Alameda County District Attorney Nancy O'Malley joined state Attorney General Kamala Harris and six other California district attorneys in filing a civil lawsuit Friday against BP West Coast Products, BP Products North America, Inc., and Atlantic Richfield Company for allegedly violating state laws governing hazardous materials and hazardous waste.

The suit claims that the companies failed to properly inspect and maintain underground tanks used to store gasoline for retail sale at more than 780 ARCO gas stations in California.

The complaint filed in Alameda County Superior Court alleges that since October 2006 the BP companies and ARCO have improperly monitored, inspected and maintained underground storage tanks used to store gasoline for retail sale. The complaint alleges that the defendants tampered with or disabled leak detection devices, and failed to test secondary containment systems, conduct monthly inspections, train employees in proper protocol, and maintain operational alarm systems, among other violations.

A statewide investigation found violations of hazardous materials and hazardous waste laws and regulations at gas stations in 37 counties across the state, and at 28 gas stations in Alameda County.