ML21288A331

Summary of October 14, 2021, Public Meeting with SNC, Inc., Regarding Proposed LAR to Modify the TSs to Increase Containment Peak Pressure to Address Several Nuclear Safety Advisory Letters L-2021-LRM-0097

ML21288A331
Person / Time
Site:	Farley
Issue date:	11/04/2021
From:	Stephanie Devlin-Gill Plant Licensing Branch II
To:	Gayheart C Southern Nuclear Operating Co
Devlin-Gill S, NRR/DORL/LPL2-1, 415-5301
References
EPID L-2021-LRM-0097
Download: ML21288A331 (6)

Text

November 4, 2021

LICENSEE: Southern Nuclear Operating Company, Inc.

FACILITY: Joseph M. Farley Nuclear Plant, Units 1 and 2

SUMMARY

OF OCTOBER 14, 2021, PUBLIC MEETING WITH SOUTHERN NUCLEAR OPERATING COMPANY, INC., REGARDING A PROPOSED LICENSE AMENDMENT REQUEST TO MODIFY THE TECHNICAL SPECIFICATIONS TO INCREASE CONTAINMENT PEAK PRESSURE TO ADDRESS SEVERAL NUCLEAR SAFETY ADVISORY LETTERS AT THE JOSEPH M. FARLEY NUCLEAR PLANT, UNITS 1 AND 2 (EPID NO. L-2021-LRM-0097)

On October 14, 2021, an Observation Public Meeting was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of Southern Nuclear Operating Company, Inc. (SNC, the licensee). The purpose of the meeting was for SNC to describe its plan to submit a license amendment request (LAR) to propose modifications to the Joseph M. Farley, Units 1 and 2 (Farley), Technical Specifications (TSs) to increase containment peak pressure to address several Nuclear Safety Advisory Letters (NSALs).

A list of attendees is provided as an Enclosure.

On September 28, 2021 (Agencywide Docum ents and Access Management System (ADAMS)

Accession No. ML21272A196), the meeting was noticed on the NRC public webpage for the meeting to be held on October 14, 2021.

The SNC presented slides contained in ADAMS Accession No. ML21280A001.

Introduction

The NRC staff opened the meeting with introductory remarks and introduction of the attendees.

The SNC personnel discussed the following topics: (1) Background, (2) Proposed License Amendment Request, (3) Analysis, (4) Plant Impacts of Change, and (5) Precedent.

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Background===

The SNC personnel stated that it would request a license amendment to change the Farley TSs to increase containment peak pressure to address several NSALs. The changes proposed by SNC reflect updated calculations of the Loss of Coolant Accident (LOCA) mass and energy (M&E) releases and corresponding containment responses. The proposed changes address issues raised in the Westinghouse NSALs listed below. The NSALs identified modeling and

material property errors in the analyses for the mass and energy releases and, consequently, the errors affected the predicted containment responses.

NSAL 14-2 "Westinghouse Loss-of-Coolant Accident Mass and Energy Release Calculation Issue for Steam Generator Tube Material Properties," March 31, 2014.

NSAL 11-5 "LOCA Mass and Energy Release Calculation Issues" July 25, 2011 (ADAMS Accession No. ML13239A479).

NSAL 06-6 "LOCA Mass and Energy Release Analysis," June 6, 2006.

Proposed License Amendment Request

The SNC personnel said that the proposed LAR would change the Farley TS 5.5.17, Containment Leakage Rate Testing Program as follows:

Current TS 5.5.17 The peak calculated containment internal pressure for the design basis loss of coolant accident, Pa, is 43.8 psig.

Proposed TS 5.5.17 The peak calculated containment internal pressure for the design basis loss of coolant accident, Pa, is 45 psig.

The SNC personnel stated that other licensees have proposed similar changes to address the issues raised in the Westinghouse NSALs. The NRC has approved the following on a plant-specific basis (1) V. C. Summer Nuclear Station (ADAMS Accession Nos. ML18141A668) and (2) Millstone Power Station, Unit 3 (ADAMS Accession Nos. ML14073A055).

The SNC stated that its revised LOCA M&E release calculation uses the methodology described in WCAP-10325-P-A1, which is consistent with that used in the current licensing basis. The licensee stated that the inputs are revised to reflect the modeling and material property errors identified in the NSALs and that the analyses are performed in the same manner as the current analysis of record described in the Farley Updated Final Safety Analysis Report.

The SNC personnel stated that it plans to submit the LAR in November 2021, and request that the NRC staff complete its review within a one-year review period.

NRC Questions to SNC

The NRC staff asked questions of SNC and requested that SNC provide clarifications in its submittal.

On slides 11 and 13, the NRC staff asked SNC for an explanation and justification for the decrease in the refueling water storage tank (RWST) maximum water temperature and the revision to the post-LOCA service water pond te mperature calculation. The NRC staff asked if those changes were made for the purpose of the analysis in the proposed LAR, or were they changed for the purpose of another analysis.

