[Federal Register Volume 88, Number 236 (Monday, December 11, 2023)]
[Rules and Regulations]
[Pages 85824-85825]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-27070]


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NUCLEAR REGULATORY COMMISSION

10 CFR Parts 50, 52, and 100

[NRC-2023-0097]


Regulatory Guide: Damping Values for Seismic Design of Nuclear 
Power Plants

AGENCY: Nuclear Regulatory Commission.

ACTION: Final guide; issuance.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing 
Revision 2 to Regulatory Guide (RG), 1.61, ``Damping Values for Seismic 
Design of Nuclear Power Plants.'' This RG provides guidance on damping 
values that the NRC staff finds acceptable for use in the seismic 
response analysis of seismic Category I nuclear power plant structures, 
systems, and components. The specified damping values are intended for 
elastic dynamic seismic analysis where energy dissipation is accounted 
for by viscous damping.

DATES: Revision 2 to RG 1.61 is available on December 11, 2023.

ADDRESSES: Please refer to Docket ID NRC-2023-0097 when contacting the 
NRC about the availability of information regarding this document. You 
may obtain publicly available information related to this document 
using any of the following methods:
     Federal Rulemaking Website: Go to https://www.regulations.gov and search for Docket ID NRC-2023-0097. Address 
questions about Docket IDs in Regulations.gov to Stacy Schumann; 
telephone: 301-415-0624; email: [email protected]. For technical 
questions, contact the individuals listed in the For Further 
Information Contact section of this document.
     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 [email protected]. 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 
[email protected] 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.
    Revision 2 to RG 1.61 and the regulatory analysis may be found in 
ADAMS under Accession Nos. ML23284A272 and ML22273A041, respectively.
    Regulatory guides are not copyrighted, and NRC approval is not 
required to reproduce them.

FOR FURTHER INFORMATION CONTACT: Marcos Rolon Acevedo, Office of 
Nuclear Regulatory Research, telephone: 301-415-2208; email: 
[email protected] and Edward O'Donnell, Office of Nuclear Regulatory 
Research, telephone: 301-415-3317; email: [email protected]. Both 
are staff of the U.S. Nuclear Regulatory Commission, Washington, DC 
20555-0001.

SUPPLEMENTARY INFORMATION: 

I. Discussion

    The NRC is issuing a revision in the NRC's ``Regulatory Guide'' 
series. 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.
    Revision 2 to RG 1.61 was issued with a temporary identification of 
Draft Regulatory Guide, DG-1364. RG 1.61, Revision 1, specifies the 
damping values that the NRC staff considers acceptable for complying 
with the agency's regulations for seismic analysis. This revision of 
the RG (Revision 2) provides

[[Page 85825]]

additional guidance related to concrete properties and damping values 
for use in the development of in structure response spectra. It also 
includes guidance on damping for steel plate composite walls. In 
addition, it updates the guidance for piping damping in RG 1.61, 
Revision 1.

II. Additional Information

    The NRC published a notice of the availability of DG-1364 in the 
Federal Register on June 13, 2023 (88 FR 38408) for a 30-day public 
comment period. The public comment period closed on July 13, 2023. 
Public comments on DG-1364 and the staff responses to the public 
comments are available under ADAMS under Accession No. ML23284A274.
    As noted in the Federal Register on December 9, 2022 (87 FR 75671), 
this document is being published in the ``Rules'' section of the 
Federal Register to comply with publication requirements under 1 CFR 
chapter I.

III. Congressional Review Act

    This RG is a rule as defined in the Congressional Review Act (5 
U.S.C. 801-808). However, the Office of Management and Budget has not 
found it to be a major rule as defined in the Congressional Review Act.

IV. Backfitting, Forward Fitting, and Issue Finality

    Issuance of RG 1.61 would not constitute backfitting as that term 
is defined in section 50.109 of title 10 of the Code of Federal 
Regulations (10 CFR), ``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);'' constitute forward fitting as that term is defined and 
described in MD 8.4; or affect issue finality of an approval issued 
under 10 CFR part 52, ``Licenses, Certifications, and Approvals for 
Nuclear Power Plants,'' as explained in RG 1.61, licensees would not be 
required to comply with the positions set forth in RG 1.61.

V. 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.

    Dated: December 5, 2023.

    For the Nuclear Regulatory Commission.
Stephen M. Wyman,
Acting Chief, Regulatory Guide and Programs Management Branch, Division 
of Engineering, Office of Nuclear Regulatory Research.
[FR Doc. 2023-27070 Filed 12-8-23; 8:45 am]
BILLING CODE 7590-01-P