02-31872. Draft Regulatory Guide and Associated Standard Review Plan; Issuance, Availability, Workshop

The U.S. Nuclear Regulatory Commission (NRC) has issued for public comment a draft of a regulatory guide (and its associated Standard Review Plan). Regulatory Guides are developed to describe and make available to the public such information as methods acceptable to the NRC staff for implementing specific parts of the NRC's regulations, techniques used by the staff in evaluating specific problems or postulated accidents, and data needed by the staff in its review of applications for permits and licenses.

The draft guide is temporarily identified by its task number, DG-1122, which should be mentioned in all correspondence concerning this draft guide. Draft Regulatory Guide DG-1122, “An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed Activities,” is being developed to provide guidance to licensees in determining the technical adequacy of a PRA used in a risk-informed integrated decision making process, and to endorse standards and industry guidance. Guidance is provided in four areas:

(1) A minimal set of functional requirements of a technically acceptable PRA.

(2) NRC position on consensus PRA standards and industry PRA program documents.

(3) Demonstration that the PRA (in toto or specific parts) used in regulatory applications is of sufficient technical adequacy.

(4) Documentation that the PRA (in toto or specific parts) used in regulatory applications is of sufficient technical adequacy.

DG-1122 proposes to endorse, with certain clarifications and substitutions, ASME Standard RA-S-2002, “Standard for Probabilistic Risk Assessment for Nuclear Power Plant Applications,” and Revision A3 of NEI-00-02, “Probabilistic Risk (PRA) Peer Review Process Guidance,” with its August 16, 2002 supplemental guidance on industry self-assessment.

Chapter 19.1 of the Standard Review Plan (SRP), “Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed Activities,” is being developed to provide guidance to the NRC staff on how to determine that the PRA that provides the results being used in a decision is technically adequate.

This draft guide and draft standard review plan chapter have not received complete staff approval and do not represent an official NRC staff position.

It is the NRC's intent to update this RG when a new or revised PRA standard or industry program is published. If a new standard or program is published, an additional appendix will be added to set forth the staff position. If a revision of a current standard or program would impact the staff position, the appropriate appendix would be revised.

The NRC intends to conduct a workshop on January 9, 2003, to be held in the auditorium at NRC headquarters, 11545 Rockville Pike, Rockville, Maryland, (the agenda will be announced in a future public notice), to discuss and explain the material contained in DG 1122 and SRP Chapter 19.1, and to answer questions and receive comments and feedback on the proposed documents. The purpose of the workshop is to facilitate the comment process. In the workshop, the staff will describe each document and its basis and solicit comment and feedback on their completeness, correctness, and usefulness. Since these documents cover a wide range of technical areas, many topics will be discussed. Listed below are particular topics (not limited to) on which discussion and feedback are sought at the workshop:

(1) Is the relationship of this regulatory guide to other regulatory guides (e.g., RG 1.174, RG 1.177) clear? Is it clear how this guide is to be used to support risk-informed applications? If more discussion is needed, what level of detail is needed?

(2) Is the associated SRP the appropriate place for the staff review guidance, or should the guidance be included in the application specific SRPs?

(3) Is the level of detail in the proposed guidance clear and sufficient to demonstrate the technical adequacy of the PRA to support a regulatory application? Or is more detailed guidance necessary? What level of detail is needed?

(4) Is the level of detail in the proposed guidance clear and sufficient in regard to the scope, level of detail and technical adequacy of the PRA? Or is more detailed guidance necessary? What level of detail is needed?

(5) Is the staff regulatory position on consensus PRA standards and industry PRA programs clear and sufficient? Or is more detailed guidance necessary? What level of detail is needed?

(6) Is the level of detail in the proposed guidance clear and sufficient in regard to documentation and submittal? Or is more detailed guidance necessary? What level of detail is needed?

(7) Is the staff position in the appendices of the proposed regulatory guide clear? Or is more discussion necessary? What level of detail is needed?

(8) In Appendix A, is the discussion provided on the “issue” helpful or necessary in providing the bases for the staff position? If not, should this column be removed? Is more discussion needed and what would be the appropriate level of detail?

