Bobby Bolton, BP wellsite leader, talks to reporters on the Helix Q4000, which is performing the static kill procedure, at the site of the Deepwater Horizon Oil Spill in Gulf of Mexico, off the coast of Louisiana, Tuesday, Aug. 3, 2010.Gerald Herbert/AP
BP is turning the corner on its environmental catastrophe in the Gulf of Mexico, after the company managed to seal its rogue well and U.S. government officials said three-quarters of the spewed crude has been either captured or dispersed into small, fairly harmless droplets.
The company declared it had achieved a "static kill," eliminating the pressure on the temporary cap that had been in place for the past three weeks. BP expected to proceed with cementing-in the well for a permanent seal, an operation that the company hoped to commence Wednesday night after getting approval from government scientists.
Under siege for 3 1/2 months, BP is finally putting the most acute phase of the crisis behind it, allowing the company to focus on cleaning up the Gulf coast and dealing with the financial and operational challenges raised by the blowout. The spill has hammered BP, which estimates it faces $32-billion (U.S.) in cleanup costs, compensation and fines, while clobbering the company's stock and forcing asset sales and leadership changes.
Federal scientists reported on Wednesday that 76 per cent of the crude has either evaporated or been burned, skimmed or captured from the wellhead, or dispersed.
They estimated that 25 per cent of the total was captured or burned; 24 per cent was dispersed, either naturally or chemically, and is breaking down into harmless molecular components; 25 per cent evaporated or dissolved; and 26 per cent remains on or near the surface of the water or on the shore.
"There's absolutely no evidence that there's any significant concentration of oil that's out there that we haven't accounted for," said Jane Lubchenco, head of the National Oceanic and Atmospheric Administration, the lead agency in producing the new report.
She emphasized, however, that the government remained concerned about the ecological damage that has already occurred and the potential for more, and said it would continue monitoring the Gulf.
"I think we don't know yet the full impact of this spill on the ecosystem or the people of the Gulf," Dr. Lubchenco said.
Gulf Coast communities and the ocean ecosystem remain under threat from the remaining oil - a quantity larger than the spill from the Exxon Valdez - and from the subsurface brew of oil and chemical dispersants that were used to break down the crude before it hit the coast.
At a U.S. Senate committee hearing in Washington, several senators expressed concern about the unprecedented amount of toxic dispersants that had been used, and the long-term effect the chemicals may have on plankton - a critical part of the food chain - and on immature fish, oysters and shrimp.
At the site of the Macondo accident, BP managed to pump heavy drilling fluids into the well at 1,515 metres beneath the ocean surface, and offset the pressure from the reservoir below, effectively killing the blowout.
"I want to emphasize that BP remains committed to getting this well permanently abandoned, cleaning up any pollution and restoring the Gulf coast," Ken Wells, the company's senior vice-president, told a conference call. "That was our commitment from the beginning and we're just as committed today to those objectives."
As a result, the company will proceed with its relief wells, which would intersect the original bore 5,400 metres beneath the ocean surface, near the reservoir, and pump concrete into the base of the well to ensure there is no leakage.
The April 20 blowout gushed some 4.9 million barrels of crude into the Gulf of Mexico, resulting in untold damage to aquatic life, the closure of fisheries and a crippling of the region's lucrative summer tourist business.
Critics say the scientists are counting as "dispersed" the oily particles that are beneath the surface and may be doing serious damage to marine life.
"It's not surprising that the oil has dissipated and thus disappeared so quickly," said John Hofmeister, former president of Royal Dutch Shell PLC's U.S. operations.
"The government's approval of the vast amounts of dispersants is partly responsible, regardless of its otherwise deleterious impact on marine life. They'd rather see the oil disappear than protect nature that can't be seen."
The combination of dispersants, warm, rough water and natural microbes has broken much of the oil into microbial sizes. "Oil is simply old biomass and when it breaks down into its molecular sizes it is consumable by organisms in the sea," Mr. Hofmeister said. And the process can deplete the area of oxygen, posing further threats to sea life.
In Washington on Wednesday, Senator Barbara Boxer questioned the government's approval for BP to use some seven million litres of dispersant, including one brand, Corexit, that the Environmental Protection Agency eventually ordered the company to stop using.