ML25318A135
| ML25318A135 | |
| Person / Time | |
|---|---|
| Site: | Nuclear Energy Institute |
| Issue date: | 10/31/2025 |
| From: | Anderson V Nuclear Energy Institute |
| To: | Office of Administration |
| References | |
| NRC-2025-0775, 90FR42451 00002 | |
| Download: ML25318A135 (1) | |
Text
PUBLIC SUBMISSION As of: 11/14/25, 10:57 AM Received: October 31, 2025 Status: Pending_Post Tracking No. mhf-156p-22ix Comments Due: November 03, 2025 Submission Type: Web Docket: NRC-2025-0775 Level 3 Probabilistic Risk Assessment Project Documentation (Volume 5)
Comment On: NRC-2025-0775-0001 Level 3 Probabilistic Risk Assessment Project Documentation (Volume 5)
Document: NRC-2025-0775-DRAFT-0002 Comment on FR Doc # 2025-16769 Submitter Information Organization:Nuclear Energy Institute General Comment See attached file(s)
Attachments 10-31-25_NEI Comments on NRC Draft Report on the Level 3 PRA Project Docket ID NRC-2025-0775 11/14/25, 10:58 AM NRC-2025-0775-DRAFT-0002.html file:///C:/Users/BHB1/Downloads/NRC-2025-0775-DRAFT-0002.html 1/1 SUNI Review Complete Template=ADM-013 E-RIDS=ADM-03 ADD: Alan Kuritzky, Mary Neely Comment (2)
Publication Date:
9/2/2025 Citation: 90 FR 42451
Victoria K. Anderson Technical Advisor Engineering and Risk Phone: 202.739.8101 Email: vka@nei.org October 31, 2025 Office of Administration Mail Stop: TWFN A60M U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Attn: Program Management, Announcements, and Editing Staff
Subject:
Industry Comments on NRC Draft Report on the Level 3 PRA Project: Volume 5: Overview of Reactor, Low-Power and Shutdown, Level 1, 2, and 3 PRAs for Internal Events; Docket ID NRC-2025-0775 Project Number: 689 Submitted via regulations.gov
Dear Program Management,
Announcements, and Editing Staff, On September 2, 2025, the U.S. Nuclear Regulatory Commission (NRC) issued a notice in the Federal Register requesting comments on the draft report titled, Volume 5: Overview of Reactor, Low-Power and Shutdown, Level 1, 2, and 3 PRAs for Internal Events. The Nuclear Energy Institute (NEI)1 appreciates the opportunity to submit the following comments on behalf of the nuclear energy industry.
As noted in our previous comments on other volumes in the series, including our October 3, 2025 letter on Volume 8, which stated, NEI again suggests that the NRC should strongly consider sunsetting the project absent identification of clear regulatory applicability or benefit to public safety and security, the value of continuation of the Level 3 PRA Project remains unidentified. Our position remains unchanged; NEI continues to recommend that the NRC discontinue the Level 3 PRA Project unless there is a clearly defined regulatory driver or demonstrated safety benefit.
Specific to the Low Power and Shutdown (LPSD) PRA analysis presented in Volume 5, the insights presented largely reaffirm what has long been understood through existing qualitative analyses. In particular, the analysis identified that loss of offsite power and overdrain events when entering midloop 1 The Nuclear Energy Institute (NEI) is responsible for establishing unified policy on behalf of its members relating to matters affecting the nuclear energy industry, including the regulatory aspects of generic operational and technical issues. NEIs members include entities licensed to operate commercial nuclear power plants in the United States, nuclear plant designers, major architect and engineering firms, fuel cycle facilities, nuclear materials licensees, and other organizations involved in the nuclear energy industry.
Office of Administration October 31, 2025 Page 2 Nuclear Energy Institute constituted a large portion of the risk during shutdown operations. This is not a new insight, and the industry has managed shutdown operations with this knowledge in mind for decades.
Furthermore, the report highlights numerous modeling simplifications and explicit conservatisms that significantly limit the ability of the analysis to reveal useful insights. For example, only a limited number of plant operating states were fully quantified, and these were those shown by existing analyses to have the highest contributions to plant risk during shutdown operations. Omitting other operating states from the quantification means that insights associated with lower consequence events will not be revealed by the analysis. Furthermore, this decision was made because full quantification was not feasible for this study, and indicates that a fully quantified LPSD PRA that offers practical application may not be currently possible. With respect to conservatisms, Human Reliability Analysis was limited and conservative, with acknowledged conservative performance shaping factors assigned to the majority of scenarios. Finally, non-specific equipment unavailability data was used due to the lack of comprehensive outage-specific data, leading to conservatisms in all evaluated scenarios.
Collectively, these modeling choices and conservatisms limit the ability of this analysis to offer actionable insights. The use of these assumptions may be appropriate for preliminary screening, but the necessity to use them to support completion of the analysis indicates that there is insufficient infrastructure to support a regulatory requirement for development of LPSD PRAs.
We appreciate the opportunity to comment on this draft report. If you have any questions or need additional information, please contact me at vka@nei.org or 202-739-8101.
Sincerely, Victoria K. Anderson Technical Advisor, Engineering and Risk C:
Alan Kuritzky, RES Latonia Enos-Sylla, RES