NOC-AE-03001529, Request for Approval of ASME Section XI Code Case N-516-2 for the Second Ten-Year Inservice Inspection Interval (Relief Request RR-ENG-2-30)

Request for Approval of ASME Section XI Code Case N-516-2 for the Second Ten-Year Inservice Inspection Interval (Relief Request RR-ENG-2-30)

ML031350251
Person / Time
Site:	South Texas
Issue date:	05/08/2003
From:	Jordan T South Texas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
DG-1091, NOC-AE-03001529
Download: ML031350251 (4)

Text

Nuclear Operating Company South 7SProjc Ele'Ctfl,rrc GentinSt2?tIo PO. BoCo289 fidsith.Tex3S 77483 May 8, 2003 NOC-AE-03001529 10CFR50.55a U. S. Nuclear Regulatory Commission Attention: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852 South Texas Project Units 1 and 2 Docket Nos. STN 50498 and STN 50-499 Request for Approval of ASME Section XI Code Case N-516-2 for the Second Ten-Year Inservice Inspection Interval (Relief Request RR-ENG-2-30)

Pursuant to 10CFR50.55a(a)(3)(i), STP Nuclear Operating Company (STPNOC) hereby requests NRC approval of ASME Section XI Code Case N-516-2, "Underwater Welding," for use at the South Texas Project. Code Case N-516-2 has been conditionally accepted by the NRC in Draft Regulatory Guide DG-1091. The details of the 10CFR50.55a request are attached.

STPNOC requests approval on an expedited basis by May 22,2003, based on the schedule for reinstallation of the core barrel in the Unit 1 reactor pressure vessel during the current forced outage. Prior to approval of this request, STPNOC might perform underwater welding in accordance with Code Case N-516-2 to support removal of the Unit 1 core barrel.

If there are any questions regarding this request, please contact Michael S. Lashley at (361) 972-7523 or me at (361) 972-7902.

Vice President Engineering & Technical Services jtc

Attachment:

10CFR50.55a Relief Request RR-ENG-2-30 STI: 31605580 Atci84

NOC-AE-0300 1529 Page 2 of 2 cc:

(paper copy) (electronic copy)

Ellis W. Merschoff A. H. Gutterman, Esquire Regional Administrator, Region IV Morgan, Lewis & Bockius LLP U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 L. D. Blaylock Arlington, Texas 76011-8064 City Public Service U. S. Nuclear Regulatory Commission Mohan C. Thadani Attention: Document Control Desk U. S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike R. L. Balcom Rockville, MD 20852 Texas Genco, LP Richard A. Ratliff A. Ramirez Bureau of Radiation Control City of Austin Texas Department of Health 1100 West 49th Street C. A. Johnson Austin, TX 78756-3189 AEP Texas Central Company Cornelius F. O'Keefe Jon C. Wood U. S. Nuclear Regulatory Commission Matthews & Branscomb P. 0. Box 289, Mail Code: MN 16 Wadsworth, TX 77483 C. M. Canady City of Austin Electric Utility Department 721 Barton Springs Road Austin, TX 78704

I.-

NOC-AE-03001 529 Attachment Page 1 of2 10CFR50.55a Relief Request RR-ENG-2-30 Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

-- Alternative Provides Acceptable Level of Quality and Safety--

1 ASME Code Components Affected Pressure-retaining components or component supports, including appurtenances, subassemblies, parts of a component, and core support structures, subject to repair by undervater welding or items subject to installation as replacements by undervater welding.

2. Applicable Code Edition and Addenda American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI, 1989 Edition with no Addenda.

3. Applicable Code Requirement IWA-4000 of Section XI does not address underwater welding. However, Code Case N-516-2, "Underwater Welding,Section XI, Division 1," includes alternative procedure, performance, and filler metal qualifications, and alternative examination requirements to those contained or referenced in IWA-4000 for use when the welding is performed underwater.

4. Reason for the Request Approval of Code Case N-5 16-2 is requested for applications of underwater welding during the second ten-year inservice inspection interval at the South Texas Project. The need for approval is associated with contingency underwater welding related to removal of the core barrel from the Unit 1 reactor pressure vessel during the current forced outage.

5. Proposed Alternative and Basis for Use STP Nuclear Operating Company (STPNOC) requests relief from the requirements of IWA-4000 in accordance with 10CFR50.55a(a)(3)(i) in order to perform underwater welding for repairs or for installation of replacement items. IWA-4000 of the Section XI code of record at the South Texas Project does not address underwater welding.

. i NOC-AE-03001 529 Attachment Page 2 of 2 STPNOC requests NRC approval of ASME Section XI Code Case N-516-2 for use at South Texas on the basis that it provides an acceptable level of quality and safety.

The NRC documented their conditional acceptance of Code Case N-5 16-2 in Draft Regulatory Guide DG-1091 (Proposed Revision 13 of Regulatory Guide 1.147) published in December 2001. However, neither proposed Revision 13 nor the proposed rulemaking to reference this revision in 10CFR50.55a has been issued.

The NRC accepted Code Case N-5 16-2 subject to the following limitation in addition to the conditions specified in the Code Case:

When welding is to be performed on high neutron fluence Class 1 material, then a mockup, using material with similar fluence levels, is to be welded to verify that adequate crack prevention measures were used.

STPNOC will comply with this limitation as applicable. If alternative or additional limitations are imposed by the NRC for use of Code Case N-516-2, STPNOC will also comply with those limitations as applicable.

6. Duration of Proposed Alternative This relief request will be implemented during the second ten-year inservice inspection interval of South Texas Project Units 1 and 2. The use of Code Case N-516-2 is requested until the NRC publishes the Code Case in a future revision of Regulatory Guide 1.147.