L-PI-08-041, Additional Commitment Regarding 10 CFR 50.55a Request: Proposed Alternatives for Application of Structural Weld Overlay to the Prairie Island Nuclear Generating Plant Unit 2 Pressurizer Surge Nozzle Weld (2-RR-4-8)
| ML081280890 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 05/07/2008 |
| From: | Wadley M Nuclear Management Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-PI-08-041, TAC MD5868 | |
| Download: ML081280890 (2) | |
Text
May 7,2008 L-PI-08-041 10 CFR 50.55a U S Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Prairie lsland Nuclear Generating Plant Unit 2 Docket 50-306 License No. DPR-60 Additional Commitment Regarding 10 CFR 50.55a Request: Proposed Alternatives for Application of Structural Weld Overlay to the Prairie lsland Nuclear Generating Plant Unit 2 Pressurizer Surge Nozzle Weld (2-RR-4-81
/TAC MD5868)
References:
I ) Letter from MD Wadley (NMC) to Document Control Desk (NRC), L-PI-07-054, "10 CFR 50.55a Request: Proposed Alternatives for Application of Structural Weld Overlay to the Prairie lsland Nuclear Generating Plant Unit 2 Pressurizer Surge Nozzle Weld (2-RR-4-8)," dated June 25, 2007 (ML071760332)
- 2) Letter from MD Wadley (NMC) to Document Control Desk (NRC), L-PI-08-003, "Response to Request for Additional Information Regarding 10 CFR 50.55a Request for Relief from ASME Section XI Repair and Replacement Requirements: Proposed Alternatives for Application of Structural Weld Overlay to the Prairie lsland Nuclear Generating Plant Unit 2 Pressurizer Surge Nozzle Weld (2-RR-4-8) (TAC MD5868)," dated January 15, 2008 By letter dated June 25,2007 (Reference I), and pursuant to 10 CFR 50.55a(a)(3), Nuclear Management Company, LLC, (NMC) requested U.S. Nuclear Regulatory (NRC) staff review and approval of 10 CFR 50.55a Request 2-RR-4-8, Revision 0, for the Prairie lsland Nuclear Generating Plant (PINGP) Unit 2. Request 2-RR-4-8 allows the installation of a full structural weld overlay on the pressurizer surge line nozzle-to-safe end dissimilar metal and safe end-to-reducer stainless steel butt welds. The overlay is a pre-emptive measure addressing primary water stress corrosion cracking (PWSCC) concerns identified by the industry for welds associated with Alloy 600/82/182 components exposed 171 7 Wakonade Drive East Welch, Minnesota 55089-9642 Telephone: 651.388.1 121
Document Control Desk Page 2 to primary coolant. The original 10 CFR 50.55a request was supplemented with responses to NRC requests for additional information (RAI) and a revised 10 CFR 50.55a request (2-RR-4-8, Revision 1) on January 15, 2008 (Reference 2).
The purpose of this letter is to provide an additional commitment regarding the inservice inspection requirements in the subject 10 CFR 50.55a request. This commitment is based on an April 29, 2008, telephone conversation with the NRC Project Manager and the assigned reviewer. Based on this conversation, NMC commits to perform the first inservice inspection of the Unit 2 Pressurizer Surge Line Nozzle Weld Overlay during the first or second refueling outage following the overlay installation if flaws are identified in the pre-overlay ultrasonic examination. Scheduling the inservice inspection of the Unit 2 Pressurizer Surge Line Nozzle Weld Overlay during the first or second refueling outage following the weld overlay installation is similar to the inservice inspection scheduling requirements of Nonmandatory Appendix Q, Article Q-4300. This additional commitment is summarized below.
NMC continues to request approval of the 10 CFR 50.55a request by June I, 2008. This date is based on the next Prairie Island Unit 2 refueling outage scheduled for Fall 2008. A June I, 2008, approval allows NMC to sufficiently plan and prepare the pre-emptive weld overlay activities in advance of the refueling outage. If you have questions regarding this 10 CFR 50.55a request, please contact Lynne Gunderson at 715-377-3430.
Summary of Commitments This letter contains one new commitment. This letter does not revise any existing commitments. The new commitment is:
- 7. NMC commits to perform the first inservice inspection of the Unit 2 Pressurizer Surge Line Nozzle Weld Overlay during the first or second refueling outage following the overlay installation if flaws are identified in the p,re-overlay ultrasonic examination.
Michael D. CWadley Site Vice President, Prairie lslan clear Generating Plant Nuclear Management Company, cc:
Administrator, Region Ill, USNRC Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Chief Boiler Inspector, State of Minnesota