ML24163A053
| ML24163A053 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 06/14/2024 |
| From: | Dawnmathews Kalathiveettil Plant Licensing Branch II |
| To: | Coleman J Southern Nuclear Operating Co |
| Kalathiveettil, D | |
| References | |
| EPID L-2024-LLA-0017 | |
| Download: ML24163A053 (1) | |
Text
June 14, 2024
Jamie M. Coleman Regulatory Affairs Director Southern Nuclear Operating Co., Inc.
3535 Colonnade Parkway Birmingham, AL 35243
SUBJECT:
EDWIN I. HATCH NUCLEAR PLANT, UNITS 1 AND 2 - REGULAORY AUDIT IN SUPPORT OF REVIEW OF THE LICENSE AMENDMENT REQUEST TO REVISE RENEWED FACILITY OPERATING LICENSES TO ADOPT AN ALTERNATIVE SEISMIC METHOD FOR CATEGORIZATION OF STRUCTURES, SYSTEMS, AND COMPONENTS (EPID: L-2024-LLA- 0017)
Dear Jamie Coleman:
By letter dated February 20, 2024 (Agencywide Documents and Access Management System (ADAMS) Accession No. ML24051A239), Southern Nuclear Operating Company (SNC, the licensee) submitted a license amendment request (LAR) for Edwin I. Hatch Nuclear Plant (Hatch), Units 1 and 2. The proposed LAR w ould modify the licensing basis to implement a change to the approved voluntary 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 reactors. The proposed amendment would incorporate the use of an alternative seismic method into the previously approved 10 CFR 50.69 categorization process in addition to the plant-specific Hatch seismic probabilistic risk assessment.
The U. S. Nuclear Regulatory Commission (NRC) staff has identified the need for a regulatory audit to examine SNCs non-docketed information with the intent to gain understanding, to verify information, or to identify information that will require docketing to support the basis of the licensing or regulatory decision.
The NRC staff will conduct the audit virtually via Teams, potentially using a licensee-established electronic portal available to NRC staff, from approxim ately July 1, through September 30, 2024, with formal audit meetings to be scheduled dur ing this period as needed. The NRC staff reserves the right to extend the audit, if necessary. The detailed audit plan is enclosed with this letter.
J. Coleman
If you have any questions, please contact me at (301) 415-3100 or by e-mail at Dawnmathews.Kalathiveettil@nrc.gov.
Sincerely,
/RA/
Dawnmathews T. Kalathiveettil, Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Docket Nos. 50-321 and 50-366
Enclosures:
- 1) Audit Plan
- 2) Initial Audit Items List
- 3) Audit Questions
cc: Listserv REGULATORY AUDIT PLAN
BY THE OFFICE OF NUCLEAR REACTOR REGULATION
TO SUPPORT THE REVIEW OF THE LICENSE AMENDMENT REQUEST
TO REVISE THE LICENSING BASIS TO
ADOPT AN ALTERNATIVE SEISMIC METHOD FOR
CATEGORIZATION OF STRUCTURES, SYSTEMS, AND COMPONENTS
SOUTHERN NUCLEAR OPERATING COMPANY
EDWIN I. HATCH NUCLEAR PLANT, UNITS 1 AND 2
DOCKET NOS. 50-321 AND 50-366
1.0 BACKGROUND
By letter dated February 20, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24051A239), Southern Nuclear Operating Company (SNC, the licensee) submitted a license amendment request (LAR) for Edwin I. Hatch Nuclear Plant, Units 1 and 2 (Hatch). The proposed amendment m odifies the licensing basis to implement a change to the approved voluntary 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 nucl ear power reactors. The proposed amendment would incorporate the use of an alternative seismic method into the previously approved 10 CFR 50.69 categorization process in addition to the plant-specific Hatch seismic probabilistic risk assessment.
The NRC staff from the Office of Nuclear Reactor Regulation (NRR) has initiated its review of the LAR in accordance with NRR Office Instruction LIC-101, License Amendment Review Procedures (ML19248C539).
