ML13277A555
| ML13277A555 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 10/08/2013 |
| From: | James Kim Plant Licensing Branch 1 |
| To: | Heacock D Dominion Nuclear Connecticut |
| Kim J | |
| References | |
| TAC MF1405 | |
| Download: ML13277A555 (3) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Mr. David A. Heacock President and Chief Nuclear Officer Dominion Nuclear Connecticut, Inc.
lnnsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711 October 8, 2013
SUBJECT:
MILLSTONE POWER STATION, UNIT 2-REQUEST FOR ADDITIONAL INFORMATION REGARDING RELIEF REQUEST RR-04-15 (TAC NO. MF1405)
Dear Mr. Heacock:
By letter dated April 9 2013, Dominion Nuclear Connecticut, Inc. (the licensee) submitted alternative request RR-4-15 covering eight cold leg dissimilar metal welds from the requirements of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code) Case N-770-1 "Alternative Examination Requirements and Acceptance Standards for Class 1 PWR Piping and Vessel Nozzle Butt Welds Fabricated With UNS N06082 or UNS W86182 Weld Filler Material With or Without Application of Listed Mitigation Activities." The licensee stated that achieving 100 percent of the ASME Code Case N-770-1-required volumes, for the welds would result in a hardship or unusual difficulty without a compensating increase in the level of quality or safety. The request for relief applies to the fourth 1 0-year in service inspection interval at Millstone Power Station Unit 2.
Based on information received on a discussion with the licensee on September 16, 2013, it has been determined that the initial Request for Additional Information (RAI) dated August 22, 2013 was insufficient. The enclosed RAI supersedes the RAI sent on August 22, 2013. A response to this RAI is requested to be provided by February 28, 2014.
If you have any questions regarding this matter, please contact me at 301-415-4125.
Docket No. 50-336
Enclosure:
As stated cc w/encl: Distribution via Listserv Sincerely, James Kim, Project Manager Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
REQUEST FOR ADDITIONAL INFORMATION REGARDING MILLSTONE POWER STATION, UNIT 2 RELIEF REQUEST RR-04-15 DOCKET NO. 50-336 In accordance with Title 10 of the Code of Federal Regulations (1 0 CFR) 50.55a(a)(3)(ii), the licensee has submitted the request for alternative for limited examinations of dissimilar metal welds. The licensee stated that achieving 100 percent of the American Society of Mechanical Engineers (ASME) Code Case N-770-1 required volumes, for the welds would result in a hardship or unusual difficulty without a compensating increase in the level of quality or safety.
The staff has reviewed and evaluated the information provided by the licensee and has determined that the following information is needed in order to complete its review of the request.
- 1. In order to evaluate the proposed alternative, the NRC staff requires the details of the Appendix VIII-qualified inspection procedure that is to be used on the welds described in RR-04-15 during the Spring 2014 outage a Millstone Power Station Unit 2. Specifically, the following items are required to evaluate the proposed alternative:
- a. Provide the inspection angles that are to be used by the phased array probe to insonify the welds during the examination.
- b. Provide the specific inspection angles that are to be used to calculate coverage.
- c.
Provide the Performance Demonstration Qualification Summary describing the procedure and any limitations placed on the ASME Code Section XI, Appendix VIII-qualified procedure.
- d. Describe the modifications, if any, made to the procedure using the site-specific mockup process.
- 2. Provide tables showing the total expected inspection coverage and diagrams showing the expected inspection coverage that will be for both the obstructed and unobstructed regions of the welds using the procedure described in Question 1.
- 3. Appendix A of the 2013 report by the Electric Power Research Institute "Nondestructive Evaluation: Guideline for Conducting Ultrasonic Examinations of Dissimilar Metal Welds, Revision 1" contains a flow chart detailing when encoded examinations should be used for dissimilar metal welds. This guidance on the use of encoded scanning is an NEI-03-08 "Needed" requirement for the first inspection after January 2014. Based on the inspection plans and the EPRI guidance, identify which welds will be inspected using encoded and which will be inspected using non-encoded techniques?
Enclosure
- See memo dated October 3 2013 I
OFFICE LPL 1-1/PM LPL 1-1/LA DE/EPNB/BC LPL 1-1/BC (A)
NAME JKim KGoldstein Tlupold*
RBeall DATE 10/8/13 10/7/2013 10/3/2013 10/8/13