British Petroleum released the results of its preliminary findings on the cause of the rig explosion that killed 11 people and caused a massive oil spill unlike any other before it. In the report BP stated that “multiple companies and work teams” were at fault for the accident.
Eight reasons were listed in the investigation report beginning with a finger pointed at Halliburton. The number one reason listed for the incident was a defect in the annulus cement barrier that was intended to isolate hydrocarbons. BP claims that if Halliburton who provided the annulus cement barrier design had provided comprehensive lab tests the accident could have been circumvented. They reported that this cement slurry did not isolate the reservoir hydrocarbons because it seems there was too high a percentage of nitrogen that made it difficult to create a stable foam, there were no fluid loss additives in the cement, and a small volume of cement was used in relation to the displacement volume.
The second contributing factor listed stated that the shoe track barrier did not isolate hydrocarbons. BP reports that the Casing was well centralized across the primary hydrocarbon zones though they only used 6 centralizers instead of the standard 21. They go on to report that if there had not been flow up the riser, then the 6 centralizers would have done just fine.
Reasons three, four, five and six point the finger at the Transocean rig crew implying that the crew on board failed to read the signs of trouble. Number three stated the negative pressure test was wrongly accepted though the integrity of the well had not yet been established. Reason number four states that because of this incorrect pressure reading, the influx was not recognized until the hydrocarbons were in the riser. This caused contributing factor number five; the well control response actions failed to regain control of the well. Leading to number six, the hydrocarbons rose through the riser and into the mud gas separator allowing the gas to be vented onto the rig instead of being diverted overboard.
We then arrive at contributing factors seven, and eight. Number seven states the fire and gas system did not prevent the hydrocarbons from igniting and number eight states the BOP or Blowout Preventor emergency system did not shut in the well as it was designed to do. Two systems BP was responisble for.
BP admits that these are only preliminary findings and that not all the evidence has been reviewed but the BP investigators are sure they have drawn the right conclusion. They are not solely at fault for this horrific disaster if at fault at all. After all had everyone else done his job, the emergency system would not have been needed.