"The April 20, 2010, explosion of the Deepwater Horizon offshore drilling rig led to the largest oil spill in U.S. waters. Federal government officials estimated that the deepwater well ultimately released (over 84 days) over 200 million gallons (or 4.9 million barrels) of crude oil. Although decreasing amounts of oil were observed on the ocean surface following the well's containment on July 15, 2010, oil spill response officials and researchers have found oil in other places. A pressing question that has been raised by many stakeholders is where did the oil go? On August 4, 2010, the federal government released an estimate of the oil spill budget for the Deepwater Horizon incident. On November 23, 2010, the federal government released a peerreviewed 'Technical Document' that further explained how the estimates were derived, and in some cases, modified the initial estimates. The oil budget estimates divide the released oil into seven categories, accounting for the following percentages of the total oil released."
CRS Report for Congress, R41531