Friday, September 5, 2014

Your morning longread: a court judgment on the Deepwater Horizon disaster

I know that you've always wanted to understand the physics, chemistry, engineering and operations of deepwater oil drilling and U.S. District Court Judge Carl Barbier is here to help. Here's a 153-page judgment of where exactly the Deepwater Horizon/Gulf oil spill began to go really wrong, including technical diagrams, internal e-mails and even an apportioning of blame. It's obviously too large to summarize well, but here's a couple relevant portions: 
  • On page 53, an interesting chemistry-related discussion of Halliburton defoamer and the decision to pump "foamed cement" into the well. 
  • Beginning around page 70, a very detailed analysis of the decision not to order another "negative pressure test" on the well by the senior B.P. representative on the Horizon, Don Vidrine. (Interestingly, we learn from Judge Barbier that Mr. Vidrine's position on the drilling rig is titled "Company Man.") 
  • Around page 94, the analysis of the failure of the blowout preventer, which included the facts that
    • There was insufficient voltage in a 27 volt battery that operated the blind shear rams, due to not following the manufacturer's recommendation to change out the battery yearly
    • One of the control devices was improperly wired and no tests were performed that would have detected the faulty wiring. 
  • A hilarious bit of e-mail about a spurious explanation/rationalization for an anomalous pressure reading during the negative pressure test (which, if ordered again, could have prevented the disaster): 
289. Five days after the blowout, Well Site Leader Bob Kaluza sent an e-mail to BP personnel that provided a detailed explanation as to how the “bladder effect” could have created the anomalous pressure reading. Patrick O’Byran, BP’s Vice President of Drilling and Completions for the Gulf of Mexico at the time (and who, coincidentally, was on the HORIZON when the explosions occurred), responded to this explanation by typing: 
???????????????????????????????????????????????????????????? . . . 
followed by roughly another 500 question marks. During trial Mr. O’Byran explained, “[A]s I sit here today, I don’t understand what Mr. Kaluza was trying to define, and this [the question-mark-only response] is what we have in front of us today.”
Towards the end, there's an interesting discussion of "gross negligence" and "willful misconduct", followed by the judge's apportionment of blame, which was summarized thusly:
BP’s conduct was reckless. Transocean’s conduct was negligent. Halliburton’s conduct was negligent. Fault is apportioned as follows: 
BP: 67%
Transocean: 30%
Halliburton: 3%
The document is really, really, really technical, but pretty well written and explained. Enjoy? 


  1. Wow. Thanks for posting. That is an extremely well-written document, especially considering the judge isn't a subject matter expert. I'd love to see all safety incidents diagnosed as thoroughly as this one. Given the circumstances, it is amazing there weren't more deaths.

  2. If nothing else, reading this story makes me understand just why petroleum engineers are so well paid.

    1. Civil engineers probably have equal or greater responsibilities, though - for example, the people who designed the Hyatt in KC (see at

  3. If you're really interested in the business politic backstory leading up to those fancy encyclopedia length incident reports, man we need a google chat --- #businessasusual

  4. CJ,

    Hard to believe, but thought it was a real page-turner. The judge was able to write the events up in chronological order, saying why she did or did not believe various testimonies, and why certain failures were and weren't important to the overall disaster. Since the last events were judged the most critical, it really built up like a suspense novel.

    Hollywood is calling for the rights. They've got Clooney, Damon, and JayLo lined up. They want Jeremy Irons for the evil "Company man", but he's playing hard to get...


looks like Blogger doesn't work with anonymous comments from Chrome browsers at the moment - works in Microsoft Edge, or from Chrome with a Blogger account - sorry! CJ 3/21/20