ML080950360

Request for Additional Information, Relief Request RI-35, Proposed Alternative to Repair Requirements for Dissimilar Metal Welds for Fourth 10-Year Inservice Inspection Program Interval

ML080950360
Person / Time
Site:	Cooper
Issue date:	04/07/2008
From:	Lyon C NRC/NRR/ADRO/DORL/LPLIV
To:	Minahan S Nebraska Public Power District (NPPD)
Lyon C Fred, NRR/DORL/LPL4, 301-415-2296
References
TAC MD8025
Download: ML080950360 (5)

Text

April 7, 2008 Mr. Stewart B. Minahan Vice President-Nuclear and CNO Nebraska Public Power District 72676 648A Avenue Brownville, NE 68321

SUBJECT:

COOPER NUCLEAR STATION - REQUEST FOR ADDITIONAL INFORMATION RE: RELIEF REQUEST RI-35 (TAC NO. MD8025)

Dear Mr. Minahan:

By application dated January 30, 2008, as supplemented by letter dated March 27, 2008, Nebraska Public Power District (the licensee) requested the U.S. Nuclear Regulatory Commission (NRC) staff authorization to use an alternative to certain inservice inspection code requirements for the Cooper Nuclear Station. Specifically, Relief Request RI-35 proposed alternatives to the dissimilar metal weld repair requirements of Section XI of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code.

The NRC staff has reviewed the information provided in your supplement and determined that additional information is required in order to complete its review. Please provide a response to the enclosed questions by April 11, 2008.

The NRC staff considers that timely responses to requests for additional information help ensure sufficient time is available for staff review and contribute toward the NRCs goal of efficient and effective use of staff resources. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-2296.

Sincerely,

/RA/

Carl F. Lyon, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-298

Enclosure:

Request for Additional Information cc w/encl: See next page

ML080950360 (*)email dated OFFICE NRR/LPL4/PM NRR/LPL4/LA DCI/CVIB/BC NRR/LPL4/BC NAME FLyon JBurkhardt MMitchell (*) THiltz DATE 4/4/08 4/4/08 4/4/08 4/7/08 Cooper Nuclear Station (09/2007) cc:

Mr. Ronald D. Asche Senior Resident Inspector President and Chief Executive Officer U.S. Nuclear Regulatory Commission Nebraska Public Power District P.O. Box 218 1414 15th Street Brownville, NE 68321 Columbus, NE 68601 Regional Administrator, Region IV Mr. Gene Mace U.S. Nuclear Regulatory Commission Nuclear Asset Manager 611 Ryan Plaza Drive, Suite 400 Nebraska Public Power District Arlington, TX 76011 P.O. Box 98 Brownville, NE 68321 Director, Missouri State Emergency Management Agency Mr. John C. McClure P.O. Box 116 Vice President and General Counsel Jefferson City, MO 65102-0116 Nebraska Public Power District P.O. Box 499 Chief, Radiation and Asbestos Columbus, NE 68602-0499 Control Section Kansas Department of Health Mr. David Van Der Kamp and Environment Licensing Manager Bureau of Air and Radiation Nebraska Public Power District 1000 SW Jackson P.O. Box 98 Suite 310 Brownville, NE 68321 Topeka, KS 66612-1366 Mr. Michael J. Linder, Director Ms. Melanie Rasmussen Nebraska Department of Environmental Radiation Control Program Director Quality Bureau of Radiological Health P.O. Box 98922 Iowa Department of Public Health Lincoln, NE 68509-8922 Lucas State Office Building, 5th Floor 321 East 12th Street Chairman Des Moines, IA 50319 Nemaha County Board of Commissioners Nemaha County Courthouse Mr. Keith G. Henke, Planner 1824 N Street Division of Community and Public Health Auburn, NE 68305 Office of Emergency Coordination 930 Wildwood P.O. Box 570 Ms. Julia Schmitt, Manager Jefferson City, MO 65102 Radiation Control Program Nebraska Health & Human Services R & L Mr. Paul V. Fleming, Director of Nuclear Public Health Assurance Safety Assurance 301 Centennial Mall, South Nebraska Public Power District P.O. Box 95007 P.O. Box 98 Lincoln, NE 68509-5007 Brownville, NE 68321 Mr. H. Floyd Gilzow Mr. John F. McCann, Director Deputy Director for Policy Licensing, Entergy Nuclear Northeast Missouri Department of Natural Resources Entergy Nuclear Operations, Inc.

P.O. Box 176 440 Hamilton Avenue Jefferson City, MO 65102-0176 White Plains, NY 10601-1813

OFFICE OF NUCLEAR REACTOR REGULATION REQUEST FOR ADDITIONAL INFORMATION RELATED TO RELIEF REQUEST RI-35 NEBRASKA PUBLIC POWER DISTRICT COOPER NUCLEAR STATION DOCKET NO. 50-298 The Nuclear Regulatory Commission (NRC) staff has reviewed the Nebraska Public Power District (the licensee) March 27, 2008, Response To Request For Additional Information regarding Request RI-35, Revision 1, for the Cooper Nuclear Station (CNS) and has determined that additional information is necessary to complete the review of the licensees request for relief. Based on the staff=s review, please provide a response which addresses the following request for additional information questions.

1. The licensee has stated that the weld overlay of the dissimilar metal welds may require welding on more than 300 square inches of surface on some of the materials shown in Table 1 of Request Number RI-35, Revision 1. Provide sketches and calculations to justify the basis for the maximum surface area of weld overlay for Component Numbers RAS-BF-1, RBS-BF-1, and RAS-BF-12 shown in Table 1 of Request Number RI-35, Revision 1.

2. In Table 1 of Request Number RI-35, Revision 1, Material 1, for several components is shown as Nozzle: A-508 Class 2 CS. This implies that ASME SA-508 Class 2 is a carbon steel material (P-1 material). This is incorrect. ASME SA-508 Class 2 is a low-alloy steel material (P-3 material). As this clarification is important with respect to the qualification of the welding procedure which will be used to apply the weld overlay, please correct this discrepancy.

3. In Table 1 of Request Number RI-35, Revision 1, one of the materials to be welded is shown as, Pipe: A-155 Class 1 CS. NRC cannot find a material with this class of A-155. Please identify the material designation of this material, including material type or class and year of this designation. As noted above, documentation of this information is significant with respect to ensuring proper qualification of the welding procedure which will be used to apply the weld overlay.

4. The relief request states that full ultrasonic examination of the final weld surface and band area (1.5T width) will not be performed. Provide a sketch similar to Figure 1 in RI-35 to describe how much of the final weld surface and band area will be post-weld examined using the ultrasonic method and how much of the final weld surface and band area will be examined by the liquid penetrant method. Provide a detailed explanation for the basis that the liquid penetrant method can be substituted for the ultrasonic method in areas where the ultrasonic method will not be used.