Draft Regulatory Guides: Design-Basis Floods for Nuclear Power Plants and Guidance for Assessment of Flooding Hazards Due to Water Control Structure Failures and Incidents

AGENCY:

Nuclear Regulatory Commission.

ACTION:

Draft guides; request for comment.

SUMMARY:

The U.S. Nuclear Regulatory Commission (NRC) is issuing for public comment two related draft Regulatory Guides (DG) namely DG-1290, Revision 1, “Design-Basis Floods for Nuclear Power Plants,” proposed Revision 3 of Regulatory Guide (RG) 1.59 of the same name and DG-1417, “Guidance for Assessment of Flooding Hazards due to Water Control Structure Failures and Incidents,” proposed new RG 1.256. DG-1290 provides guidance for applicants for new nuclear power plants (NPPs) on acceptable methods for evaluating design-basis floods and DG-1417 provides guidance for applicants on flooding hazards due to failure or other incidents at man-made water control structures including, but not limited to, dams and levees.

DATES:

Submit comments by August 14, 2024. Comments received after this date will be considered if it is practical to do so, but the NRC is able to ensure consideration only for comments received on or before this date.

ADDRESSES:

You may submit comments by any of the following methods; however, the NRC encourages electronic comment submission through the Federal rulemaking website:

• Federal rulemaking website: Go to https://www.regulations.gov and search for Docket ID NRC-2024-0110. Address questions about Docket IDs in Regulations.gov to Stacy Schumann; telephone: 301-415-0624; email: Stacy.Schumann@nrc.gov. For technical questions, contact the individuals listed in the FOR FURTHER INFORMATION CONTACT section of this document.
• Mail comments to: Office of Administration, Mail Stop: TWFN-7-A60M, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, ATTN: Program Management, Announcements and Editing Staff.

For additional direction on obtaining information and submitting comments, see “Obtaining Information and Submitting Comments” in the SUPPLEMENTARY INFORMATION section of this document.

FOR FURTHER INFORMATION CONTACT:

Edward O'Donnell, Office of Nuclear Regulatory Research, telephone: 301-415-3317; email: Edward.O'Donnell@nrc.gov; Joseph Kanney, Office of Nuclear Regulatory Research, telephone: 301-415-1920; email: Joseph.Kanney@nrc.gov; and Kenneth See, Office of Nuclear Reactor Regulation, telephone: 301-415-1508; email: Kenneth.See@nrc.gov. All are staff of the U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.

SUPPLEMENTARY INFORMATION:

I. Obtaining Information and Submitting Comments

A. Obtaining Information

Please refer to Docket ID NRC-2024-0110 when contacting the NRC about the availability of information for this action. You may obtain publicly available information related to this action by any of the following methods:

• Federal Rulemaking Website: Go to https://www.regulations.gov and search for Docket ID NRC-2024-0110.
• NRC's Agencywide Documents Access and Management System (ADAMS): You may obtain publicly available documents online in the ADAMS Public Documents collection at https://www.nrc.gov/reading-rm/adams.html. To begin the search, select “Begin Web-based ADAMS Search.” For problems with ADAMS, please contact the NRC's Public Document Room (PDR) reference staff at 1-800-397-4209, at 301-415-4737, or by email to PDR.Resource@nrc.gov. The ADAMS accession number for each document referenced (if it is available in ADAMS) is provided the first time that it is mentioned in this document.
• NRC's PDR: The PDR, where you may examine and order copies of publicly available documents, is open by appointment. To make an appointment to visit the PDR, please send an email to PDR.Resource@nrc.gov or call 1-800-397-4209 or 301-415-4737, between 8 a.m. and 4 p.m. eastern time (ET), Monday through Friday, except Federal holidays.

B. Submitting Comments

The NRC encourages electronic comment submission through the Federal rulemaking website ( https://www.regulations.gov ). Please include Docket ID NRC-2024-0110 in your comment submission.

The NRC cautions you not to include identifying or contact information that you do not want to be publicly disclosed in your comment submission. The NRC will post all comment submissions at https://www.regulations.gov as well as enter the comment submissions into ADAMS. The NRC does not routinely edit comment submissions to remove identifying or contact information.

