The National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling said yesterday (October 28) concrete meant to temporarily protect the well repeatedly failed lab tests.

The accident killed 11 people and allowed millions of gallons of oil into the Gulf of Mexico, devastating the regional economy and wildlife.

President Barack Obama, whose popularity plummeted over his handling over the crisis, established the commission to investigate earlier this year.

Its ruling claims US oil giant Halliburton knew before the blast the cement was faulty following lab tests and, although it informed BP, both went ahead with the well regardless.

The panel also asked Chevron to test a similar cement-slurry mixture used on the well, with Halliburton agreeing.

The commission, who were tasked with reporting within six months of being formed said yesterday Chevron’s laboratory personnel were ‘unable’ to generate stable foam cement using the materials Halliburton provided and this therefore ‘suggests that the foam cement used on the Macondo well was unstable’.

A letter published by the commission goes on to state this ‘may have contributed’ to the explosion.

A spokesman for Halliburton said the firm had ‘only recently received’ the report and was ‘continuing to review’ the results.

He said: “Halliburton believes that had BP conducted a cement bond log test, or had BP and others properly interpreted a negative-pressure test, these tests would have revealed any problems with Halliburton’s cement.”

He also reiterated Halliburton ‘had warned BP engineers’ its selection of only six centralisers on the casing string would lead to channeling of the cement in the annulus and the casing shoe track.

He claimed BP made the decision to use only six centralisers though an additional fifteen were sent to the rig prior to running the casing.

BP is yet to comment on the commission’s letter but earlier this week announced it has reached an agreement to sell its recently-acquired interests in four mature producing deepwater oil and gas fields in the Gulf of Mexico to Marubeni Oil and Gas for $650 million.

Luke Walsh

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