Government, BP to Revise Estimated Rate of Oil Leak

BY Lea Winerman  May 21, 2010 at 4:56 PM EST

Phil Radford, executive director of Greenpeace USA, inspects oil-covered reeds along the Gulf of Mexico; John Moore/Getty Images Phil Radford, executive director of Greenpeace USA, inspects oil-covered reeds along the Gulf of Mexico; John Moore/Getty Images

Questions continued to swirl over the size of the Deepwater Horizon oil leak, as BP and the Coast Guard announced Friday that a new “flow rate technical team” comprised of outside experts and multiple government agencies would begin work on a new estimate of the leak’s magnitude.

Coast Guard Rear Adm. Mary Landry said in a press briefing that the panel would include a scientist who has been a leading critic of the original estimate.

Until Thursday, BP and NOAA had stood by their early estimate — produced April 29 — that about 5,000 barrels (210,000 gallons) were leaking per day from the damaged well, although they had acknowledged that the estimate was not precise.

But on Thursday, BP said that a pipe it had inserted to divert oil to the surface was bringing up 5,000 barrels per day — while a live undersea video camera viewable online showed still more oil gushing from the well. However, according to Reuters:

BP revised downward on Friday an estimate from Thursday that one of its containment solutions — a 1 mile (1.6 km)-long siphon tube inserted into the larger of two seabed leaks — was capturing 5,000 barrels (210,000 gallons/795,000 litres) of oil per day.

“The flow changes, it’s not constant,” BP spokesman John Curry said.

Still, Thursday’s news only added to the increasing pressure on BP from outside scientists, the federal government and the public to come up with a better estimate of the amount of oil spilled and to make more data on the leak publicly available. Critics have charged that BP stands to gain by keeping the flow rate unclear, because the size of the spill could affect damage claims in the lawsuits that are sure to come.

“If they put off measuring, then it’s going to be a battle of dueling experts after the fact trying to extrapolate how much spilled after it has all sunk or has been carried away,” Lloyd Benton Miller, one of the lead plaintiffs’ lawyers in the Exxon Valdez litigation, told McClatchy News Service.

In a letter to BP CEO Tony Hayward, EPA administrator Lisa Jackson and Homeland Security head Janet Napolitano asked BP to release all data related to measurements of the leak, as well as air and water quality and dispersant use.

And Thursday, BP agreed to a request by Rep. Edward J. Markey, D-Mass., chair of the House Select Committee on Energy Independence and Global Warming, to post a live streaming video of the well online. Before, the company had made only short snippets of video available.

Outside scientists analyzing those videos have estimated that the well could be leaking 10 to 20 times NOAA’s 5,000 barrel-per-day estimate, while acknowledging that without more information a precise estimate is impossible to come by.

Steve Wereley, an expert on fluid dynamics from Purdue University, has been one of the most quoted on the topic. He testified before Congress Wednesday that according to his analysis, the well could be gushing up to 95,000 barrels per day from multiple holes.

BP disputed that estimate. In a news release Friday, the company said that it was based on a faulty assumption that the entire pipe is open, whereas in reality the opening is about 30 percent smaller because it was distorted in the explosion. Also, the company said, the pipe is releasing both oil and natural gas, something Wereley’s analysis does not take into account.

On Friday, Wereley told the Houston Chronicle that after watching the live feed of the leak, he might revise his estimate in half.

“When I did my calculation, BP had given me and the general public almost no explanation, so I had to make a number of assumptions in my analysis,” he said.

Wereley will be contributing to the new Flow Rate Technical Team’s analysis, the Coast Guard’s Landry said Friday. BP had originally said that the team’s new estimate would be available by Saturday night, but Landry said in a news conference that the team might need more time to produce an accurate estimate and that their results would be available sometime next week.

BP is still trying to plug the oil leaks, hopefully within the next few days, Managing Director Robert Dudley told The NewsHour on Wednesday.