If you are requesting or aggregating comments from other persons for submission to the NRC, then you should inform those persons not to include identifying or contact information that they do not want to be publicly disclosed in their comment submission. Your request should state that the NRC does not routinely edit comment submissions to remove such information before making the comment submissions available to the public or entering the comment into ADAMS.

II. Additional Information

The NRC is issuing for public comment two related DGs in the NRC's “Regulatory Guide” series, namely DG-1290 and DG-1417. This series was developed to describe methods that are acceptable to the NRC staff for implementing specific parts of the agency's regulations, to explain techniques that the staff uses in evaluating specific issues or postulated events, and to describe information that the staff needs in its review of applications for permits and licenses.

DG-1290 was previously released for public comment on February 23, 2022, as announced in the Federal Register (87 FR 10260). The public comment period ended on April 11, 2022. That version of DG-1290 can be found in ADAMS under Accession No. ML19289E561 and the response to public comments can be found at ADAMS Accession No. ML23320A026. DG-1290, Revision 1 (ADAMS Accession No. ML23320A025) is being issued for a second round of comments due to changes reflecting public comments and proposed referencing of a complementary new guide, DG-1417 (RG 1.256, Revision 0) “Guidance for Assessment of Flooding Hazards Due to Water Control Structure Failures and Incidents.” DG-1417 will be released for comment in conjunction with DG-1290, Revision 1.

DG-1417 is a proposed new RG, RG 1.256, of the same name, and is temporarily identified by its task number, DG-1417 (ADAMS Accession No. ML22278A110). It was developed to provide guidance to applicants for new NPPs on acceptable methods for evaluating design-basis flooding hazards due to failure or other incidents at man-made water control structures including, but not limited to, dams and levees. If finalized, RG 1.256 would formally incorporate interim staff guidance (ISG) “Guidance for Assessment of Flooding Hazards Due to Dam Failure” (JLD-ISG-2013-01) (ADAMS Accession No. ML13151A153) into NRC's regulatory guidance framework. ISGs are meant to be withdrawn after their immediate purpose has been fulfilled or integrated formally into the NRC's regulatory guidance framework. If DG-1417 is finalized as RG 1.256, JLD-ISG-2013-01 will be withdrawn. The staff is also issuing for public comment a draft regulatory analysis for DG-1417 (ADAMS Accession No. ML22278A111). The staff developed the regulatory analysis to assess the value of issuing or revising a RG, as well as alternative courses of action. A regulatory analysis for DG-1290 was released for comment on February 23, 2022, and although no comments were received it is available for comment and can be found in ADAMS under Accession No. ML12121A020.

As noted in the Federal Register on December 9, 2022 (87 FR 75671), this document is being published in the “Proposed Rules” section of the Federal Register to comply with publication requirements under chapter I of title 1 of the Code of Federal Regulations (CFR).

III. Backfitting, Forward Fitting, and Issue Finality

If finalized, the NRC staff may use RG 1.256 as a reference in its regulatory processes, such as licensing, inspection, or enforcement. However, the NRC staff does not intend to use the proposed guidance in RG 1.256 to support NRC staff actions in a manner that would constitute backfitting as that term is defined in 10 CFR 50.109, “Backfitting,” and as described in NRC Management Directive (MD) 8.4, “Management of Backfitting, Forward Fitting, Issue Finality, and Information Requests,” (ADAMS Accession No. ML18093B087); nor does the NRC staff intend to use the proposed guidance to affect the issue finality of an approval under 10 CFR part 52, “Licenses, Certifications, and Approvals for Nuclear Power Plants.” The staff also does not intend to use the proposed guidance to support NRC staff actions in a manner that constitutes forward fitting as that term is defined and described in MD 8.4. If a licensee believes that the NRC is using this proposed RG in a manner inconsistent with the discussion in this Implementation section, then the licensee may file a backfitting or forward fitting appeal with the NRC in accordance with the process in MD 8.4.

IV. Submitting Suggestions for Improvement of Regulatory Guides

A member of the public may, at any time, submit suggestions to the NRC for improvement of existing RGs or for the development of new RGs. Suggestions can be submitted on the NRC's public website at https://www.nrc.gov/reading-rm/doc-collections/reg-guides/contactus.html. Suggestions will be considered in future updates and enhancements to the “Regulatory Guide” series.