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
Oil spill governance in the United States are co-ordinated by the USCG. The National Oceanic and Atmospheric Administration, Office of Response and Restoration (NOAA) works closely with the USCG in providing assistance in technical areas such as Consideration of Alternatives, Oil displacement tracking and risk assessments. Different authorities are responsible for governing oil spill prevention and anticipation depending on the potential sources of the oil spills. A number of executive orders (EOs) and memoranda of understanding (MOU) have established the authorities and agencies responsible for various classes of potential oil spills (Table 1). Table.1 Federal Agency Jurisdiction for oil spill anticipation and prevention duties, by potential sources.