ML12359A061
| ML12359A061 | |
| Person / Time | |
|---|---|
| Site: | Mcguire |
| Issue date: | 12/06/2012 |
| From: | Capps S Duke Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML12359A061 (5) | |
Text
Duke STEVEN D CAPPS DEnergy Vice President McGuire Nuclear Station Duke Energy MGO1 VP / 12700 Hagers Ferry Rd.
Huntersville, NC 28078 980-875-4805 980-875-4809 tax Steven. Capps @duke-energy. corn December 6, 2012 10 CFR 50.55a U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001
Subject:
Duke Energy Carolinas, LLC (Duke Energy)
McGuire Nuclear Station, Unit 2 Docket No. 50-370 Relief Request Serial # 12-MN-002, Response to Request for Additional Information on Limited Weld Examinations during Refueling Outage 2EOC20 By letter dated January 11, 2012, as supplemented by letter dated April 23, 2012, Duke Energy submitted the subject relief request requesting relief from the volumetric coverage requirement for weld examinations specified in the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section Xl. This relief is requested for the McGuire Unit 2 third 10-year inservice inspection interval.
On October 16, 2012, the Nuclear Regulatory Commission staff electronically requested additional information regarding this relief request. Please find enclosed Duke Energy's response to your request for additional information.
If you have any questions or require additional information, please contact P. T. Vu at (980) 875-4302.
Sincerely, Steven D. Capps Enclosure wlm. duke-energy corn
U. S. Nuclear Regulatory commission December 6, 2012 Page 2 xc:
V. M. McCree, Region II Administrator U. S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, GA 30303-1257 J. H. Thompson, Project Manager U. S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop O-8G9A Rockville, MD 20852-2738 J. Zeiler NRC Senior Resident Inspector McGuire Nuclear Station
Relief Request 1 2-MN-002, Response to NRC Request for Additional Information Page 1 of 3 Enclosure McGuire Nuclear Station Unit 2 Relief Request 12-MN-002 Request for Additional Information (RAI) 2EOC-20 Limited Weld Exam Duke Energy Response
Relief Request 1 2-MN-002, Response to NRC Request for Additional Information Page 2 of 3 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION Question:
RR 12-MN-002 stated that due to limitations or interference, a relief is requested for the subject weld from the required RI-ISI examination coverage (greater than 90% of the ASME Code required volume). The staff notes that when the RI-ISI program is established, the welds shall be selected such that the ASME Code required examination coverage is achievable. Discuss whether there were other welds with the same risk-significance, subject to the same degradation mechanism that could be examined and achieved the required examination coverage. If the answer is yes, then will the licensee substitute that weld for the subject weld in its RI-ISI program update?
Duke Energy Response:
There are other welds with the same risk-significance, subject to the same degradation mechanism that could be examined. Examination coverage for these welds will be evaluated.
The program will be updated to examine another weld in the next refueling outage to attempt to obtain required examination coverage. The actual examination coverage will not be known until the examination is performed.
Relief Request 1 2-MN-002, Response to NRC Request for Additional Information Page 3 of 3 COMMITMENT Commitment Due Date Another weld in the RI-ISI program with the During next scheduled Unit 2 Refueling same risk-significance and subject to the same Outage in spring 2014.
degradation mechanism as the weld in this relief request will be examined in the next refueling outage.