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BP trial looks at how much oil spilled from well

The effects of the Deepwater Horizon oil spill, caused by an April 20, 2010, well blowout, are still visible in the tar mats and oozing crude oil on marshes in Plaquemines Parish, La.

Gerald Herbert/Associated Press

The effects of the Deepwater Horizon oil spill, caused by an April 20, 2010, well blowout, are still visible in the tar mats and oozing crude oil on marshes in Plaquemines Parish, La.

NEW ORLEANS — BP lied to the US government and withheld information about the amount of oil spilling into the Gulf of Mexico after its well blew out in 2010, attorneys told a judge Monday.

But lawyers for the London-based oil giant denied those accusations and said there was no way to prepare for such a unique blowout a mile below the sea floor. Second-guessing the company’s efforts to cap the well was ‘‘Monday morning quarterbacking at its worst,’’ BP attorney Mike Brock said during opening statements of the second phase of a trial over the spill.

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This part focuses on BP’s response to the disaster and is designed to help US District Judge Carl Barbier determine how much oil spewed into the Gulf.

The government’s estimate is 70 million gallons more than what BP says spilled. Establishing how much oil leaked into the Gulf during BP’s struggle to cap the well will help figure out the penalties the oil company must pay. Billions of dollars are at stake.

The first phase of the trial centered on what caused the blowout.

Brian Barr, an attorney for residents and businesses who claim they were hurt by the spill, said BP failed to prepare for a blowout and compounded the problem by misleading federal officials.

BP had a 600-page oil spill response plan that only included one page on ‘‘source control.’’ It simply called for assembling a team of experts to devise a way to stop a blowout, Barr said.

‘‘BP’s plan was nothing more than a plan to plan,’’ he said.

The April 20, 2010, blowout of BP’s Macondo well 50 miles off the Louisiana coast triggered an explosion that killed 11 workers on the Deepwater Horizon drilling rig and spawned the nation’s worst offshore oil spill. BP used a capping stack to seal the well on July 15, 2010, after other methods failed.

BP maintains its spill preparations complied with every government requirement and met industry standards. But the blowout presented unforeseen challenges, Brock said.

In May 2010, BP tried in vain to use the ‘‘top kill’’ method to stop the flow of oil by pumping mud and other material into the blowout preventer. Plaintiffs’ lawyers claim BP knew the strategy was doomed to fail based on higher flow rate estimates that the company didn’t share with federal officials at the time.

In videotaped testimony shown in court Monday, former energy secretary Steven Chu said BP didn’t provide him with certain data that could have been relevant in evaluating the ‘‘top kill’’ procedure.

‘‘If one knew earlier the amount of flow, things would have been different,’’ Chu said.

A week after the spill started, high-ranking BP official Doug Suttles told Coast Guard Rear Admiral Mary Landry that the company estimated oil was flowing at a rate of 1,000 to 5,000 barrels per day. But the company’s adversaries at the trial say BP’s own internal documents and e-mails show an effort to conceal much higher estimates.

The top kill was among several methods that didn’t work. Other attempts, such as the Cofferdam and the ‘‘top hat,’’ also failed. The terms were obscure industry jargon before the spill but became buzzwords as the company scrambled to find a way to plug the well.

BP insists it was properly prepared to respond to the disaster, but Barr argued the company could have capped the well much sooner if it hadn’t ignored decades of warnings about the risks of a deepwater blowout.

‘‘BP refused to spend any time or money preparing to stop a deepwater blowout at its source,’’ he said.

BP used a capping stack to finally stop the gusher on July 15, 2010. Brock denied that BP could have stopped the spill much sooner if it had a prebuilt capping stack on hand. Nobody in the industry had used such a device before, he added.

Under the Clean Water Act, a polluter can be forced to pay a maximum of either $1,100 or $4,300 per barrel of spilled oil. The higher maximum applies if the company is found grossly negligent, as the government argues BP should be. But the penalties can be assessed at amounts lower than those caps.

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