2017-02864. Comprehensive Vibration Assessment Program for Reactor Internals During Preoperational and Startup Testing

AGENCY:

Nuclear Regulatory Commission.

ACTION:

Regulatory guide; issuance.

SUMMARY:

The U.S. Nuclear Regulatory Commission (NRC) is issuing Revision 4 to Regulatory Guide (RG) 1.20, “Comprehensive Vibration Assessment Program for Reactor Internals During Preoperational and Startup Testing.” This RG describes methods and procedures that the NRC staff considers acceptable when developing a comprehensive vibration assessment program for reactor internals during preoperational and startup testing.

DATES:

Revision 4 to RG 1.20 is available on February 13, 2017.

ADDRESSES:

Please refer to Docket ID NRC-2015-0161 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 http://www.regulations.gov and search for Docket ID NRC-2015-0161. Address questions about NRC dockets to Carol Gallagher; telephone: [phone]; email: [e-mail]. 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 http://www.nrc.gov/​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 [e-mail]. 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 4 to Regulatory Guide 1.20, and the regulatory analysis may be found in ADAMS under Accession Nos. ML16056A338 and ML15083A388, respectively.
• 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.

FOR FURTHER INFORMATION CONTACT:

Thomas Scarbrough, Office of New Reactors, telephone: [phone], email: [e-mail]; Yuken Wong, Office of New Reactors, telephone: [phone], email: [e-mail], and Stephen Burton, Office of Nuclear Regulatory Research, telephone: [phone], email: [e-mail]. All are staff members of the U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.

SUPPLEMENTARY INFORMATION:

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 NRC staff uses in evaluating specific issues or postulated events, and data that the NRC staff needs in its review of applications for permits and licenses.

Revision 4 of RG 1.20 was issued with a temporary identification of Draft Regulatory Guide, DG-1323. This revision expands the guidance related to flow-induced vibration, acoustic resonance, acoustic-induced vibration, and mechanical-induced vibration for boiling water reactor, pressurized water reactor, and small modular reactor (SMR) nuclear power plants. For SMRs, this includes guidance for the control rod drive system and control rod drive mechanisms, which might be contained in an integral reactor vessel module. The additional guidance in Revision 4 is based in part on lessons learned from the review of recent applications, including both new plant applications and extended power uprate applications. In addition, Revision 4 re-defines and clarifies the prototype, limited prototype, and non-prototype classifications of reactor internal configurations.

II. Additional Information

The DG-1323 was published in the Federal Register on July 2, 2015 (80 FR 38239) for a 60-day public comment period. The public comment period closed on August 31, 2015. Public comments on DG-1323 and the NRC staff responses to the public comments are available in ADAMS under Accession No. ML16056A341.

III. Congressional Review Act

This regulatory guide 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 and Issue Finality

Issuance of this regulatory guide does not constitute backfitting as defined in section 50.109 of title 10 of the Code of Federal Regulation s (10 CFR) (the Backfit Rule), and is not otherwise inconsistent with the issue finality provisions in 10 CFR part 52. This regulatory guide does not apply to any nuclear reactor construction permits or operating licenses under 10 CFR part 50, design certifications and combined licenses under 10 CFR part 52, or license amendment requests for extended power uprates at operating reactors already issued by the NRC prior to issuance of the regulatory guide. The NRC has already completed its review of the comprehensive vibration assessment programs (CVAPs) for power reactor internals for these construction permits, operating licenses, design certifications, combined operating licenses, and license amendments for extended power uprates. Therefore, no further NRC regulatory action with respect to CVAPs will occur for those licenses, permits, certifications, and authorizations for which the guidance in the regulatory guide is relevant, absent voluntary action by the licensees to use the guidance to demonstrate compliance with the underlying NRC regulations. The regulatory guide may be applied to applications for construction permits, operating licenses, design certifications, combined licenses, and license amendments for extended power uprates, any of which are docketed and under review by the NRC as of the date of issuance of the regulatory guide. The regulatory guide may also be applied to applications for construction permits, operating licenses, design certifications, combined licenses, and license amendments for extended power uprates, any of which are submitted after the issuance of the regulatory guide. Such action would not constitute backfitting as defined in 10 CFR 50.109(a)(1) and is not otherwise inconsistent with the applicable issue finality provisions in 10 CFR part 52 because such applicants and potential applicants are not, with certain exceptions, protected by either the Backfit Rule or any issue finality provisions under 10 CFR part 52. This is because neither the Backfit Rule nor the issue finality provisions under 10 CFR part 52—with certain exclusions discussed below—was intended to apply to every NRC action that substantially changes the expectations of current and future applicants. The exceptions to the general principle are applicable whenever an applicant references a 10 CFR part 52 license (e.g., an early site permit), NRC regulatory approval (e.g., a design certification rule), or both, with specified issue finality provisions. The NRC does not, at this time, intend to impose the positions represented in the regulatory guide in a manner that is inconsistent with any issue finality provisions. If, in the future, the staff seeks to impose a position in the regulatory guide in a manner that does not provide issue finality as described in the applicable issue finality provision, then the staff must address the criteria for avoiding issue finality as described in the applicable issue finality provision.

Dated at Rockville, Maryland, this 8th day of February, 2017.

For the Nuclear Regulatory Commission.

Thomas H. Boyce,

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