San Onofre, CA

3/29/12 San Onofre Power Plant Misled Federal Regulators: Report, Huffington Post

LOS ANGELES — The troubled San Onofre nuclear plant in Southern California will remain shut down while investigators try to solve a mystery inside its massive generators – the rapid decay of tubing that carries radioactive water, federal regulators said Tuesday. The announcement that formalized an agreement with operator Southern California Edison came on the same day that a report commissioned by an environmental group claimed the utility misled the Nuclear Regulatory Commission about design changes that are the likely culprit in excessive tube wear. A four-page letter to Edison from NRC Regional Administrator Elmo E. Collins laid out a series of steps the company must take before restarting the seaside reactors located 45 miles north of San Diego, underscoring the concern over the unusual degradation in the tubes. Read more...

3/27/12 San Onofre nuclear plant closed indefinitely until problems fixed, LA Times

It remains unclear how long the San Onofre nuclear power plant will remain closed after the U.S. Nuclear Regulatory Commission prohibited Southern California Edison from restarting the plant until problems recently discovered are thoroughly understood and fixed.

The plant has already been shut down for two months, the longest in San Onofre's history, after a tube leak in one of the plant's steam generators released a small amount of radioactive steam. Since then, unusual wear has been found on hundreds of tubes that carry radioactive water. Neither regulators nor Edison have said when they believe the plant will reopen. San Onofre supplies about 2,200 megawatts of power, or enough electricity to serve of 1.4 million homes. State officials are already working on contingency plans to avoid power outages during the summer months if the plant remains out of commission.

Until now, the cause of the tube problems has been a mystery. But in a letter federal regulators sent to Edison on Tuesday, officials said tubes were vibrating and rubbing against support structures and against adjacent tubes. Read more...