ML20086N429

Forwards Rept NSD-TAP-1131, Responses to NRC Questions on Steam Generator Operating Cycle Evaluation for North Anna Unit 1, in Response to NRC 911107 Request for Addl Info. Rept Withheld (Ref 10CFR2.790)

ML20086N429
Person / Time
Site:	North Anna
Issue date:	12/09/1991
From:	Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML19351A940	List: ET-NRC-91-3642, Requests That Encl Rept NSD-TAP-1131, Response to NRC Questions on Steam Generator Operating Cycle Evaluation for North Anna 1, Be Withheld (Ref 10CFR2.790) ML20086N429
References
91-693B, NUDOCS 9112200180
Download: ML20086N429 (2)

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. 3 WmINIA 15MICTHIC AND l' owl:R CObiPANY u n c n >t o x u, Vi nmNi A 200M December 9,1991 U.S. Nuclear Regulatory Commission Serial No. 91-6938 Attention: Document Control Desk NL&P/JBL: R0 Washington, D.C. 20555 Docket No. 50-338 License No. NPF-4 Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNIT 1 STEAM GENERATOR _ OPERATING CYCLE EVALUATION RESPONSE TO NRC REQUEST FOR ADDIT.lONAL INFORMATION By letter dated November 7,1991, the NRC requested additional information regarding our North Anna Unit 1 Steam Generator Operating Cycle Evaluation Report, i.e., Westinghouse report NSD-TAP-1093/SG 91-07-043 (Proprietary), which was submitted by Virginia Electric and Power Company letter dated August 6,1991 (Serial No. 91-337A). Proprietary and non-proprietary versions of this report, entitled " North Anna Unit 1 Stecm Generator Operating Cycle Evaluation," WCAP-13034 and WCAP-13035, respectively, were subsequently provided by Virginia Electric and Power Company letter dated August 30,1991 (Serial No. 91-337B).

During our December 2,1991 meeting at the NRC offices in White Flint, we presented responses to the NRC concerns by addressing the primary issues in your November 7, 1991 request for additionalinformation. Further, summary responses to each question were left with the staff at the close of the meeting. The attachment to this letter follows up that communication with our detailed written responses.

The Westin0house report provided analysis and discussion which technically supports a full-cycle (18 months) of operation for the North Anna Unit 1 steam generators for the current operating cycle. However, we continue to emphasize that our outage schedule limits the current operatirig cycle to approximately 13 inonths (i.e., until April 18,1992).

We have reviewed the results of the evaluation with regard to the NRC questions and concluded that no safety issues or concerns exist for North Anna Unit 1 for the additional three months of operation without a mid cycle outage. A discussion of our basis for this conclusion was provid9d in our letter to the NRC dated December 5, 1991 (Serial No. 91-693A).

Enclosed with this letter are ten copies of Westinghouse report NSD-TAP-1131, entitled " Responses to NRC Ouestions on the Steam Generator Operating Cycle Evaluation for North Anna Unit 1," which provides our response to the NRC's request for additional information relative to Westinghouse report NSD-TAP-1093/SG-91 043. The attached report contains iriformation which is proprietary to Westinghouse 011 2001w 2112 E _ ~ Il[

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Electric Corporation. Accordingly,it is requested that this information be withheld from public disclosure. Westinghouse will comply with the requirements of 10 CFR 2.790 to provide proprietary and non proprietary versions of the above material together with an affidavit as soon as the proprietary information contained in the submittal has been specifically identified and the proprietary and non proprietary versions have been prepared. Copies of the proprietary and non proprietary versions of the information and the required affidavit will be submitted within four weeks. Also attached is a Westinghouse letter requesting the Westinghouse report, NSD-TAP-1131, be withheld as proprietary information.

Correspondence with respect to the proprietary aspects of this submittal should be addressed to R. P. DiPiazza, Manager of Operating Plant Licensing Support, Westinghouse Electric Corporation, P.O. Box 355, Pittsburgh, Pennsylvania 15230-0355.

Should you have any questions, please contact us.

Very truly yours, A ,- p 3 Mb W. L. Stewart Senior Vice President - Nuclear Attachments

1. Westinghouse Electric Corporation Report, N S D-T A P- 1131, entitled

" Responses to NRC Ouestions on the Steam Generator Operating Cycle Evaluation for North Anna Unit 1" (10 Copes)

2. Westinghouse letter, Proprietary Information Withholding Requert cc: U.S. Nuclear Regulatory Commission Region 11 101 Marietta Street, N.W.

Suite 2900 Atlanta, Georgia 30323 Mr. M. S. Lesser NRC Senior Resident inspector North Anna Power Station t