ML070930659

Request for Additional Information for the Review of the Wolf Creek Generating Station, Unit 1, License Renewal Application

ML070930659
Person / Time
Site:	Wolf Creek
Issue date:	04/11/2007
From:	Veronica Rodriguez NRC/NRR/ADRO/DLR
To:	Garrett T Wolf Creek
rodriguez v m, ADRO/DLR/RLRB, 415-3703
References
Download: ML070930659 (7)

Text

April 11, 2007Mr. Terry J. GarrettVice President Engineering Wolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839

SUBJECT:

REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THEWOLF CREEK GENERATING STATION, UNIT 1, LICENSE RENEWAL APPLICATION

Dear Mr. Garrett:

By letter dated September 27, 2006, Wolf Creek Nuclear Operating Corporation submitted anapplication pursuant to 10 CFR Part 54, to renew the operating license for Wolf Creek Generating Station, Unit 1, for review by the U.S. Nuclear Regulatory Commission (NRC or the staff). The staff is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review.These requests for additional information were discussed with Lorrie Bell, and a mutuallyagreeable date for the response is within 30 days from the date of this letter. If you have any questions, please contact me at 301-415-3703 or e-mail VMR1@nrc.gov

.Sincerely,/RA/Verónica M. Rodríguez, Project Manager License Renewal Branch B Division of License Renewal Office of Nuclear Reactor RegulationDocket No. 50-482

Enclosure:

Requests for Additional Informationcc w/encl: See next page

ML070930659OFFICELA:DLRPM:RLRB:DLRBC:RLRB:DLRNAMESFigueroaVRodríguezRAuluck DATE 03/4/07 04/10/07 04/11/07 WOLF CREEK GENERATING STATION (WCGS), UNIT 1LICENSE RENEWAL APPLICATION (LRA)REQUEST FOR ADDITIONAL INFORMATION (RAI)Nickel Alloy Aging Management ProgramRAI B.2.1.34-1 The Nickel Alloy Aging Management Program (AMP) was submitted prior to the performance ofpre-mitigation weld inspections for the application of weld overlays on pressurizer connections with dissimilar metal butt welds at WCGS. The pre-mitigation inspection performed in 2006 identified extensive circumferential cracking at three dissimilar metals welds associated with surge, relief, and safety nozzles. The staff requests that the applicant revise this AMP to incorporate information pertaining to the dissimilar metals butt weld inspection activities and findings. The revised AMP should: (1) discuss program enhancements incorporated as a result of the inspections, (2) provide information regarding the mitigation and preventive actions, taken or planned, to reduce the susceptibility of Alloy 600/82/182 components to primary water stress corrosion cracking (PWSCC), (3) discuss the inspection frequency and method of inspection of components susceptible to PWSCC covered under the scope of this program, and (4) provide justification that the AMP will provide reasonable assurance that PWSCC will be detected on a timely manner.In addition, the staff requests that the applicant update the AMP Updated Safety AnalysisReport (USAR) supplement to reflect all changes made to the program. RAI B.2.1.34-2 PWSCC of components made of Alloy 600/82/182 in pressurized power reactors (PWR) is anemerging material degradation issue. The industry has initiated augmented inspections and mitigation of susceptible components to ensure safe operation of the affected plants. Recent inspection findings of extensive circumferential cracking of Alloy 82/182 dissimilar metal welds at WCGS has raised concerns regarding the adequacy of the inspection scope and schedule based on industry initiatives. In addition, discussions with the industry to resolve the staff's comments and recommendations to the inspection program delineated in the Materials Reliability Program (MRP)-139, "Primary System Butt Weld Inspection and Evaluation Guideline," is continuing. Therefore, to ensure that the program is acceptable for implementation during the period of extended operation and that it will manage the effects of aging in accordance with 10 CFR 54.21(a)(3), the staff requests that the applicant commit to continue to participate in industry initiatives (such as the Westinghouse Owners Group and the Electric Power Research Institute MRP.) The program inspection requirements of Alloy 600/82/182 components must be consistent with the latest version of the NRC accepted industry guidance, generic communications, orders, and applicable regulatory requirements delineated in 10 CFR 50.55a. In addition, the staff requests that the applicant submit the AMP inspection plan for NRC review and approval at least 24 months prior to entering the period of extended operation. RAI B.2.1.34-3By letter dated October 12, 2005, the NRC staff provided comments and recommendations tothe Nuclear Energy Institute (NEI) pertaining to the guidance provided in MRP-139 for the inspection and evaluation of Alloy 82/182 butt welds. This initiative is continuing and a resolution has not been reached. The staff requests that the applicant identify any exceptions that WCGS plans to take to the NRC's comments and recommendations provided to the NEI. If WCGS plans to take exceptions, the staff requests that the applicant provide its technical justification.RAI B.2.1.34-4By letter dated July 27, 2004, Wolf Creek Nuclear Operating Corporation (WCNOC) respondedto NRC Bulletin 2004-01, "Inspection of Alloy 82/182/600 Materials Used in the Fabrication of Pressurizer Penetrations and Steam Space Piping Connections at Pressurized Water Reactors." The staff requests that the applicant confirm that WCGS is not taking any exception to the guidance provided in this bulletin. If exceptions are identified, the applicant should address and justify them, especially those in the following areas: (1) percentage of inspection coverage to be achieved at each location, and (2) performance of an extent-of-condition evaluation, sample expansion, and non-destructive examinations if circumferential cracking is found. In addition, in view of the extensive PWSCC found at WCGS, the staff requests that the applicant discuss any enhancements made to the WCGS inspection plan for those components addressed in Bulletin 2004-01.RAI B.2.1.34-5NRC Bulletin 2003-02, "Leakage from Reactor Pressure Vessel Lower Head Penetrations andReactor Coolant Pressure Boundary Integrity," requested information from PWR licensees regarding the reactor coolant pressure boundary integrity associated with the reactor pressure vessel lower head penetrations. WCNOC did not discuss augmented inspection plans for these components in its response to this bulletin nor in its description of the AMP. In view of the extensive PWSCC found at WCGS, the staff requests that the applicant discuss the inspection plan for the components addressed in Bulletin 2003-02, and provide justification for its adequacy.RAI B.2.1.34-6The LRA states that the reactor coolant system (RCS) pressure boundary, RCS non-pressureboundary, and ESF locations are included within the scope of this AMP. The staff requests that the applicant identify the components associated with these locations and its corresponding inspection plan. In addition, the staff requests that the applicant identify any Alloy 600/82/182 components not covered within the scope of this program and the reasons for their exclusion.RAI B.2.1.34-7The detection of aging effects program element states that this AMP utilizes various visual,surface and volumetric inspections and examination techniques for early detection of PWSCC in Alloy 600 components. However, it does not specify whether the equipment, method and personnel used for these inspections meet the ASME Code Section XI requirements. The staffrequests that the applicant revise the LRA to clarify this statement. RAI B.2.1.34-8The monitoring and trending program element states that relative risk rankings for Alloy 600locations are included as part of this AMP. The staff requests that the applicant address how the relative risk rankings will be used in the inspection of Alloy 600/82/182 components and whether this ranking methodology was approved by the NRC. RAI B.2.1.34-9The corrective actions program element states that "Corrective actions may be used as trackingand documentation records for changes in plant thought processes and to identify potential improvement in programs from benchmarking activities." The staff requests that the applicant provide details and examples to clarify this statement.

