ML20247R122
| ML20247R122 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 05/23/1989 |
| From: | Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20247R128 | List: |
| References | |
| 89-336, NUDOCS 8906070138 | |
| Download: ML20247R122 (2) | |
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n VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 May 23, 1989 4y i
United States Nuclear Regulatory Commission Serial No.89-336 Attentien: Document Control Desk N0/DLDM R5 Washington, D.C.
20555 Docket Nos.
50-338 50-339 License Nos.
NPF-4 NPF-7 Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATfDTWIIT5TIND 2 PROPOSED TECHNICAL SPECIFICATIONS CHANGE Pursuant to 10 CFR 50.90, the. Virginia Electric and Power Company requests amendments, in the form of changes to the Technical Specifications, to Operating License Numbers NPF-4 and NPF-7 for North Anna Power Station Unit I and Unit 2. respectively. These amendments will reduce the Technical Specifications 3/4.2.5 limit on the minimum measured flow rate in the reactorcoolantsystem(RCS) for both North Anna units.
The proposed changes are provided as Attachments 1 and 2.
Both North Anna Units are currently: experiencing RCS flow reductions caused by steam generator tube plugging. As expected, the RCS flow has decreased with increased steam generator tube plugging. Although resolution of the steam generator tube degradation problem is being pursued by both Virginia Electric and Power Company and the industry, lower RCS flow rates due to steam generator tube plugging are expected.
This Technical Specification change will provide margin for the anticipated North Anna units' lower RCS flow rates, while still maintaining operational parameters within the UFSAR analysis envelope.
The proposed Technical Specification change allows a lower total RCS flow by taking credit for previously unused design margin without requiring a L
reanalysis of the Updated Final Safety Analysis Report Chapter 15 accident analyses. The reduced RCS flow rate will be offset by-the conservatism inherent in the existing calculated DNBR design margin. As shown in the Safety Evaluation (Attachment 3), this reduction in DNBR design margin is i
considered acceptable and does not adversely affect the Chapter 15 accident analysis.
The request has been reviewed by the Station Nuclear Safety and Operating of Committee and the Safety Evaluation and Control staff.
It has been go 8906070138 890523 PDR ADOCK 05000338 P-PDC L
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.o determined that.this request does not-involve an Unreviewed Safety Question as defined in 10.CFR 50.59. or a Significant Hazards Consideration as defined:
in' 10 CFR 50.92.: A 10 CFR 50.92~ evaluation:is provided as Attachment 4.
. IfHynu have 'any. questions or require additional;information, please contact L us.
Very truly yours, b
W..L'. Stewart-Senior Vice President
. Power l
Attachments' 1..
Proposed Technical Specifications Changes.for. North Anna Unit 1
. Proposed Technical.' Specifications Changes for North Anna Unit 2-i 2.
- 3. : Safety Evaluation in Support of Reduced Minimum Reactor Coolant ~ System Flow Rate for North' Anna Units 1 and 2 4.: 10 CFR 50.92 Evaluation cc:
U. S. Nuclear Regulatory Commission Region II
'101 Marietta Street N.W.
l l
Suite 2900 Atlanta, Ge'orgia 30323 Mr. J. L. Caldwell
.NRC Senior Resident Inspector North Anna Power Station
-Commissioner Department of Health Room 400 109 Governor Street Richmond, Virginia' 23219 4
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