ML081610609

Withdrawal of Risk-Informed Relief Request 13R-01

ML081610609
Person / Time
Site:	Braidwood
Issue date:	06/17/2008
From:	David M NRC/NRR/ADRO/DORL/LPLIII-2
To:	Pardee C Exelon Generation Co
marshall david 415-1547
References
TAC MD8456, TAC MD8457
Download: ML081610609 (6)

Text

June 17, 2008 Mr. Charles G Pardee Chief Nuclear Officer and Senior Vice President Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

BRAIDWOOD STATION, UNITS 1 AND 2 - WITHDRAWAL OF RISK-INFORMED RELIEF REQUEST 13R-01 (TAC NOS. MD8456 AND MD8457)

Dear Mr. Pardee:

By letter dated March 31, 2008 (Agencywide Documents Access Management System (ADAMS)

Accession No. ML080910472), Exelon Generation Company, LLC submitted a relief request (RR) for Braidwood Station, Units 1 and 2 (Braidwood). In that letter, you requested authorization to use a risk-informed inservice inspection program as an alternative to the examination program of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code,Section XI, 2001 Edition through the 2003 Addenda for examination category B-F, B-J, C-F-1, and C-F-2 pressure retaining piping welds.

The Nuclear Regulatory Commission (NRC) staff performed an acceptance review of the Braidwood RR. The acceptance review was performed to determine if there is sufficient technical information in scope and depth to allow the NRC staff to complete its detailed technical review. The acceptance review was also performed to identify whether the request had any readily apparent information insufficiencies in its characterization of the regulatory requirements or the licensing basis of the plant.

As a result of the acceptance review, the NRC staff concluded that the Braidwood RR did not provide sufficient detail technical information to enable the NRC staff to complete its detailed review and make an independent assessment regarding whether the proposed alternative would provide an acceptable level of quality and safety. The NRC staff discussed the information that was insufficient in a call with your staff on May 15, 2008.

By letter dated May 29, 2008 (ADAMS Accession No. ML081500828), you requested to withdraw the RR from NRC staff review. The NRC staff acknowledges your withdrawal request. Activities on the review have ceased, and the associated Technical Assignment Control numbers have been closed.

C. G. Pardee The information that the NRC staff found to be insufficient is listed in the enclosure to this letter for your consideration in the event that you submit a risk-informed RR in the future. If you have any questions, please contact me at (301) 415-1547.

Sincerely,

/RA/

Marshall J. David, Senior Project Manager Plant Licensing Branch III-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. STN 50-456 and STN 50-457

Enclosure:

As stated cc w/encl: See next page

ML081610609 NRR-106 OFFICE LPL3-2/PM LPL3-2/LA DRA/APLA/BC LPL3-2/BC NAME MDavid EWhitt MRubin RGibbs DATE 6/11/ 08 6/11/ 08 6/12/08 6/17/08

INSUFFICIENT INFORMATION BRAIDWOOD STATION, UNITS 1 AND 2 RISK-INFORMED RELIEF REQUEST 13R-01 By letter dated March 31, 2008 (Agencywide Documents Access Management System (ADAMS)

Accession No. ML080910472), Exelon Generation Company, LLC (Exelon, the licensee) submitted request for alternative 13R-01. The request for alternative proposed a risk-informed (RI) selection and examination program as an alternative to a portion of the current inservice inspection (ISI) program for Braidwood Station, Units 1 and 2 (Braidwood), on the basis that the alternative provides an acceptable level of quality and safety. Exelon requested to implement the RI-ISI program based on the Revised Risk-Informed Inservice Inspection Evaluation Procedure (EPRI TR-112657, Revision B-A, December 1999).

The Nuclear Regulatory Commission (NRC) staff performed an acceptance review of the application and all supporting information. As a result of that review, the NRC staff concluded that the safety analysis that supports the relief request (RR) does not include the following technical information in sufficient detail to enable it to make an independent assessment regarding the acceptability of the proposal in terms of regulatory requirements and the protection of public health and safety.

NRC staff reviews of proposed RI-ISI programs are performed in accordance with Regulatory Guide (RG) 1.178, An Approach for Plant-Specific Risk-Informed Decisionmaking for Inservice Inspection of Piping, Revision 1, September 2003. RG 1.178 states that, when completed, Draft Guide DG-1122, An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed Activities will provide guidance on determining the quality of the probabilistic risk assessment (PRA) that is sufficient to provide confidence in the results such that they can be used in regulatory decisionmaking for light-water reactors. DG-1122 was issued as RG 1.200, Revision 1, in January 2005. As clarified in Regulatory Issue Summary 2007-06, Regulatory Guide 1.200 Implementation, issued on March 22, 2007, the NRC staff uses Revision 1 of RG 1.200 to assess technical adequacy for all risk-informed applications received after December 2007.

RG 1.200 describes an acceptable approach for defining the technical adequacy of an acceptable base PRA. This assessment can be performed by a licensee by directly comparing the base PRA to the supporting requirements in the endorsed American Society of Mechanical Engineers Standard RA-Sb-2005 and by addressing the NRC staff position on each item discussed in Appendix A of RG 1.200. Alternatively, a licensee can perform a self-assessment starting with the results of a previous peer review performed in accordance with the Nuclear Energy Institute (NEI) peer review process documented in NEI 00-02 and by addressing the NRC staff position on each item discussed in Appendix B of RG 1.200. The Braidwood RI-ISI RR does not discuss the technical adequacy of its PRA and, therefore, is not demonstrated to be consistent with RG 1.200. The submittal also does not provide any alternative measure of technical adequacy. Without the required information regarding the technical adequacy of the PRA, the NRC staff does not have sufficient information to begin its review.

Enclosure

In the event that Exelon submits a RI-ISI RR in the future, it must either provide a discussion demonstrating that RG 1.200 guidelines on the technical adequacy have been evaluated and satisfied, or provide and justify an acceptable alternative approach. Supporting requirements in the endorsed standard that have not been met, and all observations developed during the review(s), must be resolved or demonstrated to be unimportant to the resulting RI-ISI program.

Braidwood Station, Units 1 and 2 cc:

Braidwood Resident Inspector Corporate Distribution U.S. Nuclear Regulatory Commission Exelon Generation Company, LLC Via e-mail Via e-mail Illinois Emergency Management Agency Braidwood Distribution Division of Nuclear Safety Exelon Generation Company, LLC Via e-mail Via e-mail Will County Executive Mr. Dwain W. Alexander, Project Manager Via e-mail Westinghouse Electric Corporation Via e-mail Attorney General Springfield, IL 62701 Ms. Bridget Little Rorem Via e-mail Appleseed Coordinator Via e-mail Ms. Lorraine Creek RR 1, Box 182 Howard A. Learner Manteno, IL 60950 Environmental Law and Policy Center of the Midwest Chairman, Ogle County Board Via e-mail Via e-mail