ML121380483

Memo to File, Verbal Authorization of Relief Request ISI-17, Use of ASME Code Cases N-638-4 and N-504-4 for Alternative Repair of RHR LPCI Weld During Refueling Outage RF-18, Third 10-Year Inservice Inspection Interval

ML121380483
Person / Time
Site:	Grand Gulf
Issue date:	05/22/2012
From:	Wang A B Plant Licensing Branch IV
To:	Plant Licensing Branch IV
Wang, A B, NRR/DORL/LPLIV, 415-1445
References
TAC ME8525
Download: ML121380483 (3)

Text

May 22, 2012

MEMORANDUM TO: Docket File FROM: Alan B. Wang, Project Manager /RA/ Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

SUBJECT:

GRAND GULF NUCLEAR STATION, UNIT 1 - VERBAL AUTHORIZATION OF RELIEF REQUEST ISI-17, PROPOSED ALTERNATIVE REGARDING STRUCTURAL WELD OVERLAY (SWOL) ON THE N06-KB RESIDUAL HEAT REMOVAL SYSTEM/ LOW-PRESSURE COOLANT INJECTION "C" NOZZLE TO SAFE-END DISSIMILAR METAL WELD (TAC NO. ME8525)

By letter dated May 2, 2012, as supplemented by letter dated May 9, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML12124A245 and ML12131A408, respectively), Entergy Operations Inc. (Entergy, the licensee), submitted relief request (RR) ISI-17 for the Grand Gulf Nuclear Station, Unit 1 (GGNS) for U.S. Nuclear Regulatory Commission (NRC) review and approval.

The licensee submitted the RR under the provisions of Title 10 of the Code of Federal Regulations (10 CFR) paragraph 50.55a(a)(3)(i). In this submittal, the licensee proposed an alternative to the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),Section XI, paragraphs IWA-4411 (a) and (b), IWA-4420 and IWA-4600(b), and associated linked and branching requirements. As part of its compliance with these requirements, the licensee proposed to implement the ASME Code,Section XI, Code Cases N-504-4, "Alternate Rules for Repair of Classes 1, 2, and 3 Austenitic Stainless Steel Piping," and N-638-4, "Similar and Dissimilar Metal Welding using Ambient Temperature Machine GTAW [Gas Tungsten Arc Weld] Temper Bead Technique," as conditionally approved by the NRC. Under this RR, the licensee would perform a structural weld overlay (SWOL) using these ASME Code Cases on the N06-KB residual heat removal system (RHR)/low-pressure coolant injection (LPCI) "C" nozzle to safe-end dissimilar metal weld. The SWOL would be installed on the subject weld without removing the defect in the weld and the application of the SWOL is to arrest the growth of the existing defect while establishing a new structural pressure boundary. The licensee has made a regulatory commitment to provide a flaw evaluation as part of the technical basis to justify this repair and stated in its letter dated May 2, 2012, in part, that "preservice and inservice inspection of the weld overlay will be performed to ensure structural integrity is maintained."

The licensee provided information to demonstrate that the proposed alternative would maintain an acceptable level of quality and safety under all licensing basis conditions of operation. The NRC staff has completed its review of the information provided in the licensee's submittal for proposed alternative ISI-17 regarding the repair of RHR/LPCI "C" nozzle to safe-end dissimilar metal weld N06B-KB and concludes that the information provided by the licensee is consistent with the provisions of 10 CFR 50.55a(a)(3)(i) and supports the granting of the proposed alternative to the ASME Code requirements.

Conclusion

Pursuant to 10 CFR 50.55a(a)(3)(i), as of May 10, 2012, the NRC authorizes the licensee to implement the proposed alternative in accordance with the information provided in the licensee's letter dated May 2, 2012, and supplemented by letter dated May 9, 2012. The authorization is immediately effective for the N06-KB RHR/LPCI "C" nozzle to safe-end dissimilar metal weld and will remain in effect for during the third inservice inspection interval of the GGNS.

All other ASME Code requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.

The participants in the telephone call were:

NRC Michael Markley, Branch Chief, NRR/DORL/LPL4 Stacy Rosenberg, Branch Chief, NRR/DE/EVIB Ganesh Cheruvenki, NRR/DE/EVIB John Tsao, NRR/DE/EPNB Bob Hagar, RIV/DRP/RPB-C/ Wayne Sifre, RIV/DRS/EB-1/ Alan Wang, NRR/DORL/LPL4

Entergy Operations, Inc.

Steve Scott, Entergy Central Engineering Joe Weicks, Entergy Central Engineering Michael Briley, Entergy Central Engineering Ron Williams, Entergy Engineering Programs Jamie Gobell, Arkansas Nuclear One Project Management Dennis Wiles, GGNS Engineering Director William Simms, Entergy Services, Inc. Design Engineering Jeff Seiter, GGNS Licensing From Structural Integrity:

Moses Taylor Jr., P.E Anthony J. Giannizzi

Docket No. 50-416

ML121380483 OFFICE NRR/LPL4/PM NRR/LPL4/LA NRR/DE/EVIB/BC NRR/LPL4/BC NRR/LPL4/PM NAME AWang JBurkhardt SRosenberg MMarkley AWang (LWilkins for) -DATE 5/21/12 5/18/12 5/21/12 5/22/12 5/22/12