Prior to Oil Spill, Halliburton Testing Showed Well Cement Was ‘Unstable’
Testing conducted by Halliburton weeks before the Macondo well blowout indicated that the cement to be used to secure the well casing was unstable, staff for the national oil spill commission said today. At the same time, BP had some initial data showing that a cement mixture similar to the one that would be used in the Macondo well was unstable, but did not act on that information.
While BP is legally considered the responsible part for the oil spill, the revelation is certain to raise questions about what role Halliburton played in the disaster and how liable the company should be for the resulting damages.
The cement casing in question, according to an Oct. 28 letter from spill commission staff to the spill commissioners, “should have prevented hydrocarbons from entering the well.” But testing by Halliburton, the company responsible for cementing the well, of the nitrogen foam cement used in the well indicated that the foam was unstable, according to internal Halliburton documents provided to the commission.
Two tests conducted in February 2010, using different parameters than were used in the Macondo well, found that the foam was unstable. Another test, conducted in April using the exact same foam that would be used at the Macondo well, also indicated that the foam was unstable. A fourth test conducted in April found that the foam was stable.
Here are the findings from the letter:
(1) Only one of the four tests discussed above that Halliburton ran on the various slurry designs for the final cement job at the Macondo well indicated that the slurry design would be stable; (2) Halliburton may not have had—and BP did not have—the results of that test before the evening of April 19, meaning that the cement job may have been pumped without any lab results indicating that the foam cement slurry would be stable; (3) Halliburton and BP both had results in March showing that a very similar foam slurry design to the one actually pumped at the Macondo well would be unstable, but neither acted upon that data; and (4) Halliburton (and perhaps BP) should have considered redesigning the foam slurry before pumping it at the Macondo well.
The letter also says that poor cementing may not necessarily be the only reason for the well blowout. “Finally, we want to emphasize that even if our concerns regarding the foam slurry design at Macondo are well founded, the story of the blowout does not turn solely on the quality of the Macondo cement job,” the letter says.
The commission will discuss the new information at a hearing on Nov. 9.