Final seal of BP oil well to begin ('bottom kill')

[mike r]

Source: Los Angeles Times

Work on the ultimate seal of BP's troubled gulf oil well will begin this weekend, sooner than expected, officials said Friday.

Thad Allen, the federal spill-response chief, indicated earlier this week that the so-called "bottom kill" procedure to plug the well for good might not take place until late September or early October if experts decided engineers must apply a new cement seal on top of the well. The cement job, he said, would serve as "insurance" against any spikes in pressure during the bottom kill, which involves penetrating the original well deep underground and jamming it with mud and concrete.

On Friday, however, Allen said that experts instead have devised a way to install a locking sleeve on a device atop the well that will protect it in the event of pressure spikes. That, Allen said, will obviate the need for the cement seal, and speed the process along.

A BP press statement late Friday said that the company would restart work on the bottom kill this weekend. A relief well has been drilled to within 50 feet of the planned intersection point on the original well; it should take crews about four days to finish boring through the rock. From there, Allen has said, it will take several more days to fill the well with mud and cement, and conduct pressure tests to ensure that the BP well — which spewed a record 4.9 million barrels of oil into the Gulf of Mexico — is closed up for good.

Read more: http://www.latimes.com/news/nationworld/nation/la-na-oil-spill-20100911,0,1431525.story