ML23079A188
| ML23079A188 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 03/24/2023 |
| From: | Audrey Klett Plant Licensing Branch 1 |
| To: | Rhoades D Constellation Energy Generation |
| Sreenivas V, NRR/DORL/LPLI, 415-2597 | |
| References | |
| EPID L-2021-LLA-0042 | |
| Download: ML23079A188 (6) | |
Text
March 24, 2023 Mr. David P. Rhoades Senior Vice President Constellation Energy Generation, LLC President and Chief Nuclear Officer Constellation Nuclear 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
LIMERICK GENERATING STATION, UNITS 1 AND 2 -
SUMMARY
OF REGULATORY AUDIT IN SUPPORT OF ALTERNATE PROCESSES FOR RISK-INFORMED CATEGORIZATION AND TREATMENT OF STRUCTURES, SYSTEMS AND COMPONENTS FOR NUCLEAR POWER REACTORS (EPID L-2021-LLA-0042)
Dear Mr. Rhoades:
By letter dated March 11, 2021, as supplemented by letter dated May 5, 2021 (Agencywide Documents Access and Management System Accession Nos. ML21070A412 and ML21125A215, respectively), Exelon Generation Company, LLC (now Constellation Energy Generation, LLC, the licensee) 1 submitted a license amendment request (LAR) for Limerick Generating Station, Units 1 and 2 (Limerick).2 The licensee requested to revise the license condition in each license pertaining to the licensees approval to use Title 10 of the Code of Federal Regulations (10 CFR), Section 50.69, Risk-informed categorization and treatment of structures, systems and components [SSCs] for nuclear power reactors, to allow the use of alternate defense-in-depth, pressure boundary, and seismic categorization processes in the licensees application of 10 CFR 50.69.
The U.S. Nuclear Regulatory Commission (NRC) staff conducted a virtual audit to support its review of the LAR. The NRC staff audited various licensee documents and interviewed licensee staff and representatives. The NRC staff issued its audit plan on October 1, 2021, as supplemented by email dated October 20, 2021, January 24, 2022, and February 2, 2022 (ML21263A248, ML21295A036, ML22028A183, and ML22034A014, respectively). The NRCs audit plan, as supplemented, contains the NRC staffs audit questions.
of this audit summary lists the individuals that took part in or attended the audit. lists the documents the NRC audited.
1 On February 1, 2022, Exelon Generation Company, LLC was renamed Constellation Energy Generation, LLC.
2 Renewed Facility Operating License Nos. NPF 39 and NPF 85, respectively
D. Rhoades 2
The NRC staff conducted the audit using virtual meetings and an Internet-based portal provided by the licensee. Using the licensees portal, the NRC staff reviewed documents (e.g., calculations and reports) related to the LAR but not available on the Limerick dockets.
During the audit, the staff also met virtually with the licensee November 15 to 17, 2021, and February 2, 2022. The staff used these meetings to confirm its understanding of the LAR, discuss the documents in the portal, and decide whether the NRC staff identified any information that needs to be submitted on the docket to complete the NRC staffs safety evaluation.
During the audit, the staff and the licensee discussed in detail the audit questions provided in the audit plan, and the staff identified information it needed on the docket to support its review.
After the audit discussions, the NRC sent the licensee a request for additional information on May 13, 2022 (ML22136A003). The licensee responded to this request on June 30, 2022 (ML22182A400). The licensee also supplemented its LAR by letters dated December 15, 2021 (ML21349B364), and February 14, 2022 (ML22045A480).
The NRCs licensing project manager informed licensee staff by telephone on March 22, 2023, that the NRC staff had completed its audit. There were no open items resulting from the audit.
If you have any questions, please contact me at (301) 415-0489 or by email to Audrey.Klett@nrc.gov.
Sincerely,
/RA/
Audrey L. Klett, Senior Project Manager Plant Licensing Branch I Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-352 and 50-353
Enclosures:
- 1. List of Audit Participants
- 2. List of Audited Documents cc: Listserv
List of Audit Participants U.S. Nuclear Regulatory Commission Licensee1 Staff Biro, Mihaela (NRR2/DRA3/APLA4)
Ballert, Zachary Brown, Adrienne (NRR/DRA/APLA)
DeAngelis, Dana Circle, Jeff (NRR/DRA/APLA)
Helker, David Curran, Gordon (NRR/DSS5/SCPB6)
Lindeman, Kurt Danna, James (NRR/DORL7/LPL18)
Linthicum, Roy Grenier, Bernard (NRR/DRA/APLB9; retired)
Loyd, Suzanne Hilsmeier, Todd (NRR/DRA/APLA)
Stewart, Glenn Ju, Daniel (OCHCO10/ADHRTD11/NRANB12)
Stone, Jeffrey Klett, Audrey (NRR/DORL/LPL1)
Tarpinian, Philip Pascarelli, Robert (NRR/DRA/APLA)
Thoryk, Jeremy Pulvirenti, April (NRR/DRA/APLA)
Rosenberg, Stacey (NRR/DRA/APLC13)
EPRI (Licensee Contractor)
Sreenivas, V (NRR/DORL/LPL1)
Chapman, Jim Tetter, Keith (NRR/DRA/APLC)
ORegan, Patrick Vasavada, Shilp (NRR/DRA/APLC)
Richards, John Wu, De (NRR/DRA/APLC)
Jensen Hughes (Licensee Contractor)
NRC Contract Staff Andersen, Vince Short, Steve M (PNNL14)
Andriano, Adam Wilk, Mark (PNNL)
Albinson, Brian Bidwell, David Holtz, Arthur Lee, Larry Nolan, Brian Passehl, David Shanley, Leo Sternowski, Nicholas Young, Charles Westinghouse (Licensee Contractor)
Rolland III, Richard W 1 Exelon Generation Company, LLC; Constellation Energy Generation, LLC 2 Office of Nuclear Reactor Regulation 3 Division of Risk Assessment 4 PRA Licensing Branch A 5 Division of Safety Systems 6 Containment and Plant Systems Branch 7 Division of Operating Reactor Licensing 8 Plant Licensing Branch 1 9 Probabilistic Risk Assessment (PRA) Licensing Branch B 10 Office of the Chief Human Capital Officer 11 Associate Director for Human Resources Training and Development 12 Nuclear Regulatory Apprenticeship Network Branch 13 PRA Licensing Branch C 14 Pacific Northwest National Laboratory (Contractor)
List of Audited Documents The U.S. Nuclear Regulatory Commission (NRC) staff audited, in a sampling manner, the following licensee documents during its review of the license amendment request for the Limerick Generating Station, Units 1 and 2 (Limerick). The NRC staff also reviewed the licensees responses to NRCs audit questions that the licensee posted on its internet-based portal.
