ML19098B465
| ML19098B465 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 02/27/1976 |
| From: | Stallings C Virginia Electric & Power Co (VEPCO) |
| To: | Reid R, Rusche B Office of Nuclear Reactor Regulation |
| References | |
| Serial No. 912 | |
| Download: ML19098B465 (1) | |
Text
VIRGINIA ELECTRIC AND POWER COMPANY
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Mr. Benard C. Rusche RIOHMOND,VIRGINIA 23261 February 27,
- 1976:
Serial No. 912 PO&M/ALH:clw Director of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D. C.
20555 Docket Nos. 50-280 Attn:
Mr. Robert W. Reid, Chief Operating Reactors Branch 4
Dear Mr. Rusche:
50-281 License Nos. DPR-32 DPR-37 In accordance with Technical Specification 4.14.C.l for Surry Power Station, this report describes an occurrence during which the difference between the river water ambient temperature measured at the station high level intake and cooling water at the discharge control structure exceeded 15 degrees F.
At the time of the occurrence, both Unit Nos. 1 and 2 were operating at 100 per cent power.
On February 15, 1976, at approximately 1610 hours0.0186 days <br />0.447 hours <br />0.00266 weeks <br />6.12605e-4 months <br />, an alarm was received in the main control room indicating that the traveling screen for circulating water pump 1-CW-lD had failed to rotate on its timed cycle.
Investigation revealed that the water screen had jannned and would not rotate in the forward direction.
At 1634 hours0.0189 days <br />0.454 hours <br />0.0027 weeks <br />6.21737e-4 months <br />, circulating water pump 1-CW-lD was shut down to facilitate repair of the screens.
The resulting reduction in circulating water flow caused a gradual increase in temperature difference (t.T) across the station.
To avoid a station t.T in excess of 15 degrees F, a power reduction on Unit No. 2 was initiated at 1718 hours0.0199 days <br />0.477 hours <br />0.00284 weeks <br />6.53699e-4 months <br />.
Despite this re-duction, at approximately 1720 hours0.0199 days <br />0.478 hours <br />0.00284 weeks <br />6.5446e-4 months <br /> the station t.T exceeded 15 degrees F, increasing to a maximum of 15.8 degrees F.
Circulating water pump 1-CW-lD was returned to service at 1727 hours0.02 days <br />0.48 hours <br />0.00286 weeks <br />6.571235e-4 months <br />.
The temperature difference across the station decreased to below 15 degrees Fat approximately 1810 hours0.0209 days <br />0.503 hours <br />0.00299 weeks <br />6.88705e-4 months <br />.
The duration of operation in excess of 15 d.egrees F t.T was approximately 50 minutes.
There was no apparent adverse environmental impact resulting from this occurrence.
Very truly yours, C. M. Stallings Vice President-Power Supply and Production Operations 202?