ML19095A429
| ML19095A429 | |
| Person / Time | |
|---|---|
| Site: | Surry, North Anna  |
| Issue date: | 03/22/1978 |
| From: | Stallings C Virginia Electric & Power Co (VEPCO) |
| To: | O'Reilly J NRC/RGN-II |
| References | |
| IEB-78-004, Serial No. 115B/0222178 | |
| Download: ML19095A429 (2) | |
Text
VIRGINIA ELECTRIC AND POWER COMPANY R:rCHMOND,VIROI:NIA 23261 March 22, 1978 Mr. James P. O'Reilly, Director Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission Region II - Suite 818 230 Peachtree Street, Northwest Atlanta, Geo~gia 30303
Dear Mr. O'Reilly:
Serial No. 115B/022178 PO&M/DLB :_dgt Docket No ~-280 50-281 50-3 License Nos. DPR-32 DPR-37 NPF-4 This is in response to IE Bulletin 78-04, "Environmental Qualification of Certain Stem Mounted Limit Switches Inside Reactor Containment".
Following is the information requested for Surry Power Station, Unit Nos. 1 and 2 and North Anna Power Station, Unit No, 1.
Surry Power Station, Unit Nos. 1 and 2 A document review has been performed in an effort to determine whether NAMCO Model D2400X or EA-170-302 SNAP LOCK switches are installed in safety-related equipment at Surry Power Station.
However, the documentation available does not appear sufficient to determine in all cases, whether any of the subject limit switches are assoicated with safety-related valves.
Therefore, at.the next scheduled outage of each unit, a verification program will be conducted.
The re-sults of the survey and corrective action, if required, will be forwarded to you upon completion.
Based on the current outage schedule, this information will be forwarded on or about July 15, 1978.
North Anna Power Station; Unit No. 1 As stated in IE Bulletin 78-04, and as explained in our letter of November 4, 1977, we have conducted a review at North Anna and have implemented corrective actions.
VIRGINIA ELECTRIC AND POWER CoM. TO Mr. James P. O'Reilly Page 2 As a result of our study, it was determined that the best solution was to alter the circuit of 21 valves in the containment to eliminate the limit switches as the "latch in" device; the "latch in" function to be provided by qualified re-lays located outside the containment.
This approach eliminates the concern of in-containment environmental qualification.
The necessary modifications were com-pleted on Unit 1 as of November 4, 1977.
Very truly yours, ZP. ???. Ji~;#7'~/
C.. M. Stallings Vice President-Power Supply and Production Operations cc:
U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement Division of Reactor Operations Inspection Washington, D. C. 20555