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Seismic Design Classification for Nuclear Power Plants

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Nuclear Regulatory Commission.


Regulatory guide; issuance.


The U.S. Nuclear Regulatory Commission (NRC) is issuing Revision 5 of Regulatory Guide (RG) 1.29, “Seismic Design Classification for Nuclear Power Plants.” This RG describes a method that the staff of the NRC considers acceptable for use in identifying and classifying those features of light-water-reactor (LWR) nuclear power plants that must be designed to withstand the Start Printed Page 46118effects of the safe-shutdown earthquake (SSE).


Please refer to Docket ID NRC-2015-0220 when contacting the NRC about the availability of information regarding this document. You may obtain publically-available information related to this document, using the following methods:

  • Federal Rulemaking Web site: Go to and search for Docket ID NRC-2015-0220. Address questions about NRC dockets to Carol Gallagher; telephone: 301-415-3463; email: 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 Document collection at​reading-rm/​adams.html. To begin the search, select “ADAMS Public Documents” and then 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, 301-415-4737, or by email to 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. Revision 5 of RG 1.29, is available in ADAMS under Accession No. ML16118A148. The regulatory analysis is also available in ADAMS under Accession No. ML15131A397.
  • NRC's PDR: You may examine and purchase copies of public documents at the NRC's PDR, Room O1-F21, One White Flint North, 11555 Rockville Pike, Rockville, Maryland 20852.

Regulatory guides are not copyrighted, and NRC approval is not required to reproduce them.

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Yiu Law, Office of New Reactors, telephone: 301-415-0523, email:, and Edward O'Donnell, Office of Nuclear Regulatory Research, telephone: 301-415-3317, email: Edward.O' Both are staff members of the U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.

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I. Introduction

The NRC is issuing a revision to an existing guide in the NRC's “Regulatory Guide” series. This series was developed to describe and make available to the public information regarding methods that are acceptable to the NRC staff for implementing specific parts of the agency's regulations, techniques that the staff uses in evaluating specific issues or postulated events, and data that the staff needs in its review of applications for permits and licenses.

Revision 5 of RG 1.29 was issued with a temporary identification of Draft Regulatory Guide, DG-1315. Revision 5 of RG 1.29 contains minor non-substantive changes that do not present new regulatory requirements, but clarifies content in Section C, “Staff Regulatory Guidance,” by (1) addition of a reference to the definition of the reactor coolant pressure boundary in section 50.2 of title 10 of the Code of Federal Regulations (10 CFR), and (2) a reorganization of systems and subsystems to add clarity to the staff guidance. In addition, it adds a reference to a related international standard, and it was reformatted to align with the current program guidance for regulatory guides.

II. Additional Information

The DG-1315 was published in the Federal Register (80 FR 55878) on September 17, 2015 for a 60-day public comment period. Public comments on DG-1315 and the staff's responses to the public comments are available in ADAMS under Accession No. ML16118A149.

III. Backfitting and Issue Finality

The RG 1.29 describes a method that the staff of the NRC considers acceptable for use in identifying and classifying those features of LWR nuclear power plants that must be designed to withstand the effects of the SSE. Issuance of this RG does not constitute backfitting as defined in 10 CFR 50.109 (the Backfit Rule) and is not otherwise inconsistent with the issue finality provisions in 10 CFR part 52. As discussed in the “Implementation” section of this RG, the NRC has no current intention to impose this RG on holders of current operating licenses or combined licenses.

This RG may be applied to applications for operating licenses, combined licenses, early site permits, and certified design rules docketed by the NRC as of the date of issuance of the final regulatory guide, as well as future applications submitted after the issuance of the regulatory guide. Such action would not constitute backfitting as defined in the Backfit Rule or be otherwise inconsistent with the applicable issue finality provision in 10 CFR part 52, inasmuch as such applicants or potential applicants are not within the scope of entities protected by the Backfit Rule or the relevant issue finality provisions in part 52.

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Dated at Rockville, Maryland, this 8th day of July 2016.

For the Nuclear Regulatory Commission.

Carol E. Moyer,

Acting Chief, Regulatory Guidance and Generic Issues Branch, Division of Engineering, Office of Nuclear Regulatory Research.

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[FR Doc. 2016-16767 Filed 7-14-16; 8:45 am]