BP Plc said the U.S. Coast Guard on Tuesday ended patrols and operations on the final three shoreline miles in Louisiana, bringing to a close the four-year cleanup of the Gulf Coast following the Deepwater Horizon oil spill.

The move completes a cleanup operations that ended in Florida, Alabama and Mississippi last June, BP said in a statement on Tuesday.

The 2010 disaster in the Gulf of Mexico killed 11 rig workers and spilled 4 million barrels of oil in the worst offshore spill in U.S. history.

“BP has spent more than $14 billion and more than 70 million personnel hours on response and cleanup activities,” Laura Folse, BP’s executive vice president for Response and Environmental Restoration, said in a statement.