Media Contact: (626) 302-2255

ROSEMEAD, Calif., November 1, 2011 — At 6:07 pm PDT, Southern California Edison (SCE) exited the alert declared today following an ammonia leak at the San Onofre Nuclear Generating Station and is transitioning from emergency operations back to normal operations.

Access to all areas of the plant has been restored. SCE is currently evaluating the cause of the incident and taking appropriate corrective actions.

The leak, in the non-nuclear section of the plant, has been stopped and contained. The approximately 25 gallons of leaked ammonia was collected in a basin underneath the tank that was designed for that purpose.

No radioactive material was released and there was no danger to the public.

SCE declared the alert at approximately 3 p.m. PDT based on identifying the ammonia leak in Unit 3’s water purification system. The alert was required because fumes could prevent access to certain areas of the plant.  The control room remained staffed and fully operational, and both Units have been operating safely.

No injuries were reported at the plant. As a precaution, the company evacuated employees in the area near where the leak was found.  Other employees remain in other areas of the plant.

An alert is the second lowest of four federal classifications for emergencies at commercial nuclear power plants. An alert is characterized by events that are in process or have occurred that involve an actual or potential impact on the level of safety of the plant.

SCE and offsite agencies are closing the San Onofre Joint Information Center in Irvine.  News media can contact SCE’s 24-hour media number for further information.

Background Information

  • Nuclear plant emergency classifications are established by the Nuclear Regulatory Commission.
  • The San Onofre plant, located just south of San Clemente, Calif., consists of two pressurized water reactors, Units 2 and 3, similar in design to 69 of the 104 operating U.S. reactors.
  • San Onofre is jointly owned by SCE (78.21%), San Diego Gas & Electric (20%), and the City of Riverside (1.79%).

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.


Alert Ended at San Onofre Nuclear Generating Station