Investigators: Hydraulic leak caused well device to fail
Wed, 12 May 2010 18:00:56 GMT —
WASHINGTON (AP) " A key safety device known as the blowout preventer used in the BP oil rig in the Gulf had a hydraulic leak and other problems that likely prevented it from working as designed, congressional investigators said Wednesday.
They also said BP PLC and other documents also indicated confusion over whether poor pipe integrity was allowing methane gas to leak into the well just hours before the explosion that killed 11 workers and blew the well open.
Rep. Henry Waxman, D-Calif., said that BP had informed his House committee that at some point when the well was being closed with cement an influx of methane entered the wellhead, indicating that cementing the well had not produced needed pipe integrity.
Waxman, opening a hearing into the April 20 well explosion that unleashed a massive oil spill, said while "we have far more questions than answers" it appeared clear " from BP and other documents " that there were problems with the blowout preventers before the accident and confusion almost right up to the time of the explosion over the success of the cementing process.
The committee said that there were at least "four significant problems with the blowout preventer" used on the Deepwater Horizon drill rig.
Rep. Bart Stupak, D-Mich., said that a 2001 report by Transocean, which made the device, indicated there can be as many as 260 failure possibilities in the equipment. The device is supposed to be the final safeguard against a well blowout by clamping down and sealing a gushing oil well.
"How can a device that has 260 failure modes be considered fail-safe?" asked Stupak.
The House Energy and Commerce Committee was to hear from executives of BP, Transocean Ltd, Halliburton, which conducted the cementing on the BP rig, and Cameron Inc.
Stupak said BP confirmed in documents that a leak had been found in the hydraulic system that provides emergency power to a part of the blowout preventer.
When a remote underwater vehicle tried to activate the safety device a loss of hydraulic pressure was detected, said Stupak. When dye was injected "it showed a large leak coming from a loose fitting," said Stupak, citing BP documents.
He said Cameron officials had told the committee the leak was not believed to have been caused by the blowout because other fittings in the system were tight.
Stupak that BP also confirmed that the blowout preventer had been modified so that one of its ram drivers could be used for routine testing and was no longer designed to activate in an emergency. He said after the spill BP "spent a day trying to use this ... useless test ram.
Copyright 2010 The Associated Press.