Southern California Edison Repairs Small Hydrogen Leak

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ROSEMEAD, Calif. (Oct. 22, 2012) — Southern California Edison (SCE) repaired a small pipe fitting at its shutdown San Onofre Nuclear Generating Station after routine maintenance found a small hydrogen leak in the pipe, which is located in the non-nuclear side of the plant.

The leak did not pose a safety risk to workers or the public. The leak was in a Unit 2 pipe fitting near the turbine building.

SCE submitted an event report Sunday to the U.S. Nuclear Regulatory Commission. The utility also notified the California Emergency Management Agency and the San Diego Department of Environmental Health. The repairs were completed by 3 p.m. Monday.

Hydrogen, a flammable gas, is lighter than air, so it rises into the air and dissipates. Given the air flow around the pipe, the hydrogen did not accumulate at unsafe levels.

The pipe maintenance is unrelated to required equipment testing that began last week using a temporary boiler to produce steam in the non-nuclear portions of Unit 2.

Both units of the San Onofre plant are currently safely shut down. Unit 2 was taken out of service Jan. 9 for a planned outage. Unit 3 was safely taken offline Jan. 31 after station operators detected a leak in a steam generator tube.

For updates, please visit www.SONGScommunity.com, or follow us on Twitter at www.twitter.com/SCE_SONGS, and on www.facebook.com/sce. The San Onofre plant is jointly owned by SCE (78.21 percent), San Diego Gas & Electric (20 percent) and the city of Riverside (1.79 percent).

About Southern California Edison
An Edison International (NYSE:EIX) company, Southern California Edison is one of the nation's largest electric utilities, serving a population of nearly 14 million via 4.9 million customer accounts in a 50,000-square-mile service area within Central, Coastal and Southern California.

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Southern California Edison Repairs Small Hydrogen Leak