Buzbee Clients Provide Testimony to MMS and USCG Joint Investigative Panel
During the fifth day of hearings in Kenner on what went wrong April 20 on the Deepwater Horizon oil rig, the size of a final tube of metal casing that was added late to the well design emerged Friday as one of the key management decisions that could have contributed to the rig's explosion and the largest oil spill in U.S. history.
The long and technical hearings by a six-member joint investigative panel of the Coast Guard and Minerals Management Service have exposed disputes among the various companies whose employees played a role on the rig. BP owned the well but leased the rig from Transocean, which provided most of the rig workers. Halliburton was hired to place cement seals in the well, M-I SWACO provided drilling mud, Schlumberger had a team on the rig to run tests and other companies provided key pieces of equipment.
Jason Mathews of the Minerals Management Service, a member of the panel, raised the issue of whether it would have been safer to use a 5-inch production casing in the bottom of the well, where the 13,000-foot-long hole is 8 1/2 inches in diameter and dips into a zone of oil and natural gas.
Christopher Haire, one of the Halliburton cementers, agreed that a 5-inch casing would have been safer. Instead, BP changed the well plan just days before the accident to insert a tube that tapered from 9 7/8 inches down to 7 inches in diameter.
That gave less than 3/4 of an inch on each side for the cement poured the night before the accident to create a solid barrier between the well hole and the earth surrounding it.
The smaller casing would have given the cement at the bottom of the well more room to set and form a bond.
As the investigative panel questioned the man who designed the well, BP drilling engineer Mark Hafle, John McCarroll of the MMS made clear he thought cement failures allowed the well to flow.
"Don't you think for that size casing, you set up your Halliburton cementer for failure, especially when you had a loss return zone (where drilling mud was seeping into the earth) below the hole?" McCarroll asked.
"I believe it's a sound engineering practice," said Hafle, who bristled at some of the questions about the well design and the choice of a new, foamy nitrogen-infused cement.
"Personally, I would not want to try to attempt that," McCarroll responded.
The exchange grew testier before McCarroll backed off.
Hafle also testified that the production casing was not attached to other, larger metal tubes farther up the well, confirming what some drilling experts noticed about well schematics supplied to congressional committees.
Last week, two experts told The Times-Picayune the absence of a sealing attachment would have given gas an open channel to build up pressure all the way up to the well head.
The well head is a device built by Dril-Quip that seals off the top of the hole and connects to the 450-ton blowout preventer; its valves and shearing rams are the last line of defense against a well blowout.
Because tests showed nothing was flowing in the well a few hours before the accident and it was on the verge of being closed up, workers were caught completely off-guard by the blowout. If gas got up the open channel, it could have built up below the well head and blasted through seals suddenly, drilling engineers have said.
Ned Kohnke, an attorney for rig owner Transocean, focused on BP's decision not to run a key cement integrity test called a cement bond log. It is considered by engineers to be the "gold standard" of testing cement jobs.
During his cross-examination, Kohnke told Hafle that The Times-Picayune had reported that BP sent a team of testers home before performing that test. At first, Hafle said he didn't think that was true, but when Kohnke persisted, Hafle said he wasn't aware of it. A spokesman for the company hired to perform the test if BP wanted it, Schlumberger, said last week that it had a crew on stand-by on the rig, but BP sent the team home on April 20 without ordering the cement bond log.
When asked why no cement bond log was conducted, Hafle first said it was because "we had not gotten that far in the well plan when the (blowout) occurred." But later he said there was no plan to conduct the test and the crew was about to close off the well with a final plug, which would prevent any cement bond log tests until the well was reopened some time in the future.
Kohnke asked Hafle what could have gone wrong if it wasn't BP's cement design, but Hafle said he wouldn't speculate.
"I don't believe you'll ever find out how the hydrocarbons got in the well bore," he said.
New Orleans Times-Picayune
May 28, 2010