In the evening of 20 April 2010 disaster struck at the Deepwater Horizon oil rig when a blowout caused by a surge in methane gas from the oil well exploded engulfing the platform. For the next 87 days, BP engineers tried to staunch the flow of crude oil gushing out of the well on the ocean floor. An estimated 184 million gallons were spilt, 18 times the amount spilled by the Exxon Valdez, making it the largest accidental marine oil spill in the world, and the largest environmental disaster in US history.