(9) In Appendix A, the staff has provided “clarifications” to the definition regarding “dominant,” “significant,” and “important.” Clarification of these terms is provided because in places, these terms are used interchangeably (to have the same meaning) and in other places, they may be used to convey different meanings. In the context of a PRA, these terms generally are indicating that the entity under question is a major factor to the outcome under consideration. In this general sense, these terms can be used interchangeably (e.g., an important sequence, a significant sequence, a dominant sequence). However, if these terms are used to distinguish whether a requirement is imposed, a common and specific understanding (i.e., quantitative) of these terms is needed. Is this the appropriate quantitative definition? If not, what quantitative definition is appropriate?

(10) In Appendix B, the staff review of NEI-00-02 and its supplemental guidance, is based on the perspective that this document is primarily historical in that almost all the licensee's PRAs have been peer reviewed using NEI-00-02, Revision A3. Consequently, the staff endorsement does not address future use of this document. If the staff has an objection to this document, the resolution would be addressed via a licensee's self assessment. Is this approach appropriate? That is, should the staff extend its review so that industry would have the staff position regarding this process for future use?

In order to gain experience and more detailed insights into the use of the approach proposed in DG-1122 and the associated draft SRP section, during the public comment period the NRC desires to conduct a review of one or more pilot applications (e.g., Risk-Informed Technical Specifications Initiative 4b, “Configuration Risk Management for Completion Times”) using this approach. The experience and insights gained from the practical application of the approach proposed in DG-1122 and the associated draft SRP section will support the staff's risk-informed regulatory initiatives, consistent with the NRC's policy statement on PRA. The lessons learned from the pilot applications will be documented and reflected in the final regulatory guide. Since these pilot applications will assist the NRC in developing a regulatory guide, the Chief Financial Officer will waive the review fees in accordance with 10 CFR 170.11(b)(1). By granting this waiver for the pilot applications, the NRC continues its longstanding policy of granting fee exemptions for the review of license applications accepted for review as a pilot application.

The NRC staff is soliciting comments on these proposed documents. Comments may be accompanied by relevant information or supporting data. Written comments may be submitted to the Rules and Directives Branch, Office of Administration, U.S. Nuclear Regulatory Commission, Washington, DC 20555. Copies of comments received may be examined at the NRC Public Document Room, 11555 Rockville Pike, Rockville, MD. Comments will be most helpful if received by February 14, 2003.

Comments received after this 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.

You may also provide comments via the NRC's interactive rulemaking web site through the NRC home page (http://www.nrc.gov). This site provides the ability to upload comments as files (any format) if your web browser supports that function. For information about the interactive rulemaking web site, contact Ms. Carol Gallagher, [phone]; e-mail [e-mail]. For information about the draft guide and the related standard review plan chapter, contact Ms. M.T. Drouin at [phone]; e-mail [e-mail].

Although a time limit is given for comments on this draft guide, 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 this draft RG are available on the NRC's Web site <http://www.nrc.gov> in the Reference Library under Regulatory Guides. Electronic copies are also available in NRC's Public Electronic Reading Room at the same Web site; DG-1122 is under ADAMS Accession Number ML023360076. Regulatory guides are available for inspection at the NRC's Public Document Room, 11555 Rockville Pike, Rockville, MD; the PDR's mailing address is USNRC PDR, Washington, DC 20555; telephone [phone] or [phone]; fax [phone]; e-mail [e-mail]. Requests for single copies of draft or final guides (which may be reproduced) or for placement on an automatic distribution list for single copies of future draft guides in specific divisions should be made in writing to the U.S. Nuclear Regulatory Commission, Washington, DC 20555, Attention: Reproduction and Distribution Services Section; or by e-mail to [e-mail]; or by fax to [phone]. Telephone requests cannot be accommodated. Regulatory guides are not copyrighted, and Commission approval is not required to reproduce them. (5 U.S.C. 552(a))

Dated at Rockville, Maryland, this 22nd day of November, 2002.

For the Nuclear Regulatory Commission.

Scott F. Newberry,

Director, Division of Risk Analysis and Applications, Office of Nuclear Regulatory Research.