BP said Thursday the amount of crude oil captured by an underwater siphon had increased to about 5,000 barrels per day. The siphon is diverting the crude to a tanker on the surface of the gulf at the spot where the offshore drilling rig Deepwater Horizon exploded and sank April 20.
In addition, around 15 million cubic feet per day of natural gas is being captured and flared off on the surface.
Outside analysts have said in media reports the oil flow is much higher than BP estimated. BP America Chairman Lamar McKay said Wednesday the company's figure had a degree of uncertainty built into it, CNN reported.
Steve Wereley, a professor of mechanical engineering at Purdue University, said on CNN as much as 20,000 to 100,000 barrels of oil might be flowing into the gulf each day.
U.S. lawmakers Thursday released video from BP showing the damaged well was discharging much more oil than the siphon was capturing, CNN said.
"Most of the oil is gushing like mad out there, with just a little bit being siphoned off, which tells you there is a much greater volume than BP said," Sen. Barbara Boxer, D-Calif., who heads the Senate Environment and Public Works Committee, said.
"I think now we are beginning to understand that we cannot trust BP," Rep. Ed Markey, D-Mass., chairman of a House subcommittee looking into the Deepwater Horizon disaster, said.
"BP has lost all credibility," Markey said. "Now the decisions will have to be made by others, because it is clear that they have been hiding the actual consequences of this spill."
Homeland Security Secretary Janet Napolitano and Environmental Protection Agency head Lisa Jackson Thursday directed BP Chief Executive Officer Tony Hayward "to conduct all actions in a transparent manner, with all data and information related to the spill readily available to the U.S. government and the American people."
The EPA directed BP to "use a less toxic and more effective dispersant" than the one the company had been using for weeks on the spill.
"Plans continue to develop a so-called 'top kill' operation where heavy drilling fluids are injected into the well to stem the flow of oil and gas, followed by cement to seal the well," BP said in a written statement. "Most of the equipment is on site and preparations continue for this operation, with a view to deployment in the next few days."