Processing Magazine

BP Plugs Well With Mud

August 4, 2010
BP claimed a key victory in the effort to plug its blown-out well and the government said much of the spilled oil is gone, reports the Associated Press. BP PLC reached what it called a significant milestone overnight when mud that was forced down the well held back the flow of crude. Also, White House energy adviser Carol Browner said on morning TV talk shows that a new assessment found that about 75 percent of the oil has either been captured, burned off, evaporated or broken down in the Gulf. The next step would be deciding whether to cement the well. The pressure in the well dropped quickly in the first 90 minutes of the static kill procedure, a sign that everything was going as planned, wellsite leader Bobby Bolton told The Associated Press. The static kill involved slowly pumping the mud from a ship down lines running to the top of the ruptured well a mile below. BP has said that may be enough by itself to seal the well. But the mud that was forced down the broken wellhead to permanently plug the gusher is only half the story. To call the mission a success, crews working on a flotilla of vessels on a desolate patch of water need to seal off the well from two directions. An 18,000-foot relief well BP has been drilling for the past three months will be used later this month to execute a "bottom kill," in which mud and cement will be injected into the bedrock 2 1/2 miles below the sea floor to finish the job, retired Coast Guard Adm. Thad Allen said. A 75-ton cap placed on the well in July has been keeping the oil bottled up inside over the past three weeks, but is considered only a temporary measure. BP and the Coast Guard want to plug up the hole with a column of heavy drilling mud and cement to seal it off more securely. BP won''t know for certain whether the static kill has succeeded until engineers can use the soon-to-be-completed relief well to check their work.