Image: Screen grab from BP video showing underwater robot working on pipe.
First the Dome, Then the Tube, Then the 'Top Hat', Then the Junk Shot...
BP is trying to insert a tube into the perforated riser pipe to divert some of the leaking oil to a ship on the surface. They're attempting to do this with the biggest leak, which accounts for about 85% of the total oil flowing into the Gulf. As with anything done 5,000 feet under the surface, it's a complicated job that might not succeed. But even if it does, it's still just a partial, temporary fix to the problem, and they're still far from having completed the drilling of the relief well.Top Hat
The 'top hat', a 5-foot collection chamber hooked to a long tube, is being kept in reserve. If the 'intubation' doesn't work, they'll try to deploy it to contain and siphon off the leaking oil (kind of a smaller version of the 100-ton containment dome that they deployed a few days ago, but which failed because of the formation of methane hydrates that clogged the pipe).
Even if all of this fails, the 'junk shot' (trying to clog the riser pipe long enough to be able to plug it with concrete) won't happen for a few more days. Bloomberg writes:
BP is preparing a "junk shot" for the end of next week that would inject tire pieces and golf balls, followed by mud and cement, to plug the leaking well. It also is drilling a relief well that could permanently plug the leak, an effort that began May 2 and will take 90 days to complete.
The junk shot may be ready as early as May 18, U.S. Coast Guard Commandant Thad Allen, the national coordinator for the spill response, said today at a press conference on Dauphin Island, Alabama. (source)
See also: 70,000 Barrels or 5,000? What Did BP Know and When Did They Know It?
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