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
Montara oil spill 1 November. The West Triton jackup drilling rig arrived at the Montara Field in an attempt to plug the oil leak on 11 September 2009. Oil and gas producer, Woodside Petroleum Ltd offered to assist PTTEPAA in cleaning up the oil spill with the use of a rig closer to the spill site. However, PTTEPAA rejected the Woodside offer on the basis of "safety reasons". The Woodside rig was a semisubmersible drilling rig and, as it floats on the sea surface, was not deemed as a suitable platform for the relief well. A jackup rig was required because it could