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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)-1200.

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Mary Drouin, U. S. Nuclear Regulatory Commission, Washington, DC 20555-0001, telephone: (301) 415-6675 or e-mail to

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I. Introduction

The U.S. Nuclear Regulatory Commission (NRC) has issued for public comment a draft guide in the agency's Regulatory Guide Series. This series has been developed to describe and make available to the public such information Start Printed Page 35171as 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), entitled, “An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed Activities,” is temporarily identified by its task number, DG-1200, which should be mentioned in all related correspondence. DG-1200 is proposed Revision 2 of Regulatory Guide 1.200.

In 1995, the NRC issued a Policy Statement on the use of probabilistic risk analysis (PRA), encouraging its use in all regulatory matters. That Policy Statement states that “* * * the use of PRA technology should be increased to the extent supported by the state-of-the-art in PRA methods and data and in a manner that complements the NRC's deterministic approach.” Since that time, many uses have been implemented or undertaken, including modification of the NRC's reactor safety inspection program and initiation of work to modify reactor safety regulations. Consequently, confidence in the information derived from a PRA is an important issue, in that the accuracy of the technical content must be sufficient to justify the specific results and insights that are used to support the decision under consideration.

This guide describes one acceptable approach for determining whether the quality of the PRA, in total or the parts that are used to support an application, is sufficient to provide confidence in the results, such that the PRA can be used in regulatory decision-making for light-water reactors. This guidance is intended to be consistent with the NRC's PRA Policy Statement. It is also intended to reflect and endorse guidance provided by standards-setting and nuclear industry organizations.

When used in support of an application, this regulatory guide will obviate the need for an in-depth review of the base PRA by NRC reviewers, allowing them to focus their review on key assumptions and areas identified by peer reviewers as being of concern and relevant to the application. Consequently, this guide will provide for a more focused and consistent review process. In this regulatory guide, the quality of a PRA analysis used to support an application is measured in terms of its appropriateness with respect to scope, level of detail, and technical acceptability.

The NRC staff has scheduled a public meeting on July 11, 2008, (9 a.m. to 12 p.m.), at NRC headquarters (11545 Rockville Pike, Rockville, Maryland 20852, conference room T-10A1) to discuss DG-1200. The meeting will focus on the changes in DG-1200 from the previous revision of this guide (i.e., Regulatory Guide 1.200, Revision 1). Call-in capability will be made available for those individuals who can not travel to NRC headquarters; however, only a limited number of call-in lines can be made available. Please contact Mary Drouin (e-mail or 307-415-6675), if you plan to call in. The meeting will also be noticed at least 10 days prior to the meeting, which will include an agenda and the call-in number.

II. Further Information

The NRC staff is soliciting comments on DG-1200 (including any implementation schedule) and its associated regulatory analysis or value/impact statement. Comments may be accompanied by relevant information or supporting data and should mention DG-1200 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).

Personal information will not be removed from your comments. You may submit comments by any of the following methods:

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

2. E-mail comments to:

3. Hand-deliver comments to: Rulemaking, Directives, and Editing Branch, Office of Administration, U.S. Nuclear Regulatory Commission, 11555 Rockville Pike, Rockville, Maryland 20852, between 7:30 a.m. and 4:15 p.m. on Federal workdays.

4. Fax comments to: Rulemaking, Directives, and Editing Branch, Office of Administration, U.S. Nuclear Regulatory Commission at (301) 415-5144.

Requests for technical information about DG-1200 may be directed to the NRC contact, Mary Drouin at (301) 415-6675 or e-mail to

Comments would be most helpful if received by August 25, 2008. 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-1200 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. ML081200566.

In addition, regulatory guides are available for inspection at the NRC's Public Document Room (PDR), which is 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 16th day of June, 2008.

For the Nuclear Regulatory Commission.

Stephen C. O'Connor,

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

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[FR Doc. E8-13966 Filed 6-19-08; 8:45 am]