Volume and extent of the Deepwater Horizon oil spill Volume and extent of the Deepwater Horizon oil spill The "Deepwater Horizon" oil spill was discovered on the afternoon of 22 April 2010 when a large oil slick began to spread at the former rig site. According to the Flow Rate Technical Group, the leak amounted to about of oil, exceeding the 1989 "Exxon Valdez" oil spill as the largest ever to originate in U.S.-controlled waters and the 1979 Ixtoc I oil spill as the largest spill in the Gulf of Mexico. BP has challenged this calculation saying that it is overestimated as it includes over of oil which was
Exxon Valdez oil spill responsible" for the spill, because they had granted mariners' licenses to the crew of the Valdez, and because they had given the "Valdez" permission to leave regular shipping lanes to avoid ice. They also reiterated the claim that the Coast Guard had delayed cleanup by refusing to give permission to immediately use chemical dispersants on the spill. The Oil Spill Recovery Institute was formed after United States Congress approved it to seek a solution. Collaborating with InnoCentive they found a partial solution for the flow of oil. A report by the US National Response Team summarized the event and made