ML19095A286
| ML19095A286 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 02/14/1978 |
| From: | Stallings C Virginia Electric & Power Co (VEPCO) |
| To: | Case E, Reid R Office of Nuclear Reactor Regulation |
| References | |
| Serial No. 019 | |
| Download: ML19095A286 (2) | |
Text
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Ri:c:HMoNn,V:r:ao:rNIA 23261 February 14, 1978
~Ir. Edson G. Case Acting Director of Nuclear Reactor Regulation United States Nuclear Regulatory Connnission Washington, D.. C.
20555 Attention:
Mr. Robert W. Reid, Chief Operating Reactors Branch 4
Dear. :
- Mr *. Case:
Serial No. 019 PO&M/DLB:das Docket Nos. 50-280 50-281 License Nos. DPR-32 DPR-37 STEAM GENERATOR REPLACEMENT -
SURRY POWER STATION UNIT NOS. 1 AND 2 Due to steam generator tube degradation, the Virginia Electric and Power Com-pany has determined that the replacement of all steam generators for* S~rry Power Station Unit Nos. 1 and 2 will be necessary.
At the time this decision was made, the history of tube failures for both units indicated that an unacceptable unit availability would persist until steam generators could be replaced.
Accordingly, preliminary arrangements were made to replace steam generators on both units at the earliest possible date.
As explained in our submittal of August 17, 1977 en-titled "Steam Generator Pr-0gram, Surry Power Station, Unit Nos. 1 and 2", the pre-liminary schedule included the replacement of Unit 1 steam generators during the period of May through October of 1978 and Unit 2 steam generators during the per-
.. iod February through July 1979.
However, components and materials necessary for steam generator replacement are behind schedule and there may be considerable delays in deliveries beyond the originally scheduled dates. If the preliminary schedule for Unit 1 steam genera-tor replacement is maintained and if component or material delivery delays do oc-cur, the outage would extend accordingly.
In view of this risk, a new steam gen-erator replacement schedule has become necessary.
The new schedule would include the replacement of Unit 2 steam generators during the period October 1978 to May 1979 and Unit 1 steam generators during the period November 1979 to April 1980.
In addition to reducing the risk of outage extension due to delays in deli-veries, the new schedule offers several other advantages.
Concurrent with the development and implementation of an improved steam generator inspection and pre-ventative tube plugging program, the availability of both units has improved con-siderably.
The :µnprovement in availability has provided additional scheduling flexibility and altered the optimal outage scheduling sequence for our nuclear and fossil units.
The new schedule represents an optimal outage sequence based on
, I VIRGINIA ELECTRIC AND POWER COMPANY TO Mr. Edson G. Case Page No. 2 the improved nuclear unit availability.
The new schedule will place both steam generator replacement outages during periods of reduced system demand and eli-minates the need for back to back outages, a potential problem should the first outage extend beyond its scheduled completion date.
Thus, the new schedule reduces the risk of outage extension due to delays in component or materials delivery and optimizes the scheduling of station out-ages.
Steam generator inspection and plugging criteria for continued operation will be consistent with those currently being utilized.
Due to the reduced incidence of tube failures and improved techniques in failure detection.and prevention, the additional operation with.the existing steam generators poses no danger to the health and safety of the general public.
cc:
Mr. Robert W. Reid Very truly yours, C. M. Stallings V.ice President - Power Supply and Production Operations