BP Oil Spill: As Companies Point Fingers at Each Other, New Concerns About Blowout Preventers

May 12, 2010 — -- The initial phase of a Congressional investigation into the massive oil rig explosion and spill in the Gulf of Mexico uncovered new evidence Wednesday that showed a critical device meant to prevent a disaster had leaks and lacked sufficient force to seal off the well.

"This seemed astounding to us," said Rep. Bart Stupak, a Michigan Democrat who is helping oversee the investigation. "The safety of its entire operations rested on the performance of a leaking, modified and defective blowout preventer."

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"This is supposed to be the last line of defense against a blow out of the well, but it failed," Committee Chairman Henry Waxman (D-Calif.) added as Wednesday's hearing with oil executives got underway.

The new disclosures dealt with the so-called "blowout preventer," a five-story, 900,000-ton device on the sea floor that was supposed to cap the well before a blowout occurred. Its failure, while not the cause of the disaster, could have prevented the blast that killed 11 people and unleashed a flow of oil into the Gulf of Mexico, the industry officials said.

Documents obtained by the committee and presented to the executives Wednesday showed the device had a significant leak in a key hydraulic system. This leak was found in the hydraulic system that provides emergency power to a shear arm that is supposed to cut the drill pipe and seal the well in an emergency. Another internal document released by the committee showed that the blowout preventer was not always powerful enough to cut through the joints in a drill pipe. It only worked 90 percent of the time, the document said.

The oil industry has repeatedly represented to federal regulators that blowout preventers are a key ingredient in what keeps offshore drilling safe. During Wednesday's hearing, they appeared to disagree over which company had responsibility for policing the effectiveness of the safety equipment.