The Coast Guard approved dozens of requests by BP to spread hundreds of thousands of gallons of surface oil dispersants in the Gulf of Mexico despite the Environmental Protection Agency’s directive on May 26 that they should be used only rarely, according to documents and correspondence analyzed by a Congressional subcommittee.
In some cases, the Coast Guard approved BP’s requests even though the company did not set an upper limit on the amount of dispersant it planned to use.
The dispersants contributed to “a toxic stew of chemicals, oil and gas, with impacts that are not well understood,” Representative Edward J. Markey of Massachusetts, the Democratic chairman of the House Subcommittee on Energy and Environment, wrote in a letter sent late Friday to Thad W. Allen, the retired Coast Guard admiral who is leading the federal response to the oil spill.
In a conference call on Saturday morning, Admiral Allen and Lisa P. Jackson, the E.P.A. administrator, said they had worked together closely and had come very near to achieving the agency’s goal of reducing dispersant amounts by 75 percent.
On May 26, the E.P.A. directed BP to stop using dispersants on the ocean surface, except in “rare cases when there may have to be an exemption,” and to limit use of the chemicals underwater.
But Mr. Markey’s letter pointed to more than 74 exemption requests in 48 days, of which all but 10 were fully approved by the Coast Guard. In some cases, BP asked for permission after it had already applied the chemicals, the letter said. And in one case, the Coast Guard approved the use of a larger volume of dispersants than the company had applied for.
As an example of the conflicting numbers, Mr. Markey said that in a request filed on June 16, BP told the Coast Guard that in the previous several days it had used a maximum of 3,365 gallons of dispersant in a single day. But in e-mails to members of Congress giving updates on the spill response, the company said it had used 14,305 gallons of dispersant on June 12 and 36,000 gallons on June 13.
Admiral Allen and Ms. Jackson said they had reduced dispersant use by 72 percent. “In any government program I’ve worked in, that’s pretty significant progress,” Admiral Allen said.
Admiral Allen said his agency would try to reconcile the conflicting numbers that were issued during what he called “the equivalent of an environmental war.”
The two officials said the government would conduct a postmortem evaluation of the effectiveness of skimming, burning and spreading dispersants to determine what had worked best.
But Ms. Jackson said, “There’s absolutely no doubt that use of dispersants was one of several essential tools to mitigate this spill’s impact.”
A spokesman for BP, Scott Dean, also said he could not respond in detail because the company had not seen Mr. Markey’s letter. But he said, “From the outset we’ve operated in a unified command that has included E.P.A. and the Coast Guard.”
Mr. Dean said BP had worked “hand in glove” with the two agencies on dispersant decisions. Under the “joint command” structure set up in the Oil Pollution Act of 1990, the federal government and the oil company mount a response to a spill.
While it was known that BP continued the use of surface dispersant after the May 26 directive, it was not clear how much was being used. According to the documents analyzed by the committee, the company did cut back substantially on the use of underwater dispersants after the directive was issued.
The E.P.A. and the Coast Guard have both described the use of the dispersants as a trade-off. The chemicals break down blobs of oil into smaller droplets that are easier for naturally occurring bacteria to digest. But they can also have harmful effects on marine animals. And if the dispersants are too successful and allow a proliferation of bacteria, the bacteria can use up all the oxygen in the water and kill the fish and other organisms.
In testimony before Congress on July 15, Ms. Jackson said her agency had been looking for signs of unusually low oxygen levels and had not found them.
In his letter, Mr. Markey said the May 26 directive had “become more of a meaningless paperwork exercise than an attempt to abide by the directive and eliminate surface applications of chemical dispersants.”
In fact, other government correspondence disclosed by Mr. Markey indicates a dispute within the E.P.A. about the proper use of dispersants. At one point, the Dallas regional office of the agency agreed that the incident command center, run by the Coast Guard and BP, should get blanket approval to use 5,000 gallons of dispersant a day, to “improve operational efficiency.”
But the next day, the Dallas office rescinded that policy, saying that the center should make a request each evening about the amount it wanted to use the next day and that the agency would make a decision overnight.
Mr. Markey said that while the agency said on May 26 that applications for surface dispersant use should be rare, the Coast Guard, in approving the applications, cited routine factors like there being too much oil to skim.