OAKLAND, Calif. (AP) -- Shell Oil Co. has been ordered to pay $19.5 million to the state for environmental violations at gas stations around California.

The findings come after the Attorney General's Office launched an investigation in 2006 of 1,000 gas stations that found "numerous violations." Many dealt with failure to properly monitor underground storage tanks and spill alarm systems.

Under terms of Friday's judgment, Shell and its related entities will pay $19.5 million in civil and administrative penalties. They also must immediately bring its underground fuel storage into compliance with state laws and implement employee training.

Shell attorneys agreed to the judgment, which was signed Friday in Alameda County Superior Court.