BP fights fed’s oil spill estimates in court

NEW ORLEANS – Attorneys for BP and the Justice Department squared off in federal court Monday over how much oil ended up in the Gulf of Mexico in 2010, a pivotal dispute in the trial over the worst oil spill in U.S. history.

Fines for the British oil giant could balloon to $18 billion if U.S. District Judge Carl Barbier agrees with Justice Department calculations on the amount of oil that flowed into the Gulf after the April 20, 2010 disaster on the Deepwater Horizon rig, which killed 11 people.

Four experts, using different methodologies and data BP provided, estimated that 5 million barrels of oil pushed out of the blown out Macondo well, and 4.2 million barrels reached the ocean, said Steve O’Rourke, a Justice Department attorney, in opening statements Monday.

The government and BP have agreed that various containment devices captured about 800,000 barrels of crude before it reached the Gulf.

Government  experts based their calculation  on estimates that crude spewed from the well at a daily rate of about 62,000 barrels  shortly after the blowout, and at  53,000 barrels per day around the time the well was capped on July 15, 2010, O’Rourke said.

He told the court that BP has changed many of its initial assumptions in forming an idea of how much oil spilled in the Gulf, cherry picking data points and effectively lowering the estimate.

An attorney for the British oil giant swung hard at the government’s calculation, saying officials merely extrapolated the data collected from a pressure gauge on the day the well was capped and ignored flow changes over the life of the well.

“They assumed there were no changes in the well during this entire period of time,” Mike Brock, an attorney for BP, said in opening statements Monday.

One model the government used assumed no erosion to BP’s blowout preventer on the well. Brock said a video he showed the court demonstrates that the device had at least three punctures forming weeks after the explosion.

Based on lower flow-rate estimates, BP contends 3.2 million barrels of oil escaped the well, and 2.45 million reached the Gulf. Under the Clean Water Act, BP could be fined between $1,100 to $4,300 per barrel, depending on whether the court rules the company was negligent or grossly negligent. The court also could set the fines lower, and the maximum penalty under BP’s math would be about $10.5 billion.

O’Rourke said BP has disavowed data it collected when it capped the well, and has strategically changed several of its assumptions to find a lower number for the well’s oil “production.” Initially, in 2010, BP’s in-house engineers had estimated the well’s daily oil flow to be in line with the government’s current estimates, O’Rourke said.

But BP’s attorney said the company has now accounted for many factors the government ignored, including erosion in the well, cement tests and examinations of equipment that was retrieved after the well was capped.

In April, Judge Barbier heard arguments apportioning blame for the spill between BP and its contractors for the Deepwater Horizon rig, which sank to the bottom of the Gulf a few days after the explosion that rocked oil production in the region.

Last week, BP and attorneys for spill victims, U.S. officials and BP contractors argued over the company’s efforts to control the blown out well between April 20, 2010 and July 15, 2010, when the Macondo was finally curbed with a capping stack.

Attorneys said on Monday that BP and government experts disagree on the numbers for every input used in calculating how much oil flowed out of Macondo – the well’s drop in pressure over time, the porousness of the rock surrounding well and the volume of oil connected to the well.

Federal officials believe the Macondo’s pressure dropped off over time as the amount of oil in the reservoir depleted, while BP argues the pressure climbed as metals eroded at the wellhead. That erosion is the biggest unknown in the government’s calculations, one of the Justice Department’s experts, Ronald Dykhuizen, said in a video played during the hearing.

Brock said the government has never used the blowout preventer’s erosion in its analysis, and has stuck to estimates it published in August 2010.

However, the company’s expert on blowout preventers said in previous statements that erosion could have occurred in less than one second, O’Rourke said.

The company and U.S. officials also differ on the sandstone’s compressibility, a factor that affects how fast oil can flow out of the well. O’Rourke said BP changed its mind on the rocks’ level of porousness after the fact, while Brock of BP argued that more porous estimates the government points to were only used as a safety measure leading up to the days of capping the well.

Expert witnesses will continue to testify on behalf of the government Monday afternoon, and witnesses for BP are expected to take the stand later this week.

Follow the legal arguments as energy reporter Collin Eaton tweets from inside the courtroom: