I wish I lived in Norway

[stilltrucking]

BP, the well owner, blames the failure of a big set of valves on the sea floor, known as 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.

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.

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 down into the pipe. The wet cement, which is heavier than the drilling mud, sinks down through the drilling mud and then hardens into a plug thousands of feet down in the well.

The mud then is removed and displaced by seawater; the hardened cement plug holds back any underground gas.

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.

"We understand that the drilling contractor then proceeded to displace the riser with seawater prior to the planned placement of the final cement plug…," Mr. Probert says in the prepared testimony, which was reviewed by The Wall Street Journal. The "riser" is part of the pipe running from the sea floor up to the drilling rig at the surface.

Lloyd Heinze, chairman of the petroleum engineering department at Texas Tech University, agrees that this is an unusual approach. "Normally, you would not evacuate the riser until you were done with the last plug at the sea floor," he said in an interview.

A worker who was on the drilling rig said in an interview that Halliburton was getting ready to set a final cement plug at 8,000 feet below the rig when workers received other instructions. "Usually we set the cement plug at that point and let it set for six hours, then displace the well," said the worker, meaning take out the mud.

According to this worker, BP asked permission from the federal Minerals Management Service to displace the mud before the final plugging operation had begun. The mud in the well weighed 14.3 pounds per gallon; it was displaced by seawater that weighed nearly 50% less. Like BP, the MMS declined to comment on this account.




The Blame Game