State regulators are fining the owner of a derelict barge for spilling oil into the Columbia River during an illegal salvage operation in 2011.

The state Department of Ecology on Monday announced the $405,000 fine against Bret Simpson and his company, Principle Metals LLC. The agency says it found that the spill was caused by Simpson's negligence and that he failed to notify state authorities about the spill.

The spill took 10 months and more than $22 million in federal money to clean up. The derelict barge called the Davy Crockett was a 431-foot-long converted World War II-era ship.

Simpson pleaded guilty in federal court in Tacoma last July for failing to report a discharge of oil and unlawfully discharging oil into the Columbia.

A message left with Simpson's attorney was not immediately returned Monday.