WASHINGTON — Bad wiring and a leak in what's supposed to be a "blowout preventer." Sealing problems that may have allowed a methane eruption. Even a dead battery, of all things.
New disclosures Wednesday revealed a complex cascade of deep-sea equipment failures and procedural problems in the oil rig explosion and massive spill that is still fouling the waters of the Gulf of Mexico and threatening industries and wildlife near the coast and on shore.
The BP well, drilled 18,000 feet below the sea floor, may have failed two critical pressure tests in the hours before its April 20 blowout, according to testimony from executives and interviews with company officials, along with more than 100,000 pages of documents.
And the blowout preventer, designed to contain the gas that ignited the rig fire, had a leak in a crucial hydraulic system as well as a defectively configured ram, its manufacturer testified.
As oil and dead birds washed onto Louisiana shores, the grilling of executives from BP America, Transocean, Halliburton and Cameron marked the second day of congressional scrutiny.
Members of the House Energy and Commerce Oversight and Investigations Subcommittee homed in on the cementing of the well and on modifications to the blowout preventer.
Who ordered the alterations in the 500,000 pound mass of gears and hydraulic valves that sits atop an underwater well and is intended to snap the pipe if disaster threatens, was the subject of dispute at Wednesday's hearing.
Transocean, the owner of the blowout protector and of the sunken Deepwater Horizon rig, said any alterations would have come at BP's instigation; BP, which owns the well and hired Transocean to drill it, said it had never sought the changes.
Traditional industry allies were among the companies' harshest critics. Rep. Joe Barton, R-Texas, said that documents show that there was "in all probability shoddy maintenance," as well as "mislabeled components" and "diagrams (that) didn't depict the actual equipment" used in the operation.
The White House asked Congress to provide $118 million in aid to the Gulf Coast, eventually to be recovered from BP. It also proposed legislation to raise the $75 million cap on oil companies' liability for damages, retroactively, and hike the per-barrel tax that funds a cleanup fund.
"The federal government will not relent in pursuing full compensation," said Carol Browner, assistant on energy to the president. "We take BP at their word. They say they intend to pay for all costs. And when we hear 'all,' we take it to mean all."
As efforts to pinpoint the cause of the accident intensified, BP continued to assess ways to plug the leak, which is spewing 210,000 gallons of oil into the gulf daily. The company lowered a second containment box known as a "top hat" onto the sea floor late Tuesday, but it is also considering whether to insert a tube into the piping instead. The tube would be ready to deploy late today or early Friday.
A third so-called "junk shot procedure," in which shredded tires, golf balls and other material would be pumped into the leak, could be available late next week, according to the company.
Rep. Edward J. Markey, D-Mass., ridiculed the company's efforts, saying that BP is "largely making it up as they go. . . . When we heard the best minds were on the case, we expected MIT and not the PGA," he added.
A senior BP executive, Lamar McKay, cautioned, "It's inappropriate to draw any conclusions before all the facts are known." But the documents established the firmest evidence to date of the sequence of catastrophic events that led to the explosion and worsening spill, a series of failures more reminiscent of the loss of the space shuttle Challenger than the wreck of the Exxon Valdez.
Like the 1986 Challenger disaster, the investigation into the gulf spill may well show that complex and seemingly failproof technical systems went wrong because of overlooked problems that interacted with each other in unexpected ways.
The Obama administration said it had recruited five government and private scientists to add what Energy Secretary Stephen Chu called "intellectual horsepower" to BP's efforts to shut off the well.
Chu, a Nobel laureate in physics, said he was guardedly optimistic. "I'm feeling more confident than I was a week ago. Things are looking up." But he also added that "this is a complicated affair" and said he did not want to be seen as offering false hope.
Information from the Associated Press, Los Angeles Times and McClatchy Newspapers was used in this report.