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Tuesday, November 02, 2010

Controversies: Det Norske Veritas BOP Autopsy & Cement

The Interior Department is planning to pay the Norwegian firm Det Norske Veritas (DNV) $1.3 million to conduct the autopsy of the 60-foot high, 380-ton blow out preventer (BOP) that failed to prevent the Macondo oil and gas well from exploding on April 20. It is controversial because this is the same firm that approved safety procedures for the Deepwater Horizon drilling rig before it exploded and sank in the accident. The BOP is now sitting on a dock at the NASA Michoud assembly plant in Louisiana. A diagnosis of what went wrong with the BOP is key to explaining the explosion that triggered the massive oil spill in the Gulf of Mexico. Future regulations, and possibly billions of dollars of legal liability, are linked to the outcome.

Some believe the firm's earlier work for Transocean, the owner and operator of the Deepwater Horizon, poses a conflict of interest. In 2007, DNV inspected and recertified the Deepwater Horizon's safety procedures. In 2009, Transocean hired DNV to study the reliability of subsea blowout preventers. That same year, DNV named a Transocean vice president, N. Pharr Smith, to be chairman of DNV's rig owners' committee, which provides "input" to DNV's rule-making process.

Hours after a presidential commission raised new questions about the safety of the cement mixture intended to temporarily seal BP's Macondo exploration well, oil field service giant Halliburton reported that the final version of the mixture did not undergo a foam-stability test. The presidential commission investigating the mammoth oil spill found that the cement mixture repeatedly failed lab tests before the April 20 blowout.

According to evidence collected by the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling, Halliburton was getting poor results in lab tests of the recipe for the cement it was planning to use.  Three separate tests suggested that the mixture would be "unstable." The two companies went ahead with the cementing job anyway. Its failure became the first in a cascade of factors leading to the accident. The cement at the bottom of the exploratory well was supposed to have provided a seal until a production facility could be built. The reason for the cement job's failure has been a matter of dispute for months. Halliburton has pointed at BP; BP has challenged Halliburton.

The commission has concluded that the cement was just one contributor to the disaster, noting that cementing wells is a complex endeavor and cementing failures are not uncommon even in the best of circumstances. But the new details call into question whether Halliburton's recipe - which mixed nitrogen and other additives with ordinary cement to create a foamy mixture - was the right one.

At the commission's request, Chevron recently carried out independent lab tests of a cement slurry that Halliburton said was the same as that used in the Macondo well. The commission staff said Chevron reported that "its lab personnel were unable to generate stable foam cement in the laboratory using the materials provided by Halliburton." The commission staff said in the letter Thursday that the Halliburton tests before the Macondo well blowout and the new lab tests conducted by Chevron show that "Halliburton (and perhaps BP) should have considered redesigning the foam slurry before pumping it at the Macondo well.

Many of the earlier explanations of the failure of the cement job in the Macondo well have pointed to BP's decision to use six instead of 21 centralizers, devices that ensure the drill pipe is centered in the hole. Some speculate that the fact that BP and Halliburton knew this cement job could fail only solidifies their liability and responsibility for this disaster. (Wash Post, 11/2/2010, Wash Post, 10/29/2010)

Center Statement Before National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling

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