ML071350638
| ML071350638 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 05/14/2007 |
| From: | Gerald Bichof Virginia Electric & Power Co (VEPCO) |
| To: | Document Control Desk, NRC/NRR/ADRO |
| References | |
| 07-0109B | |
| Download: ML071350638 (3) | |
Text
VIRGINIA ELECTRIC AND POWER COMPANY
- RICHMOND, VIRGINIA 23261 May 14, 2007 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 Serial No.
07-01 09B SPS-LICICGL R1' Docket Nos.
50-280 50-281 License Nos. DPR-32 DPR-37 VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 PROPOSED TECHNICAL SPECIFICATIONS CHANGE TEMPORARY 45-DAY AND 14-DAY ALLOWED OUTAGE TIMES TO REPLACE MAlN CONTROL ROOM AND EMERGENCY SWITCHGEAR ROOM AIR CONDITIONING SYSTEM CHILLED WATER PIPING ADDITIONAL INFORMATION REGARDING MAlN CONTROL ROOM HEATUP By letter dated April 5, 2007 (Serial No. 07-0109A), Virginia Electric and Power Company (Dominion) responded to an NRC; request for additional information (RAI).
The RAI response was related to an amendrnent request to Facility Operating License Numbers DPR-32 and DPR-37 for Surry Power Station Units 1 and 2 transmitted to the NRC on February 26, 2007 (Serial No. 07-0109) that will permit the use of temporary 45-day and 14-day allowed outage times (AOTs) to facilitate replacement of Main Control Room (MCR) and Emergency Switchgear Room (ESGR) Air Conditioning System (ACS) chilled water piping.
In the discussion of the Capability of the Elackup Cooling Supply, the April 5, 2007 transmittal indicated that a preliminary MCR heatup calculation was being finalized.
The transmittal also indicated that the preliminary calculation supported the expectation that the MCR temperatures resulting from a loss of chilled water event would remain within design limits for safety related equipment. The April 5, 2007 transmittal identified a commitment to provide verification of the expected MCR heatup results to the NRC by May 18, 2007. The purpose of this letter is to provide that verification.
The MCR heatup calculation was perfornied using GOTHIC, a thermal-hydraulic computer program that is well-suited for roorn heatup analyses. The model developed for evaluation of MCR heatup assumed loss of chilled water flow to the operating chilled water loop with no compensatory measures taken in the MCR (e.g., no doors were opened). The MCR heatup calculation used space heat loads representative of normal
Serial No. 07-01 09B Docket Nos. 50-280, 50-281 Page 2 of 3 operation and summer ambient conditions, which are bounding for the MCR. The results of these calculations confirm that MCR temperatures are within the design limits for the safety-related equipment housed within the MCR.
If you have any questions or require additional information, please contact Mr. Gary D. Miller at (804) 273-2771.
Very truly yours, Gerald T. Bischof w
Vice President - Nuclear Engineering Commitments made in this letter: None.
cc: U.S. Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW Suite 23 T85 Atlanta, Georgia 30303 Mr. D. C. Arnett NRC Resident Inspector Surry Power Station Commissioner Bureau of Radiological Health 1500 East Main Street Suite 240 Richmond, Virginia 2321 8 Mr. S. P. Lingam NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North 1 1555 Rockville Pike Mail Stop 8G9A Rockville, Maryland 20852
Serial No. 07-01 09B Docket Nos. 50-280, 50-281 Page 3 of 3 COMMONWEALTH OF VIRGINIA 1
)
COUNTY OF HENRICO 1
The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Gerald T. Bischof, who is Vice President - Nuclear Engineering, of Virginia Electric and Power Company. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of that Company, and that the statements in the document are true to the best of his knowledge and belief.
Acknowledged before me the day of Y)? A
' 2007' My Commission Expires:
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~ o t a r y Public (SEAL)