A Graphic Look at BP's Top Kill Procedure to Stuff Well

NOLA
Although the "junk shot" has been cancelled -- due to fears that it might make the leak worse -- the "top kill" procedure is planned for sometime in the next week or so. This will involve the rapid pumping of kill mud into the well at high pressure, in the attempt to "stuff" the well, and shut down the flow of hydrocarbons.

With its [siphon tube] containment effort under way, BP is now turning its attention toward permanently shutting down the well responsible for the leaking oil.

Late this week or early in the weekend, BP will perform a "top kill" on the well, Suttles said. That process requires injecting 40 barrels a minute of "kill mud" into the broken well and then sealing it with cement. The material will be pumped at high pressure down the choke and kill lines of the blowout preventer, which failed to seal the well after the rig exploded on April 20, to push the oil back into the reservoir. Choke and kill lines are used to control the amount and pressure of drilling mud in the wellbore, so that surges of oil and natural gas can be kept under control.

BP had initially planned to precede the top kill with a "junk shot," or pumping debris such as golf balls and shredded tires into the blowout preventer to clog the leak, before adding the mud. But Suttles said the company decided not to do the junk shot under concerns that it might cause more damage. BP spokesman Mark Proegler said the junk shot carried certain risks, specifically that the debris could shoot through the well causing more oil to leak.

"If (the top kill) is successful, we would be bringing this incident to a close," Suttles said.

Suttles also said that BP began drilling a second relief well Monday, a back-up to the well that is scheduled for completion in August.

The relief well will permanently intersect with the damaged well and shut it down by pumping concrete into it. Though the relief wells are generally considered to be an effective means of permanently shutting off the well, they are also a more time-consuming option. Drilling relief wells could take months because the drilling process requires frequent starts and stops for safety testing. _NOLA

Again, BP is going with the most cautious approach which might shut down the well fairly quickly -- rather than waiting the 6 to 10 weeks that it will take to get one or both relief wells into position.

Engineers at the BP crisis centre are learning these procedures as they go, since everything when done for the first time at great depth under water, is a new experience.

It is possible that this tragedy will cause the leadership of the US government to wimp out -- like Arnold Schwarzenegger -- and abandon offshore oil and gas drilling entirely. Such a choice would partially handicap US industry, transportation, utilities, and commerce. And certainly many other countries would step in to grab such offshore resources very close to US national waters. Countries such as China, Russia, Cuba, Venezuela, Mexico, Brazil, and so on.

If such countries suffer a similar or worse oil spill accident as Macondo, it is not likely that they will be inviting US government officials to contribute to the mitigation efforts, nor will they be giving interviews to the US Congress or the 60 Minutes news propagram. Nor will they be particularly upset if US fishing or tourism is inconvenienced.

GCC