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
Ixtoc I oil spill or littoral communities, which were not the subject of this study. Ixtoc I oil spill Ixtoc I was an exploratory oil well being drilled by the semi-submersible drilling rig "Sedco 135" in the Bay of Campeche of the Gulf of Mexico, about northwest of Ciudad del Carmen, Campeche in waters deep. On 3 June 1979, the well suffered a blowout resulting in one of the largest oil spills in history. Mexico's state-owned oil company Pemex (Petróleos Mexicanos) was drilling a deep oil well when the drilling rig "Sedco 135" lost drilling mud circulation. In modern rotary drilling, mud is circulated