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Tuesday, October 23, 2012

SCE repairs hydrogen leak at San Onofre

Below is a press release from Southern California Edison, courtesy Jennifer Manfre.

Southern California Edison Repairs Small Hydrogen Leak

ROSEMEAD, Calif., Oct. 22, 2012 — Southern California Edison (SCE) repaired a small pipe fitting at its shut down 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.

7:40 AM Eastern 10/23/2012


  1. I presume it was a hydrogen supply line to the alternator.
    On our 500MW sets the alternators had very poor seal design and constantly leaked H2 so we always had it trended and had to top them up once a shift.
    One day the hydrogen pressure in the alternator started to fall very rapidly. Operators were urgently dispatched to the field to find the leak only to discover a worker cursing and swearing about the lousy air pressure in the station - he had connected his jack hammer to the alternators purging line and was running it on pure hydrogen. We rapidly changed all the purging fittings after that.

  2. Thanks for these reports!

    All these little non-nuclear events and maintenance issues being reported and "misused" as perils-in-waiting by media and anti-groups is like death by a thousand cuts to nuclear energy's image to an non-discriminating nuclear-sci illiterate public.

    James Greenidge
    Queens NY