US Investigators: Trapped Piece of Drill Pipe Prevented Sealing of BP Well

WASHINGTON (Dow Jones Newswires), March 23, 2011

A piece of drill pipe trapped inside the Deepwater Horizon's blowout preventer kept the device from averting last year's massive oil spill in the Gulf of Mexico, U.S. investigators said Wednesday.

In the first technical analysis of equipment that the drilling rig leased by BP was using when the rig exploded in April, a forensic report said that a portion of the drill pipe became trapped inside the blowout preventer, a stack of valves on the sea floor that is considered a last resort when operators lose control of a well.

With the pipe buckled and bent, rams design to seal off the well failed to completely sever the pipe, allowing oil to continue surging upward into the ocean, investigators said.

Wednesday's report was drafted by Det Norske Veritas, a Norwegian firm with energy expertise hired to examine the failed blowout preventer. The firm was hired by the U.S. Interior Department and Coast Guard, which are conducting a joint investigation of the spill as the government considers whether to file criminal charges.

The investigation is being watched closely by both the oil industry and U.S. lawmakers, who are considering legislation that would impose new safety requirements on drilling operators. In January, a presidential commission investigating the spill found that BP and other operators made decisions in drilling the well that increased the risk of a blowout, but didn't examine the blowout preventer.

Wednesday's report focused on the mechanical causes of the blowout and didn't assign blame to BP or any of the other contractors involved in operating the rig.

In listing "contributing causes," the report didn't say that the blowout preventer lost power or that it failed to receive signals from the rig, finding instead that shearing rams inside the device fired, but failed to cut off the drill pipe.

The report said the oil industry should re-examine the ability of blowout preventers to function under the conditions that caused the Deepwater Horizon disaster, outlining a list of scenarios that the industry should consider.

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