BP blames the blowout preventer, to halt the blowout once it started. A different account comes from Halliburton, a contractor in the drilling. This account is corroborated to some extent by Transocean, as well as by two workers on the drilling rig, The Wall Street Journal has determined.This account describes a failure to place a cement plug within the well. The plug is designed to prevent gas from escaping up the pipe to the surface.
Well just hold off on that until after the well-completion party!
Before such a plug is placed, the job of keeping underground gas from coming up the pipe is done by heavy drilling fluid inside the well, commonly known as "mud." The plug is normally put in before the mud is removed, but according to the account of Halliburton, Transocean and the two workers, in this case, that wasn't done—drilling mud was removed before a final cement plug was placed in the well.
It is not clear why such a decision would have been made. Rig owner Transocean says that BP, as owner of the well that was just being completed, made key decisions on how to proceed. BP declined to comment on this account of the drilling procedures.
Tim Probert, Halliburton's president of global business lines, plans to testify Tuesday that his company had finished an earlier step, cementing the casing, filling in the area between the pipe and the walls of the well; pressure tests showed the casing had been properly constructed, he will testify.
At this point it is common practice to pour wet cement
"Mud" is at least twice as heavy as seawater and concrete nearly three times as dense. But you have to have a big column of it to hold back the pressure from below.
In this case, a decision was made, shortly before the explosion, to perform the remaining tasks in reverse order, according to the expected Senate testimony of Mr. Probert, the Halliburton executive.
I'm waiting for the Halliburton - Mysterious Conspiracy Division report.