Efforts to stem the Deepwater Horizon oil spill on top of which the new cap was located. The well integrity test was scheduled to take place after the installation of a three-ram capping stack over the lower marine riser package of the Deepwater Horizon semi-submersible rig on . On July 14, BP announced that the test would be delayed under Allen's orders; oil continued to flow into the Gulf. On July 15, 2010, BP announced that it had successfully plugged the oil leak using a tightly fitted cap. The cap, weighing 75 tons and standing high, is now bolted to the failed blowout preventer. It consists of a
Volume and extent of the Deepwater Horizon oil spill in August 2010. USF's David Hollander remarked, "Oil's presence on the ocean floor didn't diminish with time; it grew" and he pointed out, "the layer is distributed very widely," radiating far from the wellhead. In 2013, some scientists at the "Gulf of Mexico Oil Spill and Ecosystem Science Conference" said that as much as one-third of the oil may have been mixed with deep ocean sediments and dragged to the bottom of the ocean floor where it remains, risking damage to ecosystems and commercial fisheries. Oil at or near the site of the spill following well closure has suggested to