Alternate Defense-in-Depth Walkthrough Example Alternate Pressure Boundary (Passive) Walkthrough Example Electric Power Research Institute Enhanced Method for Pressure Boundary for Limerick Audit 2021 ER-AA-569, Revision 4, Exelon 10 CFR 50.69 [Title 10 of the Code of Federal Regulations, Section 50.69] Program ER-AA-569-1001, Revision 4, 10 CFR 50.69 Active Component Risk Significance Insights ER-AA-569-1002, Revision 3, 10 CFR 50.69 Passive Component Categorization ER-AA-569-1003, Revision 6, 10 CFR 50.69 Risk Informed Categorization for Structures, Systems, and Components Letter from G.A. Hunger, Jr., Philadelphia Electric Company, to U.S. Nuclear Regulatory Commission, Limerick Generating Station, Units 1 and 2 Response to Request for Additional Information Regarding Consideration of Severe Accident Mitigation Design Alternatives, dated June 23, 1989 LG-5069-001-003, Revision 1, Main Steam System (001)
LG-5069-012-003, Revision 1, Residual Heat Removal Service Water System (012)
LG-5069-020-081-092-003, Revision 2, Diesel Generator System (020, 081, 092)
LG-5069-025-003, Revision 0, Steam Leak Detection System (025)
LG-5069-026-003, Revision 2, Process Radiation Monitoring System (026)
LG-5069-051-003, Revision 3, Residual Heat Removal System (051)
LG-5069-052-003, Revision 3, Core Spray System (052)
LG-5069-059-003, Revision 2, Primary Containment Instrument Gas System (059)
LG-5069-076-003, Revision 2, Reactor Enclosure HVAC [Heating, Ventilation, and Air Conditioning] (076)
LG-5069-078-090-003 (CR), Revision 2, CNTRL ENCL HVAC AND CHILLED WTR SYS [Control Enclosure HVAC and Chilled Water System] (78 and 90)
LG-LAR-027, Revision 2, Alternate Passive Categorization LG-LAR-028, Revision 3, Alternate Defense-in-Depth Categorization LG-PRA-007 excerpt on Level 1 PRA deterministic calculations notebook LG-PRA-012, Revision 3 excerpt on Limerick Generating Station internal flood LG-PRA-013 excerpt on summary notebook LG-PRA-014 excerpt on quantification notebook LG-PRA-021.07.02, Revision 1 excerpt on FMT LG-PRA-021.11, Revision 1 excerpt on summary and quantification LGS [Limerick Generating Station] SARA [Severe Accident Risk Assessment],
Volume 1, Section 3, Analysis of Accident Sequences Resulting from Seismic Events Limerick 50.69 Alternate Categorization License Amendment Request Audit Documentation Support Item 3, Revision 0 NUS-5203, LGS 1989 SARA Update (excerpts)
Pressurized Water Reactors Owners Group Slides for Limerick Audit 2021, dated November 15, 2021
2 RS-14-184, Limerick Unit 1 Supplemental Seismic Walkdown Report, dated November 12, 2014, RS-15-038, Limerick Unit 2 Supplemental Seismic Walkdown Report, dated March 31, 2015 Question 1 Alternative Seismic Approach Question-02 LGS 50-69 Response_Seis Rel Risk Contrib Question 3 Use of Different Approaches for Seismic Risk
D. Rhoades 3
SUBJECT:
LIMERICK GENERATING STATION, UNITS 1 AND 2 -
SUMMARY
OF REGULATORY AUDIT IN SUPPORT OF ALTERNATE PROCESSES FOR RISK-INFORMED CATEGORIZATION AND TREATMENT OF STRUCTURES, SYSTEMS AND COMPONENTS FOR NUCLEAR POWER REACTORS (EPID L-2021-LLA-0042) DATED MARCH 24, 2023 DISTRIBUTION:
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BWittick DATE 03/20/2023 03/21/2023 08/18/2022 OFFICE NRR/DRA/APLC/BC NRR/DRA/APLA/BC NRR/DORL/LPL1/BC NAME SVasavada RPascarelli HGonzalez DATE 03/21/2023 03/21/2023 03/23/2023 OFFICE NRR/DORL/LPL1/PM NAME AKlett DATE 03/24/2023 OFFICIAL RECORD COPY