Edison Fined for Safety Mistakes at San Onofre

The U.S. Nuclear Regulatory Commission has proposed that Southern California Edison Co. pay a $150,000 civil penalty for two separate malfunctions in the standby safety systems of the San Onofre nuclear power generating station just south of San Clemente, Edison officials reported Friday.

Neither malfunction posed a hazard to plant workers or the public, according to David M. Barron, an Edison spokesman. But Barron said the utility considers the misalignments to be “serious” problems.

“We don’t intend to contest the notice of violation or the proposed fine,” Barron said, adding that corrective measures, including changes in plant procedures to preclude recurrence, are in place.

An NRC statement released Friday credited the utility with immediate and long-term corrections and praised its “self-critical” and “aggressive” response.

Still, the agency charged the utility more than the base penalty of $50,000 per infraction “because of the duration of the violations.”

The first occurred Aug. 27, 1990, when a water drain valve on a steam supply pipe to a standby feedwater pump on Unit 2 was inadvertently left closed because of an operating error. The valve remained closed until Oct. 21, when the problem was discovered during an unrelated investigation.

The second violation occurred Sept. 24, 1990, when an automatic valve in one of the two, redundant reactor emergency cooling systems at Unit 3 was inadvertently left open for 95 hours--over 12 employee shift changes.