NL-04-1123, Request to Revise Reg Guide 1.190 Implementation Date

Request to Revise Reg Guide 1.190 Implementation Date

ML041980046
Person / Time
Site:	Hatch
Issue date:	07/13/2004
From:	Sumner H Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NL-04-1123, RG-1.190, TAC MB6106, TAC MB6107
Download: ML041980046 (3)

Text

H.L Sumner. Jr. Southern Nuclear Vice President Operating Company, Inc.

Hatch Project Post Office Box 1295 Birmingham, Alabama 35201 Tel 205.992.7279 SOUTHERNAE..

July 13, 2004 COMPANY Energy to Serve Your World Docket Nos.: 50-321 NL-04-1123 50-366 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Edwin I. Hatch Nuclear Plant Request to Revise Reg Guide 1.190 Implementation Date Ladies and Gentlemen:

This letter requests a revision to the Southern Nuclear Operating Company's (SNC) commitment for Plant Hatch to begin using an RPV neutron fluence methodology that is compliant with Regulatory Guide (RG) 1.190 by December, 15, 2004. SNC requests the date be changed to July 31, 2007.

This commitment was made as part of the Plant Hatch conversion, by license amendment, to the Integrated Surveillance Program (ISP) for reactor vessel surveillance capsules in a letter dated January 8, 2003. The NRC accepted the commitment in their SER for the Hatch ISP dated March 10, 2003 (TAC Nos. MB 6106 and MB 6107).

SNC plans to use the RAMA methodology for its calculations of Plant Hatch reactor vessel and internals fluence. However, RAMA has not yet been approved by NRC and the ultimate approval date is uncertain, but it may likely not be approved by December of 2004. Alternatively, Hatch could seek another method of compliance such as using some other RG 1.190 compliant methodology. However, since SNC's intent is to use the RAMA code once it is approved, expending the necessary resources for an interim program would represent an undue hardship.

The RAMA fluence methodology and technical bases have been submitted to NRC via various BWRVIP submittals. The NRC has requested further information on the submittals and BWRVIP member utilities are currently reviewing the proposed responses before they are sent to NRC. The BWRVIP has requested that utilities review the responses by July 9, 2004, at which time resolution of comments will commence. The formal submittal of the responses by the BWRVIP will depend on the quantity and the nature of the comments. This submittal may not occur until sometime in August or later.

Consequently, it is uncertain when NRC approval of the RAMA methodology will ultimately be received. Until this approval is obtained, uncertainties associated with plant specific application of a new neutron fluence methodology warrant a delay in the plant specific model development implementing RAMA. Once RAMA is approved, additional work will be needed to finalize fluence calculations for both Hatch reactor vessels.

DO

U. S. Nuclear Regulatory Commission NL-04-1123 Page 2 In the March, 2003 SER, NRC stated that the December, 2004 date was acceptable since the Hatch Pressure/Temperature (PT) curves are valid up to 54 Effective Full Power Years (EFPY) and are expected to remain conservative with respect to actual accumulated neutron flux through the December, 2004 date. However, the date was an arbitrary projection based on the anticipated approval of the RAMA code. The current fuel cycle projection for Plant Hatch Units I and 2 by the implementation date proposed herein is 24 and 22 EFPY, respectively. Therefore, the current PT curves have sufficient margin to remain conservative up through the projected date for implementation of an approved fluence methodology. Currently, Plant Hatch Unit I is at 21 EFPY and Unit 2 is at 19 EFPY.

In summary, due to the uncertainties in the review and ultimate approval of the RAMA code, and because the Hatch Unit I and 2 PT curves will remain conservative through the proposed date, Southern Nuclear requests a change in the commitment to begin using a RG 1.190 compliant methodology from December of 2004 to July 31, 2007.

The NRC commitments contained in this letter are provided as a table in the attachment.

If you have any questions, please advise.

Respectfully submitted, SOUTHERN NUCLEAR OPERATING COMPANY H. L. Sumner, Jr.

HLS/OCV/daj Attachment cc: Southern Nuclear Operating Company Mr. J. B. Beasley, Jr., Executive Vice President Mr. G. R. Frederick, General Manager - Plant Hatch RType: CHAO2.004 U. S. Nuclear Regulatory Commission Dr. W. D. Travers, Regional Administrator Mr. C. Gratton, NRR Project Manager - Hatch Mr. D. S. Simpkins, Senior Resident Inspector - Hatch State of Georgia Mr. L. C. Barrett, Commissioner - Department of Natural Resources

Attachment Edwin I. Hatch Nuclear Plant, Units I and 2 Request to Revise Reg Guide 1.190 Implementation Date List of Reiulatorv Commitments The following table identifies those actions committed by Southern Nuclear Operating Company in this document. Any other statements in this submittal are provided for information purposes and are not considered to be regulatory commitments.

TYPE SCHEDULED (Check one) COMPLETION ONE-TIME CONTINUING DATE COMMITMENT ACTION COMPLIANCE (If Required)

Plant Hatch will begin using a neutron fluence methodology that is compliant with Regulatory Guide X July 31, 2007 1.190 by the date shown on this Table.