San Onofre’s Restart Halted by Feds

The San Onofre Nuclear Generating System (SONGS) must hold off reopening its two reactors until the company better understands the problems facing the plant’s generators, a federal commission stated Tuesday.

The US Nuclear Regulatory Commission sent a letter to SONGS demanding the cause of January’s rapid shutdown be looked into. Southern California Edison will not be allowed to restart the plant’s operations until the problem is understood and fixed, the letter read.

On January 31, operators promptly shut off the plant’s reactors when they discovered a leak in one of the steam generator’s tubes. The other unit was shut off earlier that month for maintenance.

The cause of the leak has still not been determined. However Tuesday’s letter acknowledged that tubes inside the steam generators were "vibrating and rubbing against adjacent tubes and against support structures inside the steam generators."

The letter sent Tuesday asked for Southern California Edison’s word that the problem would be investigated and fixed. Until that happens, the plant won’t be permitted to restart.

Nuclear power expert Dr. Murray Jennex at SDSU said there was nothing surprising in the NRC letter.

Dr. Jennex says this is what was expected and crews are already working on repairs, so it could potentially restart before the summer heat spikes demand.