2.0 REGULATORY AUDIT BASIS
A regulatory audit is a planned license-or regulation-related activity that includes the examination and evaluation of primarily non-docketed information associated with the LAR. An audit is conducted to gain understanding, to verify information, and to identify information that will require docketing to support the basis of a licensing or regulatory decision. An audit will assist the NRC staff in efficiently conducting it s review and gaining insights to the licensees processes and procedures. Information that the NRC staff relies upon to make the safety determination must be submitted on the docket. This audit will be conducted in accordance with NRR Office Instruction LIC-111, Regulatory Audits, Revision 1, dated October 2019 (ML19226A274), with any exceptions noted within this audit plan.
The NRC staff will perform the audit to support its evaluation of whether SNCs LAR can be approved per Title 10 of the Code of Federal Regulations (10 CFR), Section 50.90, Application for amendment of license, construction permit, or early site permit. The NRC staffs review will
Enclosure 1
be informed by NUREG-0800, Standard Review Plan. The audit will assist the NRC staff with understanding the licensees proposed LAR.
3.0 REGULATORY AUDIT SCOPE AND METHODOLOGY
NRCs objectives of the audit are the following:
Clarification of Hatch plant-specific applicability and variations as compared to the LaSalle 10 CFR 50.69 precedent.
Consideration of licensee experience and results using the seismic PRA in the approved 10 CFR 50.69 categorization process.
Discussion on non-PRA-based qualitative assessments.
Identifying any information needed for NRC to assess whether proposed changes could challenge design-basis functions or adversely affect the capability or capacity of plant equipment to perform design-basis functions.
Identifying questions and information needs that may require formal requests for additional information (RAIs) per NRR Office Instruction LIC-115, Processing Requests for Additional Information (ML21141A238).
4.0 INFORMATION AND OTHER MATERIAL NECESSARY FOR THE AUDIT
The NRC staff will request information and an audi t meeting(s) throughout the audit period. The NRC staff will use an audit items list to identify the information (e.g., methodology, process information, etc.) to be audited. The NRC sta ff will provide the final audit items list as an enclosure to the audit summary report, which will be publicly available. Enclosure 2 describes the initial audit items list and Enclosure 3 describes the initial audit questions.
Throughout the audit period, the NRC staff will provide SNC with audit questions and audit-related requests so that the licensee can better prepare for audit discussions with NRC staff.
Any information accessed through the licensees portal will not be held or retained in any way by NRC staff. The NRC staff requests the licensee to have the requested audit information listed in the audit items list to be readily available and ac cessible for the NRC staffs review either via a Web-based portal or during the audit meeting(s).
5.0 TEAM ASSIGNMENTS
The audit team will consist of t he following NRC staff from NRR.
Dawnmathews Kalathiveettil, Division of Operating Reactor Licensing (DORL)/Plant Licensing Branch 2-1 (LPL2-1)
John G. Lamb, DORL/LPL2-1 Daniel Silverstein, Division of Risk Asse ssment (DRA)/PRA Licensing Branch C (APLC)
Steven Alferink, DRA/APLC Stephanie Garza, DRA/APLC
6.0 LOGISTICS
To support the review schedule communicated to SNC when the NRC staff accepted the LAR for technical review, audit activities will be performed remotely and virtually using Microsoft Teams, teleconference, and potentially a Web-based portal or other virtual meeting space
created by the licensee. The NRC staff informati on requests and communications with licensee staff will be coordinated through the NRCs licensing project manager.
The virtual audit will take place between July 1 and September 30, 2024. The NRCs licensing project manager will inform the licensee of the entrance and exit meeting dates when they are established. The NRC intends to establish a one -day virtual audit meeting via Microsoft Teams on mutually agreeable dates and times, to discuss information needs and questions arising from the NRCs review of the audited items. The NRC staff may change and/or add audit dates and times, or extend the audit, if necessary. A udit meeting agenda and additional questions, if needed, will be sent in advance of the audit meeting.
