ML20046D155
| ML20046D155 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 08/10/1993 |
| From: | Bowling M VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20046D156 | List: |
| References | |
| 93-505, NUDOCS 9308160221 | |
| Download: ML20046D155 (2) | |
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YIRGINIA ELECTRIC AND Powna Comwxy RicutMoxD, VIRGINIA 232GI August 10, 1993 U.S. Nuclear Regulatory Commission Serial No.93-505 Attention: Document Control Desk JDH R2 Washington, D.C. 20555 Docket Nos.
50-338-50-339 License Nos. NPF-4 N PF Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 & 2 SUPPLEMENTAL INFORMATION ON THE RETRAN NSSS MODEL Virginia Electric and Power Company uses the RETRAN transient thermal-hydraulics computer code to perform non-LOCA system transient analyses for North Anna Power Station. Use of this code and its associated station model was originally approved by NRC on April 11,1985, when NRC issued its Acceptance for Referencing of Licensing -
Topical Report VEP-FRD-41-A, " Virginia Power Reactor System Transient Analyses Using the RETRAN Computer Code." As stated in the NRC's Safety Evaluation Report supporting that acceptance, NRC required that future modifications of the model, and-the associated error reporting and change control models, be placed under full quality assurance procedures.
An updated model has been developed and qualified in accordance-with those
~
requirements. The attached report, provided for your information, describes both the updates to the model and the model's qualification process. ' The qualification process was equivalent, in scope and rigor, to that of the original model.. Implementation of the updated model involves no change to the approved core reload design methodology.
(described in the NRC-approved Licensing Topical Report VEP-FRD-42-A), or in the accident analysis basis assumptions supporting the transient analyses described in North Anna UFSAR Chapter 15.
The' updated model has been reviewed and. approved by the Station Nuclear Safety-and Operating Committee and has been determined'not to involve an unreviewed '
safety question or a technical specification change. Therefore, the updated model'is_-
being implemented under the provisions of 10CFR50.59.
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if you have any questions, or require additionalinformation, please contact us.
Very truly yours, M. L Bowling, Manager Nuclear Licensing and Programs Attachment cc:
U.S. Nuclear Regulatory Commission Region 11 101 Marietta Street, N.W.
Suite 2900 Atlanta, Georgia 30323 l
NRC Senior Resident inspector North Anna Power Station
,