ML13308B467
| ML13308B467 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 05/11/1977 |
| From: | Head J SOUTHERN CALIFORNIA EDISON CO. |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| NUDOCS 8103060031 | |
| Download: ML13308B467 (3) | |
Text
Southern California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE J.T.
HEAD, JR.
ROSEMEAD, CALIFORNIA 91770 TELEPHONE VICE PRESIDENT May 11, 1977 213-572-1472 Mr. R. H. Engelken, Director Region V U.S. Nuclear Regulatory Commission Office of Inspection and Enforcement Walnut Creek Plaza, Suite 202 1990 North California Boulevard Walnut Creek, California 94595
Dear Mr. Engelken:
Docket No. 50-206 San Onofre Unit 1 An occurrence defined in the Environmental Technical Specifications (Section 5.6.3.b. (3) (a)) as reportable was determined to have happened at the San Onofre Nuclear Generating Station Unit 1 on April 21, 1977. The purpose of this letter is to report the details of that occurrence.
Specification 3.1.1.a. (5) of Appendix B to the San Onofre Unit 1 Provisional Operating License establishes, in part, that proper system operation of the two offshore continuous water temperature recording systems be verified once every two weeks. Each of the two temporary continuous temperature record ing systems consists of sensing devices that record water temperature near the sea surface, midwater, and near the bottom.
During a scheduled operation verification check on April 21, it was discovered that one temperature sensor had been lost during the previous two weeks resulting in a two-week period of missing data. The sensor was at the Zone 6.system's near-surface location.
The lost sensor was replaced when discovered. The other five sensors were also checked at that time and found to be operating properly.
MAYf lU ENFOC
/1&
4SCE Since the sensor could not be located in the vicinity of the buoy and no unusual surf activity had occurred, the loss of this sensor may be the result of an act of vandalism. The hardware attaching the sensors to the anchor chain will be improved. This corrective action will be completed by June 15, 1977.
Very truly yours, cc: Director, Divison of Reactor Licensing Director, Office of Inspection & Enforcement (20)
Director, Office of Management Information & Program Control (2)
10 Kr 2C