ML20210L448
| ML20210L448 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 02/02/1987 |
| From: | Morgan H SOUTHERN CALIFORNIA EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 8702120412 | |
| Download: ML20210L448 (2) | |
Text
k rnr?
y_wn,.-
Southern California Edison Company SAN ONOFRE NUCLEAR GENERATING STATION P. O. BOX 120 SAN CLEMENTE, CALIFORNIA 92672 H.E. MORGAN TELEPHONE February 2, 1987
'7:4>****aa' erariou u.~4cf a U. S. Nuclear Regulatory Commission Document Control Desk Washington, D. C.
20555 Gentlemen:
Subject:
Docket No. 50-206 Special Report San Onofre Nuclear Generating Station, Unit 1
Reference:
Letter, Kenneth P. Baskin (SCE) to H. R. Denton (USNRC) dated May 19, 1986, " Amendment Application No. 136" The reference provided Proposed Change No. 159 to Appendix A, Technical Specifications to Provisional Operating License No. DPR-13. This proposed amendment adds new Limiting Conditions for Operation, Action and Surveillance Requirements pertaining to Dedicated and Alternate Shutdown Systems, and Emergency Lighting Units. As stated in the reference, San Onofre Unit 1 is being operated in accordance with the Proposed Change.
Pursuant to Sections 3.20 and 3.21 of the Proposed Change, this submittal provides the Special Report for Dedicated Shutdown System (DSD) equipment and 8-hour Emergency Lighting Units being inoperable for greater than 60 days.
On September 28, 1986, during troubleshooting and repair of a DSD battery charger low voltage and ground, the Uninterruptible Power Supply (UPS) inverter static bypass switch indicating light failed to illuminate.
Troubleshooting revealed corrosion in several circuit boards which had resulted in grounded circuits. Due to parts unavailability, the inverter was not returned to service until January 12, 1987. Hourly fire vatch patrols for accessible areas credited for having DSD systems installed, were established in accordance with the Proposed Change and remained in effect until the inverter was returned to service.
O e702120412 870202 s
DR ADOCK 0500 j0
-t Document Control Desk Although the minimum equipment specified in the referenced Amendment Application as being necessary for DSD Operability includes Inverter YV30, further review has determined that the inverter does not provide or support any capability to achieve safe shutdown for any postulated fire. Therefore, SCE intends to revise licensing documents, as appropriate, such that compensatory measures for Inverter YV30 inoperability will not be required.
Additionally, on September 28, 1986, 5 of 26 Control Room 8-hour Emergency Lighting Units failed to illuminate during routine surveillance testing.
Also, on November 11, 1986, two additional Control Room lights failed to illuminate during a routine surveillance.
Troubleshooting and repair of the lights requires erection of temporary scaffolding and removal of adjacent ceiling panels that would impede operators in performing certain evolutions during power operations; the work has therefore been deferred to an available outage of sufficient duration, but no later than the mid cycle outage in April 1987. Equivalent lighting (e.g., flashlights) has been provided in accordance with the Proposed Technical Specification Action Statement and will remain in effect until the Emergency Lighting Units are returned to serv' ice.
If you require any additional information, please so advise.
Sincerely, UEm %"
F. R. Huey (USNRC Senior Resident Inspector, Units 1, 2 and 3) cc:
J. B. Martin, Regional Administrator, NRC Region V Institute of Nuclear Power Operations (INPO)