ML21075A008

Comment (2) of Frances A. Pimentel on Behalf of Nuclear Energy Institute to Considerations for Estimating Site-Specific Probable Maximum Precipitation at Nuclear Power Plants in the United States of America

ML21075A008
Person / Time
Site:	Nuclear Energy Institute
Issue date:	03/01/2021
From:	Pimentel F Nuclear Energy Institute
To:	Office of Administration
References
86FR85683 00002, NRC-2020-0237
Download: ML21075A008 (5)

Text

3/16/2021 blob:https://www.fdms.gov/f6ab1abb-9d5c-4407-a8cf-7865142c88f8 SUNI Review Complete Template=ADM-013 As of: 3/16/21 7:39 AM E-RIDS=ADM-03 Received: March 01, 2021 PUBLIC SUBMISSION ADD: Kevin Quilan, Luissette Candelario, Status: Pending_Post Tracking No. klq-z0e6-mprm Mike Lee, Mary Neely Comment (2)

Comments Due: March 01, 2021 Publication Date: Submission Type: Web 12/29/2020 Citation: 86 FR 85683 Docket: NRC-2020-0237 Considerations for Estimating Site-Specific Probable Maximum Precipitation at Nu-clear Power Plants in the United States of America Comment On: NRC-2020-0237-0001 Considerations for Estimating Site-Specific Probable Maximum Precipitation at Nuclear Power Plants in the United States of America Document: NRC-2020-0237-DRAFT-0003 Comment on FR Doc # 2020-28708 Submitter Information Email: fap@nei.org Organization: Nuclear Energy Institute General Comment NEI Comments on Draft NUREG/KM- 0015, Considerations for Estimating Site-Specific Probable Maximum Precipitation at Nuclear Power Plants in the United States of America, 85 FRN 85683-85685; Docket ID NRC-2020-0237 Attachments 03-01-21_Letter to NRC with Industry Comments on Draft NUREG KM-0015 with Attachment blob:https://www.fdms.gov/f6ab1abb-9d5c-4407-a8cf-7865142c88f8 1/1

FRANCES PIMENTEL Senior Project Manager, Risk and Technical Support 1201 F Street, NW, Suite 1100 Washington, DC 20004 NUCLEAR ENERGY INSTITUTE P: 202.739.8132 fap@nei.org nei.org March 1, 2021 Office of Administration Mail Stop: TWFN-7-A60M U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 ATTN: Program Management, Announcements and Editing Staff Project Number: 689

Subject:

NEI Comments on Draft NUREG/KM- 0015, Considerations for Estimating Site-Specific Probable Maximum Precipitation at Nuclear Power Plants in the United States of America, 85 FRN 85683-85685; Docket ID NRC-2020-0237.

Subm itted via regulations.gov

Dear Program Management,

Announcements and Editing Staff, The Nuclear Energy Institute (NEI) 1, on behalf of our members, appreciates the opportunity to provide comments on the subject Draft NUREG/KM- 0015, Considerations for Estimating Site-Specific Probable Maximum Precipitation at Nuclear Power Plants in the United States of America. We are supportive of the staffs efforts to maintain and preserve knowledge concerning the lessons-learned from the recent flood hazard re-evaluations at current and planned nuclear power plant sites performed most recently in connection with the staff 2012 §50.54(f) reviews in the creation of this document.

In our review, we noted that this draft NUREG/KM summarizes the knowledge the NRC staff has developed over the course of the reviews based on the similarities and differences between methodologies pertaining to site-specific probable maximum precipitation (SSPMP) calculated at U.S. nuclear power plants. The attachment includes several recommendations to enhance the document and improve clarity for your use in finalizing this regulatory guide.

We appreciate the NRCs effort in developing this draft guidance and encourage your consideration of all stakeholder comments prior to finalizing this draft NUREG. We trust that you will find these comments useful 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.

NUCLEAR. CLEAN AIR ENERGY

Program Management, Announcements and Editing Staff March 1, 2021 Page 2 and informative. Please contact me at fap@nei.org or (202) 739-8132 with any questions or comments about the content of this letter or the attached comments.

Sincerely, Frances A. Pimentel Attachment c: Kevin Quinlan, NRR/DEX/EXHB

Attachment 1 Comments on Draft NUREG/KM- 0015, Considerations for Estimating Site-Specific Probable Maximum Precipitation at Nuclear Power Plants in the United States of America.

Section Comment/Basis Recommendation TOC / Overall The document provides guidance on how to use existing Add a section on Gathering New Information.

information to estimate Site-Specific Probable Maximum Precipitation at NPPs in the US. In many places, it talks about

1. professional judgement, justification and documentation.

It would be useful to have a section on Gathering New Information to fill in gaps.

TOC / Overall The document is basically a Knowledge Summary of work that Add a section on Gathering New Information.

2. has been performed in the US. It would be useful to have a section if similar work has been performed in Europe.

TOC / Overall It would be useful to have a section on the most common gaps Add a section on the most common gaps seen in the 50.54(f)

3. seen in the 50.54(f) submittals. What were the most common submittals and the most common NRC Request for Additional NRC Requests for Additional Information? Information.

Section 1.1 This sections states, GDC 2 requires, []. GDC 2 also requires Change GDC 2 requires to GDC 2 states that in the two Background [.]. sentences as described in comment/basis.

4. Since GDC can only be described as requirements for post-GDC plants and under particular circumstances (see COM-SECY 0020) change this wording to be, GDC 2 states that.

Section Recommend that the NUREG provide discussion on the Provide discussion as described in comment/basis.

1.6/2.2 benefits/reasons of developing and utilizing site-specific PMP 5.

analyses in lieu of generalized event derivations from sources such as Hydrometeorological Reports (HMRs).

Section Comment/Basis Recommendation Section 9.1.1 additional wording Insert new paragraph:

In a submitted LAR, artificial isohyetal storm patterns, as discussed in HMR No. 52, were not used. PMP values from an NRC-approved TP, adjusted to account for topographic influences, was generated for each grid point on a gridded network covering the entire drainage basin for given storm areas and durations. The gridded

6. PMP approach produces a default spatial pattern that closely follows NOAA Atlas 14 precipitation frequency patterns following the approach in HMRs 55A, 57 and 59. Since the total drainage basin consisted of numerous sub-basins and dams, a large number of spatial distributions over sub-basins and combinations of sub-basins were evaluated in the hydraulic modeling to maximize volume over various portions of the watershed to test for dam failures and to maximize stream-flow and flooding levels at plant sites.

Section 9.2 Recommend providing examples of any concerns/challenges that Provide examples as described in comment/basis.

were encountered during review of licensee site-specific PMP

7. estimates. Specifically, any analytical techniques or inputs that resulted in licensees revising and resubmitting site-specific PMP calculations.

Section 9.2 Additional wording After the words, historical rainfall events or different isohyetal

8. patterns recommend adding the words or gridded sub-basin combinations 11.1 Recommend including a discussion on how site-specific PMP Provide discussion as described in comment/basis.

Paragraph 2 estimates relate to the current licensee guidance documents.

The currently approved revision of Regulatory Guide 1.59

9. significantly pre-dates many of the scientific advancements, research and source documents that have made site-specific estimations a viable meteorological option.