The NRC staff requests the licensee to have the information referenced in Section 4.0 of this audit plan available and accessible for the NRC staffs review potentially via an internet-based portal at the latest by July 1, 2024, once this audit plan is received. The NRC staff requests that any supplemental information requested be avail able and accessible for the NRC staffs review within 5 days of the date of the NRCs notification to the licensee of the new requests. The NRCs licensing project manager will inform the licensee via routine communications when the NRC staff no longer needs access to the portal. The NRC staff requests the licensee to notify the NRCs licensing project manager when an audit it em is added to its portal by sending an e-mail to the NRC licensing project manager.
7.0 SPECIAL REQUESTS
The NRC requests access to requested documents and information potentially through a Web-based portal that allows the NRC staff and contractors to access documents over the Internet.
The following conditions associated with the online portal must be maintained while the NRC staff and contractors have access to the online portal:
The online portal will be password-protect ed. A separate password will be assigned to each member of the NRC staff and NRC contractors participating in the audit.
The online portal will prevent the NRC participants from printing, saving, downloading, or collecting any information directly from the online portal.
Conditions of use of the online portal will be displayed on the login screen and will require acknowledgment by each user.
Username and password and/or other Web-based portal access information should be provided directly to members of the NRC staff and c ontractors as needed. The NRC licensing project manager will provide the licensee with names and contact information of the NRC staff and contractors participating in the audit. All other communications should be coordinated through the NRC project manager.
8.0 DELIVERABLES
The NRC staff will develop any RAIs, as needed, via NRR Office Instruction LIC-115 and issue such RAIs separately from audit-related co rrespondence. The NRC staff will issue an audit summary report prior to completing its review of the LAR.
INITIAL AUDIT ITEMS LIST
Item # Audit Item 1 Clarification of plant-specific applicability and variations as compared to the LaSalle 10 CFR 50.69 precedent.
2 Consideration of on licensee experience and results using the seismic PRA in the approved 10 CFR 50.69 categorization process.
3 Discussion on non-PRA based qualitative assessments.
Enclosure 2 AUDIT QUESTIONS
REGARDING LICENSE AMENDMENT REQUEST
TO REVISE THE LICENSING BASIS TO
ADOPT AN ALTERNATIVE SEISMIC METHOD FOR
CATEGORIZATION OF STRUCTURES, SYSTEMS, AND COMPONENTS
SOUTHERN NUCLEAR OPERATING COMPANY
EDWIN I. HATCH NUCLEAR PLANT, UNITS 1 AND 2
DOCKET NOS. 50-321 AND 50-366
By letter dated February 20, 2024 (ADAMS Accession No. ML24051A239), SNC submitted a license amendment request (LAR) for Hatch, Units 1 and 2. The proposed LAR would modify the licensing basis to implement a change to the approved voluntary implementation of the provisions of Title 10 of the Code of Federal Regulations (10 CFR), Section 50.69, Risk-informed categorization and treatment of struct ures, systems and components for nuclear power reactors. The proposed amendment would incorporate the use of an alternative seismic method into the previously approved 10 CFR 50.69 categorization process in addition to the plant-specific Hatch seismic probabilistic risk assessment.
The NRC staff has identified the need for a r egulatory audit to examine SNCs non-docketed information with the intent to gain understanding, to verify information, or to identify information that will require docketing to support the basis of the licensing or regulatory decision. Staff are providing the questions below to aid discussion during the audit.
Question 1
Section 3.1.1, Categorization Process Using Alternative Seismic Method for Tier 2 Sites, of the LAR enclosure asserts that the licensee will follow the same alternative seismic approach in the 10 CFR 50.69 categorization process for Hatch as that approved by the NRC staff for LaSalle County Station (LaSalle) with the following two clarifications.
