System (ADAMS) Package Accession No. ML18242A657), South Carolina Electric and Gas (SCE&G),
submitted a license amendment request (LAR) for the Virgil C. Summer Nuclear Station, Unit 1 (VCSNS), to make changes to its approved fire protection program (FPP) under 10 CFR 50.48(c). In its LAR, the licensee proposed to make several changes to its FPP including changes to plant modifications, use of performance-based alternatives to the requirements of NFPA 805, Chapter 3, and several clarifications and editorial corrections.
Regulatory Guide (RG) 1.200, An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment [PRA] Results for Risk-informed Activities, Revision 2 (ADAMS Accession No. ML090410014), provides guidance for addressing probabilistic risk assessment (PRA) acceptability including addressing the need for the PRA model to represent the as-built, as-operated plant. This regulatory guide provides one approach acceptable to the U.S. Nuclear Regulatory Commission (NRC) for determining the technical acceptability of the PRA model.
Regulatory Guide 1.200 endorses, with certain clarifications and qualifications, Addendum A to the American Society of Mechanical Engineers/American Nuclear Society (ASME/ANS) RA-Sa-2009, "Standard for Probabilistic Risk Assessment for Nuclear Power Plant Applications" ("PRA Standard"). Section 4.2, "Licensee Submittal Documentation," of RG 1.200 states, in part, that the application should discuss the resolution of the open peer review facts and observations (F&Os) that are applicable to the parts of the PRA required for the application.
By e-mail dated March 13, 2019 (ADAMS Accession No. ML19072A144), the NRC issued three requests for additional information (RAI). Regarding PRA RAI No. 3, on March 18, 2019, SCE&G informed the NRC staff that that the abeyance seals were credited in the PRA model.
Based on this information, the below contains a revised RAI No. 3 and two additional RAIs based on NRC staffs review of the F&Os.
PRA RAI 03 (Revised)
In Enclosure 1, Attachment 1 to the licensees letter dated August 29, 2018, the licensee stated that PRA refinements were made to the reactor coolant pump (RCP) seal loss of coolant accident (LOCA) model based on the RCP seal upgrades. The LAR is not clear on whether these refinements go beyond those described in the NFPA 805 LAR, as supplemented (Approved in Amendment No. 199 - ADAMS Accession No. ML14287A289).
a) Describe the PRA refinements to the RCP seal LOCA model and discuss whether the approach was used previously to support the NFPA 805 LAR or in another plant LAR and subsequent amendment and if these changes constitute a PRA upgrade as defined in ASME/ANS RA-Sa-2009, Section 1-5.4, as qualified by RG 1.200, Revision 2. Provide the basis for the conclusion regarding whether the refinements are considered a PRA upgrade.
If the refinements are an upgrade, provide the findings of the peer review(s) performed and associated disposition of the findings as it pertains to the impact on this LAR. Please indicate whether the abeyance seals were credited in the PRA model.
b) If the abeyance seals were credited in the PRA model, then provide one of the following:
i) Describe and justify the PRA methodology used to model the abeyance seals. Describe how crediting the abeyance seals impact the fire PRA results in Table W-3 of LAR Enclosure 1, Attachment 5 (e.g., describe and provide the results of a sensitivity study, including the total transition CDF, LERF, CDF, and LERF, that does not credit the abeyance seals). OR ii) Alternatively to part (i), provide updated risk results in Table W-3 of LAR Enclosure 1, Attachment 5 that does not credit the abeyance seals in the PRA and discuss how the updated risk results align with the risk acceptance guidelines of RG 1.205. Propose a mechanism that ensures an NRC accepted abeyance seal model is available before incorporation of an abeyance seal into the PRA model used for self-approval of post-transition changes.
PRA RAI 04 , Attachment 1, Section 2 of the LAR states the fire PRA (FPRA) was updated for refinements to the internal events PRA (IEPRA). The LAR describes some of these refinements and indicates that a full-scope peer review was performed in June 2016. The LAR is not clear as to whether any refinements were made after the 2016 peer review that could be considered PRA upgrades. Also, the dispositions to F&Os from the 2016 peer review of the IEPRA in LAR , Attachment 8 indicate additional changes may have been made to the IEPRA since the peer review. Therefore, it is uncertain whether the latest IEPRA incorporated in the FPRA meets the PRA acceptability guidance in RG 1.200, Revision 2. The staff requests the licensee provide the following additional information:
a) Describe the changes made to the IEPRA since the full-scope peer review conducted in June 2016. This description should be of sufficient detail to determine whether the changes are considered PRA maintenance or PRA upgrades as defined in ASME/ANS RA-Sa-2009, Section 1-5.4, as qualified by RG 1.200, Revision 2. Include in your discussion: (1) any new methodologies (i.e., summarize the original method in the PRA and the new method); (2) changes in scope that impact the significant accident sequences or the significant accident progression sequences; (3) changes in capability that impact the significant accident sequences or the significant accident progression sequences.
