ML23248A224
| ML23248A224 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 09/07/2023 |
| From: | Shilpa Arora Plant Licensing Branch III |
| To: | Peter Dietrich DTE Electric Company |
| Arora S | |
| References | |
| EPID L-2023-LLA-0092 | |
| Download: ML23248A224 (1) | |
Text
September 7, 2023 Mr. Peter Dietrich Senior Vice President and Chief Nuclear Officer DTE Electric Company Fermi 2 - 260 NOC 6400 North Dixie Highway Newport, MI 48166
SUBJECT:
FERMI UNIT 2 - REGULATORY AUDIT IN SUPPORT OF REVIEW OF LICENSE AMENDMENT REQUEST FOR A RISK-INFORMED APPROACH FOR ADDRESSING THE EFFECTS OF DEBRIS ON ECCS STRAINER PERFORMANCE (EPID L-2023-LLA-0092)
Dear Mr. Dietrich:
By letter dated June 13, 2023 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML23164A232), DTE Electric Company (DTE, the licensee) submitted license amendment and exemption requests for Fermi 2. The proposed amendment would revise the licensing basis described in the Fermi 2 Updated Final Safety Analysis Report to allow the use of a risk-informed method of evaluating the effects of loss-of-coolant accident (LOCA) generated debris on long-term core cooling (LTCC). The requested exemption would allow the use of risk-informed methods to evaluate the LTCC effects of debris generation resulting from a postulated LOCA in order to address the effects of debris on the operation of the emergency core cooling system strainers located in the suppression pool.
The U.S. Nuclear Regulatory Commission (NRC) staff has found 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 requires docketing to support the basis of the licensing or regulatory decision.
The NRC staff will conduct the audit virtually using a licensee-established electronic portal available to NRC staff from approximately September 18, 2023, through December 29, 2023, with formal audit meetings to be scheduled during this period as needed. The detailed audit plan is enclosed with this letter.
If you have any questions, please contact me at (301) 415-1421 or by e-mail at Surinder.Arora@nrc.gov.
Sincerely,
/RA/
Surinder Arora, Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-341
Enclosure:
Audit Plan cc: Listserv
Enclosure REGULATORY AUDIT PLAN BY THE OFFICE OF NUCLEAR REACTOR REGULATION TO SUPPORT THE REVIEW OF THE LICENSE AMENDMENT REQUEST REGARDING RISK-INFORMED APPROACH FOR EVALUATION OF DEBRIS EFFECTS ON ECCS STRAINERS DTE ENERGY COMPANY FERMI 2 POWER PLANT DOCKET NO. 50-341
1.0 BACKGROUND
By letter dated June 13, 2023 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML23164A232), DTE Electric Company (DTE, the licensee) submitted license amendment and exemption requests for Enrico Fermi 2 (Fermi 2). The proposed amendment would revise the licensing basis described in the Fermi Updated Final Safety Analysis Report to include a risk-informed method of evaluating the effects of loss-of-coolant accident (LOCA) generated debris on long-term core cooling (LTCC). The requested exemption would allow the use of risk-informed methods to evaluate the LTCC effects of debris generation resulting from a postulated LOCA in order to address the effects of debris on the operation of the emergency core cooling system strainers located in the suppression pool.
The staff from the U.S. Nuclear Regulatory Commissions (NRC) Office of Nuclear Reactor Regulation (NRR) has initiated its review of the license amendment request (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 1, dated October 2019 (ML19226A274), with exceptions noted within this audit plan.
The NRC staff performs 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 audit will assist the NRC staff with understanding the licensees approach described in the application, as supplemented, including use of industry and NRC staff guidance applicable to the resolution of boiling-water reactor strainer issues.
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 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 staffs evaluation of the technical acceptability of the probabilistic risk assessment 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).
