Bartlit said, "We have known for some time that the cement used to secure the production casing and isolate the hydrocarbon zone at the bottom of the Macondo well must have failed in some manner. That cement should have prevented hydrocarbons from entering the well. For a variety of technical reasons that we will explain at the upcoming hearing, BP cemented the well with a nitrogen foam cement recommended and supplied by Halliburton."
Chevron agreed as a public service to test the cement slurry on behalf of the Commission. Chevron employs some of the industry's most respected cement experts, and it maintains a state-of-the art cement testing facility in Houston, Texas. Halliburton agreed that the Chevron lab was highly qualified for this work. Bartlit writes, "Chevron's report states, among other things, that its lab personnel were unable to generate stable foam cement in the laboratory using the materials provided by Halliburton and available design information regarding the slurry used at the Macondo well. Although laboratory foam stability tests cannot replicate field conditions perfectly, these data strongly suggest that the foam cement used at Macondo was unstable. This may have contributed to the blowout."
Further, Bartlit indicates, ". . .documents provided to us by Halliburton show, among other things, that its personnel conducted at least four foam stability tests relevant to the Macondo cement slurry. The first two tests were conducted in February 2010 using different well design parameters and a slightly different slurry recipe than was finally used. Both tests indicated that this foam slurry design was unstable [emphasis added]. . . on or about April 13, seven days before the blowout. Lab personnel used slightly different lab protocols than they had used in February. Although there are some indications that lab personnel may have conducted this test improperly, it once again indicated that the foam slurry design was unstable [emphasis added]. . .
"Halliburton personnel began a second April foam stability test shortly after receiving the unfavorable results from the first April test. Halliburton personnel again modified the testing procedure, and this time for the first time the data indicated the foam slurry design would be stable [emphasis added].
Based on the testing and documents, Bartlit's legal team concludes:
- (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 hadand BP did not havethe 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 team says, "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. Cementing wells is a complex endeavor and industry experts inform us that cementing failures are not uncommon even in the best of circumstances. Because it may be anticipated that a particular cement job may be faulty, the oil industry has developed tests, such as the negative pressure test and cement evaluation logs, to identify cementing failures. It has also developed methods to remedy deficient cement jobs. BP and/or Transocean personnel misinterpreted or chose not to conduct such tests at the Macondo well."
The Oil Spill Commission and Bartlit have announced they will hold a two-day hearing on November 8-9, on preliminary findings regarding BP's Macondo well blowout. The primary focus of the hearing will be on the causes of the rig explosion. The Commissioners will hear from Chief Counsel Bartlit, representatives from companies involved in the incident, industry executives, technical experts, regulators and others regarding the rig explosion. The hearing will be held at the Grand Hyatt Washington, 1000 H St. NW, Washington, DC.