ML13051A385

Three Mile Island Nuclear Station, Unit 1 - Request for Additional Information Regarding End-of-Interval Relief Request RR-12-01, Pressure Nozzle-to-Head Weld Exams (TAC No. ME9788)

ML13051A385
Person / Time
Site:	Three Mile Island
Issue date:	02/25/2013
From:	Bamford P J Plant Licensing Branch 1
To:	Pacilio M J Exelon Nuclear
Bamford P J
References
TAC ME9788, RR-12-01
Download: ML13051A385 (4)

Text

UNITED NUCLEAR REGULATORY WASHINGTON, D.C. 20555-0001 February 25, 2013 Mr. Michael J. Pacilio President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555 THREE MILE ISLAND NUCLEAR STATION, UNIT 1 -REQUEST FOR ADDITIONAL INFORMATION REGARDING END-OF-INTERVAL RELIEF REQUEST RR-12-01, PRESSURIZER NOZZLE-TO-HEAD WELD EXAMS (TAC NO. ME9788) Dear Mr. Pacilio: By letter dated October 5, 2012 (Agencywide Documents Access and Management System Accession No. ML 12283A252), Exelon Generation Company, LLC (Exelon, the licensee) submitted a relief request for U.S. Nuclear Regulatory Commission (NRC) approval. In the relief request, Exelon identifies the limited examination of three pressurizer relief nozzle welds at Three Mile Island Nuclear Station for the third inservice inspection interval, which ended on April 19,2012. According to the licensee, the coverage for each of the welds in question was approximately 40 percent, as compared to a specification of 90 percent, in accordance with American Society of Mechanical Engineers Code Case N-460, "Alternative Examination Requirements for Class 1 and Class 2 Welds,Section XI, Division 1." The NRC staff has been reviewing the submittal and has determined that additional information is needed to complete its review. The specific question is found in the enclosed request for additional information (RAI). The question was sent via electronic transmission on February 19, 2013, to Mr. Thomas Loomis, of your staff. The draft question was sent to ensure that it was understandable, the regulatory basis was clear, and to determine if the information was previously docketed. The RAI was discussed with Mr. Loomis on February 20, 2013, where it was agreed that no clarification teleconference was necessary, and that a response would be submitted by March 29, 2013.

M. Pacilio -2 Please contact me at 301-415-2833, if you have any questions. Sincerely. Peter Bamford, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-289 Enclosure: As stated cc: Distribution via Listserv REQUEST FOR ADDITIONAL INFORMATION THREE MILE ISLAND NUCLEAR STATION, UNIT 1 END-OF-INTERVAL RELIEF REQUEST RR-12-01 PRESSURIZER NOZZLE-TO-HEAD WELD EXAMS DOCKET NO. 50-289 By letter dated October 5, 2012 (Agencywide Documents Access and Management System Accession No. ML 12283A252), Exelon Generation Company, LLC (Exelon, the licensee) submitted a relief request for U.S. Nuclear Regulatory Commission (NRC) approval. In the relief request, Exelon identifies the limited examination of three pressurizer relief nozzle welds at Three Mile Island Nuclear Station for the third inservice inspection interval, which ended on April 19, 2012. According to the licensee, the coverage for each of the welds in question was approximately 40 percent, as compared to a specification of 90 percent, in accordance with American Society of Mechanical Engineers Code Case N-460, "Alternative Examination Requirements for Class 1 and Class 2 Welds,Section XI, Division 1." The U.S. Nuclear Regulatory Commission (NRC) staff has been reviewing the submittal and has determined that additional information is needed to complete its review. The submittal does not include any statement regarding past inspection results, including preservice. The NRC staff is concerned that there could be a weld repair done during fabrication. If the repair used a Nickel-based alloy filler metal, the joint could be susceptible to primary water stress corrosion cracking. Therefore, describe the results of all past inspections, including preservice, as well as any repairs that have been done to the subject pressurizer relief nozzle-to-vessel welds. Enclosure M. Pacilio Please contact me at 301-415-2833, if you have any Docket No. 50-289 As cc: Distribution via Listserv DISTRIBUTION: RidsNrrPMThreeMilelsland Resource RidsAcrsAcnw MailCTR Resource RidsRgn1 MailCenter Resource PPurtscher. NRR ADAMS Accession Number' ML 13051A385 Sincerely, Ira! Peter Bamford, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation PUBLIC LPLI-2 R/F RidsNrrLAABaxter Resource RidsOgcRp Resource RidsNrrDorlDpr Resource RidsNrrDorlLpl1-2 Resouce RidsNrrDeEvib Resource *via email OFFICE LPL1*21PM LPL1-21LA DE/EVIB/BC LPLI*2/BC NAME PBamford ABaxter* SRosenberg* MKhanna DATE EO/13 02/22/13 02115113 2125113 OFFICIAL RECORD COPY