Carbon-dioxide discharge causes alert at California's Diablo Canyon nuclear power plant

SAN LUIS OBISPO, Calif. (AP) — An accidental discharge of too much carbon dioxide from a fire-suppression system triggered an alert Wednesday at the Diablo Canyon nuclear power plant on California's central coast.

Pacific Gas & Electric spokesman Kory Raftery said everyone at the plant was fine and there was no threat to public safety.

The alert began at 10:56 a.m. and continued through midafternoon. It would be called off when carbon dioxide levels were reduced, Raftery said.

The discharge occurred during a test of the fire suppression system in a room that houses a tank of oil to lubricate the turbine generator for one of the plant's two nuclear units. The "puff" test was being conducted after maintenance on the system.

"More was discharged than anticipated," Raftery said.

An alert, the second level of a four-tier emergency classification system for the twin-reactor plant, must be reported to the Nuclear Regulatory Commission, he said.

The alert means there is an actual or potential degradation of plant safety but it did not involve the nuclear reactors and there was no radiological release, said PG&E spokeswoman Kristin Inman.

Diablo Canyon is on the San Luis Obispo County coast midway between Los Angeles and San Francisco. It has been operating commercially since 1985 and supplies enough electricity to power about 3 million homes in Northern and Central California.