Wednesday, September 8, 2010

Internal BP Report: 'sequence of failures' doomed the Deepwater Horizon

BP has released a 193-page report detailing the company’s own investigation into the causes of the blowout, explosion and fire that killed 11 men and set off the worst marine oil spill in US history.  Not surprisingly, BP blames some of its own people for the disaster, but the company spreads some of the blame around, fingering rig-owner Transocean and Halliburton, the company responsible for the cementing job that many point to as the weakest link in the chain of events.  From the New Orleans Times-Picayune:

In the 193-page report, commissioned by former BP chief executive Tony Hayward and conducted by BP's head of safety and operations Mark Bly, the British oil giant sought to spread some of the blame to its contractors, rig owner Transocean and cementing firm Halliburton.

Bly's report boiled the disaster down to this: The cement that was supposed to line the bottom of the well and keep out hydrocarbons failed; a test of pressure in the well was misinterpreted by BP engineers and Transocean rig workers; the Transocean rig crew took 40 minutes to recognize that gas was kicking up toward the rig; they routed the gas through a goose-neck tube that fed onto the rig, rather than diverting it overboard; ventilation systems allowed gas to get in the engine rooms; and the supposedly fail-safe blowout preventer failed.

Most of these issues have come out in the course of federal investigations. But BP's assessment is much more focused on what rig workers, mostly from Transocean, did after the blowout had already begun, rather than on the decisions BP engineers and others made about the design of the well and various safety measures that are supposed to stop a blowout before it happens.

The Executive Summary of the report identifies eight key findings (PDF) ranging from poor cementing and testing procedures to well control procedures after the emergency had gotten underway.

The report documents what many have already surmised: That the people in charge of the well-capping process—from BP’s office in Houston to the men on the deck of the rig—failed  to follow basic engineering principles and abandoned well-established safety procedures in a series of making the wrong choices before, during and after the blowout.  Engineering textbooks are filled with examples of consequences resulting from poor engineering and safety procedures.  The Deepwater Horizon Incident is surely set to be one of the most oft-cited in the years to come.

The key “take away” from the incident and the investigations’ findings are that the whole of the chain of wrong choices represent an exceedingly rare chain of events.  Had someone made the right choice at any point in the process, the disaster would have likely been averted or brought under control before it morphed into a catastrophe. 

Indeed, the executive summary says almost exactly the same thing:

The team did not identify any single action or inaction that caused this accident. Rather, a complex and interlinked series of mechanical failures, human judgments, engineering design, operational implementation and team interfaces came together to allow the initiation and escalation of the accident.

Multiple companies, work teams and circumstances were involved over time.

Offshore oil and gas exploration has been a very safe activity.  This is the first major blowout and oil spill since the 1979 Ixtoc II spill in the Bay of Campeche.  The reason for that is because safety protocols and engineering procedures are well established and when followed to the letter, they usually result in a safe, predictable event.  But when people think they’re smarter than the textbooks or just don’t believe that things are as bad as they seem, they court disaster.

And on April 20, 2010, disaster is just what they got.  You can follow the events from April 20 through today’s report release at the Deepwater Horizon Incident Timeline at this blog.