ML15195A423

Request for Relief from Code Case N-770-1, Subsection 2400 and Table 1 Inspection Frequency of Reactor Vessel Cold Leg Nozzle to Safe-End Welds with Flaw Analysis Supplement (Relief Request RR-ENG-3-17)

ML15195A423
Person / Time
Site:	South Texas
Issue date:	06/25/2015
From:	Berg M South Texas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NOC-AE-l15003268, STI: 34150859, TAC MF6174
Download: ML15195A423 (6)

Text

Nuclear Operating Company South Texas Pro/eot Electric GeneratingStation P.O. Box 289 Wadsworth. Texas 77483 ,v v -

June 25, 2015 NOC-AE-l15003268 10 CFR 50.55a File No. G25 U. S. Nuclear Regulatory Commission Attention: Document Control Deskk Washington, DC 20555-0001 South Texas Project Unit 1 Docket No. STN 50-498 Request for Relief from Code Case N-770-1, Subsection 2400 and Table 1 Inspection Frequency of Reactor Vessel Cold Leg Nozzle to Safe-end Welds with Flaw Analysis Supplement (Relief Reauest RR-ENG-3-17' 1 ........... i .......... ... . .. r

References:

1. Letter from Michael Berg, STPNOC, to NRC Document Control Desk, "Request for Relief from Code Case N-770-1, Subsection 2400 and Table I Inspection Frequency of Reactor Vessel Cold Leg Nozzle to Safe-end Welds with Flaw Analysis", April 24, 2015. (NOC-AE-1 5003250) (ML15133A130)

2. Email from Lisa Regner, NRC to Lance Sterling, STPNOC, "DRAFT SouthTexas-1 RAI N-770-1 RPV Cold Leg Nozzles (MF6174)," dated June 18, 2015. (ML15170A066)

In accordance with the provisions of 10 CFR 50.55a(a)(3)(ii), STP Nuclear Operating Company (STPNOC) requested relief for South Texas Project (STP) Unit 1 for performing the reactor vessel Cold Leg nozzle to safe-end weld inspections in Reference 1. Subsequently, in Reference 2, the NRC provided feedback to STPNOC related to the need of enhancing the original submittal with additional clarification information. The intent of the letter is to provide a Supplement to the original Relief Request (Reference 1) to address the additional clarifications.

This letter contains one enclosure that is considered non-proprietary. There are no commitments in this letter.

Ao4~1 ST1" 34150859

NOC-AE-1 5003268 Page 2 of 3 If there are any questions regarding this Relief Request, please contact Rafael Gonzales at 361-972-4779, or me at 361-972-7030.

Manager Design Engineering!

Testing and Programs rjg

Enclosure:

Supplement Response Related to the Request for Relief from Code Case N-770-I, Subsection 2400 and Table 1 Inspection Frequency of Reactor Vessel Cold Leg Nozzle to Safe-end Welds with Flaw Analysis

NOC-AE-1 5003268 Page 3 of 3 cc:

(paper copy)

(electronic copy)

Regional Administrator, Region IV Morgan, Lewis & Bockius LLP U.S. Nuclear Regulatory Commission Steve Frantz 1600 East Lamar Boulevard Arlington, TX 76011-4511 U.S. Nuclear Regulatory Commission Lisa M. Regner Lisa M. Regner Senior Project Manager U.S. Nuclear Regulatory Commission NRG South Texas LP One White Flint North (MS 8 G9A) John Ragan 11555 Rockville Pike Chris O'Hara Rockville, MD 20852 Jim von Suskil NRC Resident Inspector CPS Energy U. S. Nuclear Regulatory Commission Kevin Polio P. 0. Box 289, Mail Code: MN1 16 Cris Eugster Wadsworth, TX 77483 L. D. Blaylock Crain Caton & James, P.C.

Peter Nemeth City of Austin Cheryl Mele John Wester Texas Dept. of State Health Services Richard A. Ratliff Robert Free

NOC-AE-1 5003268 Enclosure Supplement Response Related to the Request for Relief from Code Case N-770-1, Subsection 2400 and Table 1 Inspection Frequency of Reactor Vessel Cold Leg Nozzle to Safe-end Welds with Flaw Analysis

NOC-AE-1 5003268 Enciosure Page 1 of 2 Backgqround By letter dated April 24, 2015 (ADAMS Number ML15133A130), STP Nuciear Operating Company (the licensee) requested relief from requirements of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (B&PV Code) for the volumetric examination of the reactor pressure vessel (RPV) cold leg nozzle dissimilar metal (DM) butt welds at the South Texas Project (South Texas), Unit 1.

To complete its review, the NRC staff requests the following additional information.

1. When did the licensee complete the ASME Code Case N-770-1 baseline examination of these welds, as required by 10 CFR 50.55a(g)(6)(ii)(F)(1) with conditions?

2. (a) Clarify that the proposed alternative is to defer the ASME Code Case N-770-1 required volumetric examination, as required by 10 CFR 50.55a(g)(6)(ii)(F) with conditions, from the fall 2015 refueling outage (1IRE19) up to and including the spring 2017 refueling outage (1 RE20). (b) Clarify that the discussions regarding non-welded stress improvement provided in the relief request and the information provided in Table 2, page 6 of Enclosure 1 of relief request, are for information only and not part of the licensee's proposed alternative.

NRC Issue

1. When did the licensee complete the ASME Code Case N-770-1 baseline examination of these welds, as required by 10 CFR 50.55a(g)(6)(ii)(F)(1) with conditions?

STPNOC Response The ASME Code Case N-770-1 baseline examination of these welds, as required by 10 CFR 50.55a(g)(6)(ii)(F)(1), were performed in Unit 1 during the Fall of 2009.

NOC-AE-1 5003268 Enclosure Page 2 of 2 NRC Issue

2. (a) Clarify that the proposed alternative is to defer the ASME Code Case N-770-1 required volumetric examination, as required by 10 CFR 50.55a(g)(6)(ii)(F) with conditions, from the fall 2015 refueling outage (I RE 19) up to and including the spring 2017 refueling outage (I1RE20). (b) Clarify that the discussions regarding non-welded stress improvement provided in the relief request and the information provided in Table 2, page 6 of Enclosure I of relief request, are for information only and not part of the licensee's proposed alternative.

STPNOC Response (a) The proposed alternative is to defer the ASME Code Case N-770-I required volumetric examination, as required by 10 CFR 50.55a(g)(6)(ii)(F) with conditions, from the fall 2015 refueling outage (1IRE19) up to and including the spring 2017 refueling outage (1RE20). Essentially, this Relief Request (Reference 1) submittal is a nominal 18 month extension request, i.e. one operating cycle.

(b) This information provided in Table 2, page 6 of Enclosure 1 of the Relief Request (Reference I of the Supplement), is provided for information only and is not a part of STPNOC's proposed alternative.