ML25051A270
| ML25051A270 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 02/25/2025 |
| From: | Samson Lee Plant Licensing Branch IV |
| To: | Gerfen P Pacific Gas & Electric Co |
| Lee S, 301-415-3158 | |
| References | |
| EPID L-2024-LLA-0179 | |
| Download: ML25051A270 (1) | |
Text
February 25, 2025 Paula Gerfen Senior Vice President, Generation and Chief Nuclear Officer Pacific Gas and Electric Company Diablo Canyon Nuclear Power Plant P.O. Box 56, Mail Code 104/6 Avila Beach, CA 93424
SUBJECT:
DIABLO CANYON NUCLEAR POWER PLANT, UNITS 1 AND 2 -
REGULATORY AUDIT IN SUPPORT OF REVIEW OF LICENSE AMENDMENT REQUEST TO REVISE TECHNICAL SPECIFICATION 1.1 AND ADD TECHNICAL SPECIFICATION 5.5.21 TO USE ONLINE MONITORING METHODOLOGY (EPID L-2024-LLA-0179)
Dear Paula Gerfen:
By letter dated December 31, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24366A169), Pacific Gas and Electric Company (the licensee) submitted a license amendment request (LAR) for Diablo Canyon Nuclear Power Plant, Units 1 and 2 (Diablo Canyon). The proposed amendments would revise Technical Specification (TS) 1.1, Definitions, and add TS 5.5.21, Online Monitoring Program, to use online monitoring methodology.
The licensee proposes to use online monitoring (OLM) methodology as the technical basis to switch from time-based surveillance frequency for channel calibrations to a condition-based calibration frequency based on OLM results. The proposed amendments are based on the U.S. Nuclear Regulatory Commission (NRC)-approved Analysis and Measurement Services Corporation (AMS) topical report (TR) AMS-TR-0720R2-A, Online Monitoring Technology to Extend Calibration Intervals of Nuclear Plant Pressure Transmitters, August 2021 (ML21235A493).
The NRC staff has identified the need for a regulatory audit to examine the licensees 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 using a licensee-established electronic portal available to NRC staff from approximately March 10, 2025, through June 6, 2025, with formal audit meetings to be scheduled during this period as needed. The NRC staff may extend the audit, if necessary. The detailed audit plan is enclosed with this letter.
P. Gerfen If you have any questions, please contact me at 301-415-3168 or via email at Samson.Lee@nrc.gov.
Sincerely,
/RA/
Samson S. Lee, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-275 and 50-323
Enclosure:
Audit Plan cc: Listserv
Enclosure REGULATORY AUDIT PLAN BY OFFICE OF NUCLEAR REACTOR REGULATION TO SUPPORT REVIEW OF LICENSE AMENDMENT REQUEST TO REVISE TECHNICAL SPECIFICATION 1.1 AND ADD TECHNICAL SPECIFICATION 5.5.21 TO USE ONLINE MONITORING METHODOLOGY PACIFIC GAS AND ELECTRIC COMPANY DIABLO CANYON NUCLEAR POWER PLANT, UNITS 1 AND 2 DOCKET NOS. 50-275 AND 50-323
1.0 BACKGROUND
By letter dated December 31, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24366A169), Pacific Gas and Electric Company (the licensee) submitted a license amendment request (LAR) for Diablo Canyon Nuclear Power Plant, Units 1 and 2 (Diablo Canyon). The proposed amendments would revise Technical Specification (TS) 1.1, Definitions, and add TS 5.5.21, Online Monitoring Program, to use online monitoring methodology.
The licensee proposes to use online monitoring (OLM) methodology as the technical basis to switch from time-based surveillance frequency for channel calibrations to a condition-based calibration frequency based on OLM results. The proposed amendments are based on the U.S.
Nuclear Regulatory Commission (NRC)-approved Analysis and Measurement Services Corporation (AMS) topical report (TR) AMS-TR-0720R2-A, Online Monitoring Technology to Extend Calibration Intervals of Nuclear Plant Pressure Transmitters, August 2021 (ML21235A493).
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, Revision 6, dated July 31, 2020 (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 its 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 2, dated December 30, 2024 (ML24309A281), with exceptions noted within this audit plan.
The NRC staff will perform the audit to support its evaluation of whether the licensees 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 be informed by NUREG-0800, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR [Light-Water Reactor] Editions. The audit will assist the NRC staff with understanding the licensees proposed OLM LAR.
