Investigators Fault Blowout Preventer in Deepwater Horizon Oil Spill

By Russell Gold 

Federal investigators probing the 2010 Deepwater Horizon disaster say a critical piece of safety equipment may have helped trigger the worst offshore oil spill in U.S. history.

The report by the Chemical Safety Board, an independent investigative arm of the federal government, raises new questions about the effectiveness of blowout preventers, giant sets of valves that are supposed to seal off an oil well in an emergency.

The draft report, set to be released Thursday afternoon, concludes that the pipe running from the subsea oil well to the drilling rig through the blowout preventer, or BOP, buckled shortly after a surge of natural gas from the well ignited, causing an explosion that killed 11 crew members.

The pipe was damaged in such a way that the blowout preventer couldn't cut it and seal it off, the board said. Instead, the blowout preventer punctured the pipe, allowing oil to start flowing into the Gulf of Mexico. The buckling occurred because of big differences in pressure inside and outside the pipe, which ran through about 5,000 feet of water.

This situation wasn't unique to the Deepwater Horizon and could occur at other drilling sites, investigators warned.

(More to come.)

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