1 Westinghouse LOCA Mass and Energy Release Model for Containment Design - March 1979 Version, WCAP-10325-P-A, May 1983 (Proprietary), WCAP-10326-A (Nonproprietary).

On slide 12, SNC states that the containment pressure analyses was performed using the GOTHIC computer program, version 8.1. The NRC staff asked what version of the GOTHIC computer program was used in SNCs current analysis. SNC stated that its current analysis uses version 6.0 of the GOTHIC computer program. The NRC staff requested that in the proposed LAR, SNC describe any limitations of using GOTHIC computer code and propose resolution.

The NRC staff inquired about the response of the c ontainment sump temperatures and whether they bound the change in analyses. SNC responded that the response of the containment sump temperature is not currently part of its draft submittal, however the changes in sump temperatures are included in the GOTHIC computer model. The NRC staff requested that the LAR describe any changes in containment sump temperatures and changes in net positive suction head (NPSH) for the pumps that draw water from the sump during the LOCA sump recirculation mode.

The NRC staff asked questions about how the cont ainment wall temperatures are affected by the changes proposed by SNC. Specifically, the NRC staff asked if SNC compared any changes in containment wall temperature to the designed structural wall temperature. SNC stated that heat sinks, such as the containment wall, are part of the GOTHIC computer model and were considered during one of SNCs review processes under Title 10 of the Code of Federal Regulation, (10 CFR) Section 50.59, Changes, tests and experiments, and SNC does not plan to submit those for review within t he proposed LAR. The NRC staff requested that any changes in the containment heat sinks from the current analysis be included in SNCs LAR submittal with justification.

The NRC staff questioned the effects of SNCs proposed change on the dose analysis as it relates to RWST back leakage. SNC said they looked at this during a 10 CFR 50.59 process and determined that the impact on back leakage into RWST was insignificant.

On slide 18, 19, and 20, the NRC staff asked if the change in temperature and pressure proposed by SNC effects any other environmental parameters for environmental qualification (EQ) of electrical equipment. SNC stated that the only EQ parameters affected by the proposed change are the pressure and temperature. The NRC staff also asked if SNC analyzed for the required margins for EQ and whether the proposed changes affected the EQ margin. SNC acknowledged the staffs question and stated that they understood it and would follow-up. The NRC staff requested that this information be included in SNC LAR submittal.

The SNC said it understood and would consider t he NRC staffs comments and questions as it develops its submittal.

Public Questions to NRC

There was one member of the public in attendance. No questions or comments were received from the public.

Closing

The NRC staff made no regulatory decisions during the meeting.

Once received, the NRC staff will perform a thorough review of the proposed LAR and make any regulatory decisions in writing in a timely manner.

Please direct any inquiries to me at 301-415-5301 or stephanie.devlin-gill@nrc.gov.

/RA/

Stephanie Devlin-Gill, Project Manager Plant Licensing Branch, II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Docket Nos. 50-348 and 50-364

Enclosure:

List of Attendees

cc w/encls: Listserv

LIST OF ATTENDEES OCTOBER 14, 2021, PUBLIC MEETING WITH SOUTHERN NUCLEAR COMPANY REGARDING A PROPOSED LICENSE AMENDMENT REQUEST JOSEPH M. FARLEY NUCLEAR PLANT, UNITS 1 AND 2

ATTENDEE REPRESENTING

Clint Ashley U.S. Nuclear Regulatory Commission (NRC)

Santosh Bhatt NRC Jorge Cintron-Rivera NRC Stephanie Devlin-Gill NRC Raul Hernandez NRC Matthew McConnell NRC Peter Meier NRC John Parillo NRC Ahsan Sallman NRC Bradley Chamberlain Southern Nuclear Operating Company (SNC)

Jason Douglass SNC Ryan Joyce SNC Wesley Sparkman SNC Elizabeth Sundstrom SNC Kent Bonadio Westinghouse Patricia Furio ENERCON Kevin W. Hicks Alabama State Department of Public Health, Office of Radiation Control

Enclosure

ML21288A331 OFFICE NRR/DORL/LPL2-1/PM NRR/DORL/LPL2-1/LA NRR/DSS/SNSB/BC

NAME SDevlin-Gill KGoldstein SKrepel

DATE 10/14/2021 10/22/2021 11/01/2021 OFFICE NRR/DSS/SCPB/BC NRR/DSS/STSB/BC(A) NRR/DRA/ARCB/BC NAME BWittick NJordan KHsueh DATE 11/03/2021 11/03/2021 11/01/2021 OFFICE NRR/DEX/ELTB/BC NRR/DORL/LPL2-1/BC NRR/DORL/LPL2-1/PM NAME JJohnston MMarkley SDevlin-Gill DATE 11/01/2021 11/04/2021 11/04/2021