ML20245C392

Forwards North Anna 1 Cycle 8 Relaxed Power Distribution Control Pattern - Core Surveillance Rept

ML20245C392
Person / Time
Site:	North Anna
Issue date:	06/20/1989
From:	Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20245C394	List: ML20245C392 ML20245C493
References
89-318A, NUDOCS 8906260171
Download: ML20245C392 (2)

Text

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VIRGINIA ELECTRIC AND POWERS COMPANY RicilMOND, VIRGINIA 23261 June 20, 1989 j I

United States Nuclear Regulatory Commission Serial No. 89-318A f Attention: Document Control Desk NO/DLM:jm]

Washington, D.C. 20555 Docket No. 50-338 License No. NPF-4 1

- Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNIT 1 RELOAD INFORMATION- FOR CYCLE 8 North Anna Unit No.1 has completed its seventh cycle of operation and has entered into a refueling outage. We have completed the fuel examination which consisted of 3 ultrasonic testing and visualinspection via binoculars and high magnification TV. As a  !

result of these inspections, two assemblies were identified as having failures creating I the need to modify the design assumptions for Cycle 8. In addition one demonstration assembly was removed from the previously planned cycle design due to difficulties in replacing the removable top nozzle on that assembly. We have developed a revised .

l Cycle 8 reload core design which replaced the above mentioned assemblies with other I

assemblies from our spent fuel pool. The purpose of this letter is to advise you of our revised plans for the Cycle 8 reload core and to transmit to you the revised Core l Surveillance Report containing specific power distribution limits applicable for Cycle 8 l operations.

The Cycle 8 reload core was analyzed in 'accordance with the methodology documented in the approved topical report VEP-FRD-42, Revision 1-A, " Reload Nuclear i Design Methodology," using NRC approved codes as referenced in the topical. The ,

information in the report was developed in accordance with our topical report VEP-NE-  !

1-A, " Relaxed Power Distribution Control Methodology and Associated FQ Surveillance Technical Specifications." These analyses were performed and reviewed by our ,

technical staff. The results of these analyses' indicated that no key analysis parameters would become more limiting during Cycle 8 operation than the values assumed in the currently applicable safety analyses. Further, the analyses demonstrated that the current Technical Specifications are appropriate and require no additional changes.

A review has been performed by both the Station Nuclear Safety and Operating Committee and the Safety Evaluation and Control Staff. It has been determined that no unreviewed safety question as defined in 10 CFR 50.59 will exist as a result of the Cycle 8 reload core.

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, J l Attachment 1 provides the revised Core Surveillance Report containing the specific '

Cycle 8 values for N(Z) and the Axial Flux Difference limits. These limits are based upon the current total peaking factor (Fq) limit of 2.19. Technical Specification 6.9.1.7 .

requires that the report be provided to the NRC 60 days prior to cycle criticality unless a written waiver has been granted by the staff. For the above mentioned reasons we were unable to meet the 60 day requirement. A written waiver was requested in our letter Serial No.89-192 dated April 13,1989 for reasons stated therein. However, these reasons did not include the above stated changes to the cycle design as they were not known to have been required at that time. This letter transmits the Core Surveillance Report for the redesigned Cycle 8 core and replaces the original Cycle 6 Core i Surveillance Report which was previously transmitted by letter Serial No.89-318 dated April 28,1989.

In accordance with Technical Specification 6.9.1.7, your written approval is requested prior to Unit 1 start-up which is currently scheduled for early July 1989. Should you have questions, pleace contact us at your earliest convenience.

Very truly yours, W. L. Stewart Senior Vice President - Power cc: U.S. Nuclear Regulatory Commission Region ll 101 Marietta Street, N.W.

Suite 2900 1 Atlanta, Georgia 30323 1 I

4 Mr. J. L. Caldwell NRC Senior Resident inspector North Anna Power Station

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