- 1. The Hatch LAR cites EPRI Report 3002017583, Alternative Approaches for Addressing Seismic Risk in 10 CFR 50.69 Risk-Informed Categorization, dated February 2020 (ML21082A170) with the markups provided in attachment 2 of the LaSalle 10 CFR 50.69 request for additional information (RAI) responses dated October 16, 2020 (ML20290A791) and January 22, 2021 (ML21022A130), whereas the 10 CFR 50.69 categorization process approved by the NRC staff for LaSalle cited non-docketed EPRI 3002012988, Alternative Approaches for Addressing Seismic Risk in 10 CFR 50.69 Risk-Informed Categorization, dated July 2018.
- 2. The Hatch LAR incorporates the LaSalle 10 CFR 50.69 RAI response dated October 1, 2020 (ML20275A292) that addresses process issues associated with the proposed alternative seismic approach, but it specifically excludes the response to LaSalle RAI APLC 50.69-RAI No. 12 because it addresses external events that are outside the scope of this request.
Enclosure 3
A recent Brunswick LAR dated August 17, 2023 (ML23229A456) also asserts how the applicant will follow the same alternative seismic approach in the 10 CFR 50.69 categorization process as that approved by the NRC staff for LaSalle with the following two exceptions.
- 1. The site-specific LaSalle information (e.g., seismic capacity discussions, etc.) from the LaSalle 10 CFR 50.69 LAR and other LaSalle licensing responses do not apply.
- 2. The configuration control checklist described in the LaSalle submittal implies that a specific checklist was developed for 10 CFR 50.69 reviews. The applicant did not incorporate this checklist, but rather described its own configuration control and periodic review processes.
Please describe if the proposed amendment incorporates site-specific LaSalle information in the approved LaSalle 10 CFR 50.69 LAR and RAI responses.
- a. If the proposed amendment incorporates site-specific LaSalle information in the approved LaSalle 10 CFR 50.69 LAR and RAI responses, describe the impact of incorporating site-specific LaSalle information in the proposed Hatch 10 CFR 50.69 categorization process.
- b. If the proposed amendment does not incorporate site-specific LaSalle information in the approved LaSalle 10 CFR 50.69 LAR and RAI responses, clarify where an exception to the site-specific LaSalle information is addressed in the LAR.
Question 2
The LAR states, in part, that the proposed amendment incorporates the use of an alternative seismic method in addition to the peer-reviewed, plant-specific seismic probabilistic risk assessment (SPRA) into the previously approved 10 CFR 50.69 categorization process, which was approved on June 26, 2020 (ML20077J704).
Please address the following:
- a. Discuss if the approved 10 CFR 50.69 categorization process has identified any Structures, Systems, and Components (SSCs) as high safety significance (HSS) solely from the SPRA. If the approved 10 CFR 50.69 categorization process has identified any SSC as HSS solely from the SPRA:
- i. Provide a list of these SSCs.
ii. Discuss if these SSCs would still be identified as HSS using the proposed alternative approach.
- b. Discuss if the approved 10 CFR 50.69 categorization process has identified any unique risk insights using the SPRA and how these insights are captured by the case studies in EPRI Report 3002017583 and consequently, the proposed alternate seismic approach.
Question 3
Section 3.1.1 of the enclosure to the LAR states, in part:
For HSS SSCs uniquely identified by the Hatch PRA models but having design-basis functions during seismic events or functions credited for mitigation and prevention of severe accidents caused by seismic events, these will be addressed using non-PRA based qualitative assessments in conjunction with any seismic insights provided by the PRA.
Division of Risk Assessment (DRA)/PRA Licensing Branch C (APLC) requests a discussion on how non-PRA based qualitative assessments will be used in conjunction with seismic insights provided by the PRA as part of the proposed alternate seismic approach.
ML24163A053 OFFICE NRR/DORL/LPLII-1/PM NRR/DORL/LPLII-1/LA NRR/DRA/APLC/BC NAME DKalathiveettil KGoldstein SVasavada (AGrady For)
DATE 06/07/2024 06/11/2024 06/13/2024 OFFICE NRR/DORL/LPLII-1/BC NRR/DORL/LPLII-1/PM NAME MMarkley DKalathiveettil DATE 06/12/2024 06/14/2024