3.0 REGULATORY AUDIT SCOPE AND METHODOLOGY NRCs objectives of the audit are the following:
Gain a better understanding of the detailed calculations, analyses, and bases underlying the LAR and confirm the NRC staffs understanding of the LAR.
Gain a better understanding of plant design features and their implications for the LAR.
Identify any information needed to enable the NRC staffs evaluation of the technical basis used for this application.
Identify any information needed to enable the NRC staffs evaluation of whether the proposed changes challenge design-basis functions or adversely affect the capability or capacity of plant equipment to perform design-basis functions.
Identify questions and requests that may become formal requests for additional information (RAIs) per NRR Office Instruction LIC-115, Processing Requests for Additional Information, Revision 1, dated August 9, 2021 (ML21141A238).
The NRC staff will audit the technical information and methods that the licensee used to determine the impact on the plant, and the licensees evaluation of defense-in-depth.
4.0 INFORMATION AND OTHER MATERIAL NECESSARY FOR THE AUDIT The NRC staff will request information and an audit meeting(s) throughout the audit period. The NRC staff will use an audit items list to identify the information (e.g., methodology, process information, and calculations) to be audited. The NRC staff will provide the final audit items list in the audit summary report, which will be publicly available. The attachment to this audit plan includes the initial audit items list. Throughout the audit period, the NRC staff will provide the licensee 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 the 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 accessible for the NRC staffs review via a web-based portal.
5.0 TEAM ASSIGNMENTS The audit team will consist of the following NRC staff from NRR.
Gilberto Blas Rodriguez, Division of Engineering and External Hazards (DEX)/Instrumentation and Controls Branch (EICB)
Tarico Sweat, Division of Safety Systems (DSS)/Technical Specifications Branch (STSB) 6.0 LOGISTICS To support the review schedule communicated to the licensee when the NRC staff accepted the LAR for technical review, audit activities will be performed remotely and virtually using Microsoft Teams, teleconference, and a web-based portal or other virtual meeting space created by the licensee. The NRC staff information requests and communications with the licensee staff will be coordinated through the NRCs licensing project manager.
A desktop audit will take place from approximately March 10, 2025, through June 6, 2025. 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, approximately, a 3-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. The audit meeting agenda and 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 via an internet-based portal within 5 days of this audit plan. The NRC staff requests that any supplemental information requested be available 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 item is added to its portal by sending an email to the NRC licensing project manager.
7.0 SPECIAL REQUESTS The NRC requests access to requested documents and information 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-protected. 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.
Username and password and/or other web-based portal access information should be provided directly to members of the NRC staff and contractors 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, and issue such RAIs separately from audit-related correspondence. The NRC staff will issue an audit summary report prior to completing its review of the LAR.
Attachment:
Initial Audit Items List
Attachment INITIAL AUDIT ITEMS LIST Item #
Audit Item 1
Analysis and Measurement Services Corporation (AMS) Report DBC2410R0, OLM
[Online Monitoring] Amenable Transmitters Report for Diablo Canyon 2
AMS Report DBC2411R0, OLM Analysis Methods and Limits Report for Diablo Canyon 3
AMS Report DBC2412R0, OLM Drift Monitoring Program Report for Diablo Canyon 4
AMS Procedure OLM2201, Procedure for Online Monitoring Data Retrieval, December 2022 5
AMS Procedure OLM2202, Procedure for Performing Online Monitoring Data Qualification and Analysis, August 2024 6
AMS Report DBC2413R0, OLM Noise Analysis Program Report for Diablo Canyon 7
AMS Procedure NPS1501, Procedure for Noise Data Collection from Plant Sensors, March 2015 8
AMS Procedure NAR2201, Procedure for Performing Dynamic Failure Mode Assessment Using Noise Analysis, August 2024
- concurrence via email NRR-106 OFFICE NRR/DORL/LPL4/PM NRR/DORL/LPL4/LA*
NRR/DEX/EICB/BC*
NRR/DSS/STSB/BC
- NAME SLee PBlechman FSacko SMehta DATE 02/20/2025 02/24/2025 02/20/2025 02/19/2025 OFFICE NRR/DORL/LPL4/BC*
NRR/DORL/LPL4/PM*
NAME TNakanishi SLee DATE 02/25/2025 02/25/2025