Letter to T. Garrett from V. Rodriguez, dated April 11, 2007DISTRIBUTION:

SUBJECT:

REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THEWOLF CREEK GENERATING STATION, UNIT 1, LICENSE RENEWAL APPLICATIONHARD COPY DLR RF E-MAIL:PUBLICRWeisman GGalletti DShum SSmith (srs3)

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CJacobs JDonohew GPick, RIV SCochrum, RIV Wolf Creek Generating Station cc:Jay Silberg, Esq.Pillsbury Winthrop Shaw Pittman, LLP 2300 N Street, NW Washington, DC 20037Regional Administrator, Region IVU.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-7005Senior Resident InspectorU.S. Nuclear Regulatory Commission P.O. Box 311 Burlington, KS 66839Chief Engineer, Utilities DivisionKansas Corporation Commission 1500 SW Arrowhead Road Topeka, KS 66604-4027Office of the GovernorState of Kansas Topeka, KS 66612Attorney General120 S.W. 10 th Avenue, 2 nd FloorTopeka, KS 66612-1597County ClerkCoffey County Courthouse 110 South 6 th StreetBurlington, KS 66839Thomas A. Conley, Section ChiefRadiation and Asbestos Control Kansas Department of Health and Environment Bureau of Air and Radiation 1000 SW Jackson, Suite 310 Topeka, KS 66612-1366Vice President Operations/Plant ManagerWolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839Supervisor LicensingWolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839U.S. Nuclear Regulatory CommissionResident Inspectors Office/Callaway Plant

8201 NRC Road Steedman, MO 65077-1032Kevin J. Moles, ManagerRegulatory Affairs Wolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839Lorrie I. Bell, Project ManagerWolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839Mr. James RossNuclear Energy Institute 1776 I Street, NW, Suite 400 Washington, DC 20006-3708