Environmental impact of the Deepwater Horizon oil spill Environmental impact of the Deepwater Horizon oil spill The 2010 "Deepwater Horizon" oil spill in the Gulf of Mexico has been described as the worst environmental disaster in the United States, releasing about of crude oil making it the largest marine oil spill. Both the spill and the cleanup efforts had effects on the environment. The oil spill was called the "worst environmental disaster the US has faced" by White House energy adviser Carol Browner. The spill was by far the largest in US history, almost 20 times greater than the usual estimate of the Exxon Valdez oil spill. Factors
Volume and extent of the Deepwater Horizon oil spill silts and sands onshore. On 26 May 2011, the Louisiana Department of Environmental Quality extended the state of emergency related to the spill. In April 2012, oil was found dotting of Louisiana's coast. As of December 2012, of coastline remain subject to evaluation and/or cleanup operations. On 15 May 2010, researchers from the National Institute for Undersea Science and Technology, aboard the research vessel "RV Pelican", identified oil plumes in the deep waters of the Gulf of Mexico, including one as large as long, wide and thick in spots. The shallowest oil plume the group detected was at about ,