4.0 INFORMATION AND OTHER MATERIAL NECESSARY FOR THE AUDIT The NRC staff requests information and audit meeting(s) throughout the audit period. The NRC staff uses an audit items list to identify the information (e.g., methodology, process information, and calculations) to be audited. The NRC staff provides the final audit items list as an enclosure to 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 provides 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 is not 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 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 and contractors.
Surinder Arora, Plant Licensing Branch III (LPL3)
Andrea Russell, Technical Specifications Branch (STSB)
Steve Smith, STSB Jay Robinson, PRA Licensing Branch B (APLB)
Daniel Ju, APLB Shaohua Lai, Structural, Civil, Geotech Engineering Branch (ESEB)
John Tsao, Vessels and Internals Branch (NVIB)
Matthew Yoder, Corrosion and Steam Generator Branch (NCSG)
Paul Klein, NCSG Benjamin Parks, Nuclear Methods and Fuel Analysis (SFNB)
Osvaldo Pensado, Southwest Research Institute (SwRI)
Stuart Stothoff, SwRI John Bickel, SwRI The NRC staff may request access for additional staff as the audit progresses.
6.0 LOGISTICS To support the review schedule communicated to the licensee when the NRC staff accepted the LAR for technical review, audit activities can be performed remotely and virtually using Microsoft Teams, teleconference, and a Web-based portal or other virtual meeting space created by the licensee. NRC information requests and communications with licensee staff are coordinated through the NRCs licensing project manager.
An audit will take place between September 18, 2023, through December 29, 2023. The NRCs licensing project manager will inform the licensee of the entrance and exit meeting dates when they are established. The NRC intends to set up audit meeting(s) throughout the audit period 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 when deemed necessary. An audit meeting agenda and the list of questions will be sent in advance of such audit meetings so that the licensee can have the appropriate staff to answer the staffs questions.
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 2 weeks of the date of this audit plan. The NRC staff requests that any supplemental information requested by the staff be available and accessible for the NRC staffs review as soon as practical but no later than a week from the request date. 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 NRC licensing project manager when an audit item is added to its portal by sending an e-mail.
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 licensees 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 taking part in the audit.
The online portal will prevent the NRC participants from printing, saving, downloading, or collecting any information directly from the online portal.
It is important that the files on the portal are searchable for key words.
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 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, via NRR Office Instruction LIC-115 and issue such RAIs separately from audit-related correspondence. The NRC staff will issue an audit summary report within 60 days of completing its audit.
Attachment Appendix Initial Audit Items List Item #
Audit Item 1
Files to verify the computer-aided design (CAD) model debris generation and CASA Grande software results. Specifically, the NRC staff requests:
Excel files with the debris types (generated and transported to the strainer) for every weld, break size, and break orientation (CASA Grande Results). Include the weld identifier and weld coordinates. These files must be downloadable so that NRC can manipulate the data to verify the results. This information may be provided on the docked outside of the audit.
Documentation of debris transport computations that are used to determine the conditions that result in a scenario failure due to exceeding the bed thickness criterion, including a description of assumed pump configurations and flow rates.
The document(s) that describe the different pump configurations (referred to as two-division and single-division pump states in Table 5-2 of Enclosure 3),
flow rates, and screening rationale for excluding alternative pump configurations in the risk-informed analysis.
The following references from Section 8 of the Serco calculation: 3, 10,11, 35, 36, 37, 49, 50, 51, 52, 54, 55, 56, 58, 59, 60, 63, and 91.
The following references from Appendix B of the Serco calculation: B1, B2, B3, B4, B5, B6, B7, B8, B9, and B10.
ML23248A224 OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DSS/STSB/BC NAME SArora SRohrer MJardaneh DATE 09/05/2023 09/05/2023 09/07/2023 OFFICE NRR/DNRL/NCSG/BC NRR/DRA/APLB/BC NRR/DORL/LPL3/BC NAME SBloom JWhitman JWhited DATE 09/05/2023 09/07/2023 09/07/2023 OFFICE NRR/DORL/LPL3/PM NAME SArora DATE 09/07/2023