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Draft Regulatory Guide: Issuance, Availability

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Nuclear Regulatory Commission.


Notice of Issuance and Availability of Draft Regulatory Guide, DG-1226.

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Donald Helton, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, telephone: (301) 251-7594 or e-mail to

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I. Introduction

The U.S. Nuclear Regulatory Commission (NRC) is issuing for public comment a draft guide in the agency's “Regulatory Guide” series. This series was developed to describe and make available to the public such information as methods that are acceptable to the NRC staff for implementing specific parts of the NRC's regulations, techniques that the staff uses in evaluating specific problems or postulated accidents, and data that the staff needs in its review of applications for permits and licenses.

The draft regulatory guide (DG), titled, “An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis,” is temporarily identified by its task number, DG-1226, which should be mentioned in all related correspondence. DG-1226 is proposed Revision 2 of Regulatory Guide 1.174, dated November 2002. The NRC's policy statement on probabilistic risk assessment (PRA) encourages greater use of this analysis technique to improve safety decisionmaking and Start Printed Page 45885improve regulatory efficiency. A description of current risk-informed initiatives may be found in (1) recent updates to the NRC staff's Risk-Informed and Performance-Based Plan (RPP) formerly known as the Risk-Informed Regulation Implementation Plan, and (2) the agency Internet site at​about-nrc/​regulatory/​risk-informed.html.

One significant activity undertaken in response to the policy statement is the use of PRA to support decisions to modify an individual plant's licensing basis (LB). This regulatory guide provides guidance on the use of PRA findings and risk insights to support licensee requests for changes to a plant's LB, as in requests for license amendments and technical specification changes under Title 10 of the Code of Federal Regulations (10 CFR) Sections 50.90, “Application for Amendment of License, Construction Permit, or Early Site Permit,” through 50.92, “Issuance of Amendment.” It does not address licensee-initiated changes to the LB that do NOT require NRC review and approval (e.g., changes to the facility as described in the final safety analysis report (FSAR), the subject of 10 CFR 50.59, “Changes, Tests, and Experiments”).

II. Further Information

The NRC staff is soliciting comments on DG-1226. Comments may be accompanied by relevant information or supporting data and should mention DG-1226 in the subject line. Comments submitted in writing or in electronic form will be made available to the public in their entirety through the NRC's Agencywide Documents Access and Management System (ADAMS).

Because your comments will not be edited to remove any identifying or contact information, the NRC cautions you against including any information in your submission that you do not want to be publicly disclosed.

The NRC requests that any party soliciting or aggregating comments received from other persons for submission to the NRC inform those persons that the NRC will not edit their comments to remove any identifying or contact information, and therefore, they should not include any information in their comments that they do not want publicly disclosed. You may submit comments by any of the following methods:

1. Mail comments to: Rulemaking and Directives Branch, Mail Stop: TWB-05-B01M, Office of Administration, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.

2. Federal e-Rulemaking Portal: Go to and search for documents filed under Docket ID [NRC-2009-0385]. Address questions about NRC dockets to Carol Gallagher, 301-492-3668; e-mail

3. Fax comments to: Rulemaking and Directives Branch, Office of Administration, U.S. Nuclear Regulatory Commission at (301) 492-3446.

Requests for technical information about DG-1226 may be directed to the NRC contact, Donald Helton at (301) 251-7594 or e-mail to

Comments would be most helpful if received by November 3, 2009. Comments received after that 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. Although a time limit is given, comments and suggestions in connection with items for inclusion in guides currently being developed or improvements in all published guides are encouraged at any time.

Electronic copies of DG-1226 are available through the NRC's public Web site under Draft Regulatory Guides in the “Regulatory Guides” collection of the NRC's Electronic Reading Room at​reading-rm/​doc-collections/​. Electronic copies are also available in ADAMS (​reading-rm/​adams.html), under Accession No. ML091200100.

In addition, regulatory guides are available for inspection at the NRC's Public Document Room (PDR) located at 11555 Rockville Pike, Rockville, Maryland. The PDR's mailing address is USNRC PDR, Washington, DC 20555-0001. The PDR can also be reached by telephone at (301) 415-4737 or (800) 397-4205, by fax at (301) 415-3548, and by e-mail to

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

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Dated at Rockville, Maryland, this 25 day of August 2009.

For the Nuclear Regulatory Commission.

Andrea D. Valentin,

Chief, Regulatory Guide Development Branch, Division of Engineering, Office of Nuclear Regulatory Research.

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[FR Doc. E9-21470 Filed 9-3-09; 8:45 am]