b) For each change described in Part (a) above, indicate whether the change was PRA maintenance or a PRA upgrade, along with justification for this determination.
c) For each PRA upgrade identified in Part (b) above, either:
- i. Provide the findings of the peer review(s) performed on the upgrade and the disposition of the findings as it pertains to the impact on this LAR. OR, ii. Provide sufficient information for NRC staff to compare the technical adequacy of the analysis to RG 1.200, Revision 2, or provide a bounding or sensitivity evaluation of its effect until a focused-scope peer review can be completed.
d) Refinements were made to the IEPRA and internal flooding PRA (IFPRA). It is not clear why the risk values (i.e., CDF, LERF) for these hazards in LAR Enclosure 1, Attachment 5 (page 3) are the same as those for the NFPA 805 LAR. Provide updated IEPRA and IFPRA risk values in LAR Attachment 5 or provide clarification as to why these values remain unchanged from the NFPA 805 LAR.
PRA RAI 05 , Attachment 8 of the LAR provides PRA peer review F&Os and dispositions for the IEPRA and IFPRA. Address the following questions related to the dispositions of the IEPRA F&Os for this LAR:
a) In F&O 2-18 (associated with supporting requirement, SR, HR-F2 of ASME/ANS RA-Sa-2009), the time window for successful completion of human failure events (HFE) (i.e., time available to perform operator actions) is not based on accident sequence based timings.
The F&O provides an example where the operator action to supply alternate AC power (i.e.,
operator action OA_AAC_SBO) is based on an assumption rather than an actual accident sequence timing value. The associated disposition addresses this example by stating alternate AC power was designed to be available in 60 minutes and this time was used as the time required to complete the operator action. The disposition does not seem to address the issue identified by the F&O, because the F&O pertains to the time available to perform operator actions (i.e., system time window), while the disposition addresses the time required to complete the operator action (i.e., the time it takes to perform operator action).
Also, the disposition only addresses the two examples discussed in the F&O; however, these examples may not necessarily represent all instances of this issue as indicated by the peer review teams assessment. Lastly, no basis is provided for the following statement in the disposition and it is not clear what is meant by may be small changes in that statement:
There may be small changes to the HFE values for these items for the Internal Events model but no impact on Fire PRA.
Considering the observations above, explain why resolution of this F&O has no impact on the FPRA and how this resolution impacts the IEPRA.
b) In F&O 4-01 (associated with SR SC-A5 of ASME/ANS RA-Sa-2009), the IEPRA utilizes mission times less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The associated disposition states, [t]he Peer Review team did not fully agree with this approach [(i.e., the approach discussed in the disposition and used in the PRA)] and recommended changing all mission time[s] to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. If adjustments to mission times are found necessary, the closure of this F&O is not expected to have a significant impact on CDF or LERF. The licensees resolution to this F&O is based on an approach that is disagreed upon by the peer review team, and adjustments to mission times can have a significant impact on basic event failure probabilities and the resulting risk. Therefore, it is not clear how resolution of this F&O is not expected to have a significant impact on risk. Considering the observations above, clearly explain why
resolution of this F&O is not expected to have a significant impact on FPRA risk. For example, describe and provide the results of a sensitivity study (such results should include fire plant total CDF, LERF, CDF, and LERF in Table W-3 of LAR Enclosure 1, Attachment
- 5) and discuss how the RG 1.205 risk acceptance guidelines continue to be met.
c) In F&O 4-05 (associated with SR SC-B4 of ASME/ANS RA-Sa-2009), thermal-hydraulic analyses (e.g., MAAP5 runs) and control room simulation runs were used to support success criteria and PRA assumptions; however, use of simulation runs are questionable for the reasons explained in the F&O. The associated disposition does not address use of simulation runs in development of success criteria and PRA assumptions. Explain how simulation runs were used to support development of success criteria and PRA assumptions. Justify how these simulator runs constitutes a thermal-hydraulic analysis and provides an adequate basis to support its use in development of success criteria and PRA assumptions consistent with ASME/ANS RA-Sa-2009, as qualified by RG 1.200, Revision 2.