Another oopsy at San Onofre

San Onofre Nuclear Generating Station suffered yet another accident this weekend when a mechanical failure resulted in the release of 75 gallons of sulfuric acid, according to a spill report (pdf) filed with the U.S. National Response Center. 

The spill was discovered around 2:40 p.m. on Saturday but was not deemed worth reporting to state and federal authorities until Sunday morning at about 9:30 a.m., according to a separate report collected by the California  Emergency Management Agency.

According to the notices, the spill occurred over eight minutes when a piping flange sprung a leak. All 75 gallons of the highly corrosive acid were recovered in secondary containment.

No official comment was immediately available from Southern California Edison, which operates the plant.

This isn't the largest sulfuric-acid spill the plant experienced in recent years. In April 2009, a leak caused 1,000 gallons of sulfuric acid to overflow from a storage tank. In July 2010, two different spills on the same day resulted in the release of 110 gallons of sulfuric acid. In both cases, the acid was allegedly contained. In February 2011, CityBeat reported that San Onofre suffered a 70-gallon spill of another dangerous chemical, hydrazine.

The spill comes a month after hundreds of people turned out for a U.S. Nuclear Regulator Commission hearing, as Patch.com reported, to voice their concerns over the plant's safety record.