ML19326E007
| ML19326E007 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 07/21/1980 |
| From: | Crouse R TOLEDO EDISON CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| 633, TAC-11005, NUDOCS 8007250382 | |
| Download: ML19326E007 (1) | |
Text
TOLEDO Docket No. 50-346
%mm EDISON License No. NPF-3 4c-aac P Cnouse Serial No. 633 dl2""
t419' 259-5221 July 21, 1980 t
Director of Nuclear Reactor Regulation Attention:
Mr. Robert W. Reid, Chief Operating Reactors Branch No. 4 Division of Licensing United States Nuclear Regulatory Commission Washington, D. C.
20555
Dear Mr. Reid:
Condition 2.C.(3)(e) of the Davis-Besse Nuclear Power Station, Unit 1 (DB-1)
Operating License (NPF-3) required the reactor coolant system flow indication to meet the single failure criterion with regard to pressure sensing lines to the flow differential pressure transmitters.
Through discussions with your staff and your letter of March 15, 1979 (log No.
375) an NRC staf f position was transmitted that identified an acceptable method of compliance with a similar license condition on another facility.
Toledo Edison Company is modifying its current reactor coolant system (RCS) flow indi-cation scheme in a siiilar manner and will complete this effort prior to startup following the ct' rent refueling outage.
Specifically the design pro-vides for a tee condition just downstream (approximately 4 inches) of the existing pressure tap root valves for both the high pressure and low pressure sensing taps.
Downstream of these tees each set of redundant lines are roc cJ to two flow transmitters. The redundant sets of sensing lines are routed independently, including a new penetration of the secondary shield wall independent from the existing set.
These new sensing lines are stainless steel and seismically-supported.
Two of the flow transmitters receiving these new sens'?g lines have a minimum separstion of 5 feet from the other two transmitter locations. The electrical circuits to these redundant transmitters are being seismically installed and the channel identity maintained in accordance with the requirements c f the reactor protection system as described in the-DB-1 Final Safety Analysis Report.
Very truly yours, ff WW f00$
s RPC/TJM/dem
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THE TCLECO EDISCN COMPANY EC!SCN PLAZA 300 MADISCN AVENUE TOLEDO, CHIO 43552 80072503 h
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