Congress questions BP's use of dispersants in Gulf

WASHINGTON (Reuters) - BP's use of dispersant chemicals on the Gulf of Mexico oil spill is sparking questions from a U.S. congressional panel, which says the company used more of these compounds than the U.S. Environmental Protection Agency had directed.

But the EPA indicated in a statement on Sunday that the difference between what the agency directed and what BP and the U.S. Coast Guard achieved is slight -- the difference between a 75 percent cut in dispersant use and a 72 percent cut.

The environmental agency acknowledged, however, that the use of dispersants is "always a difficult decision."

Environmental advocates have raised concerns about the use of dispersants to break up oil from the BP spill, on the grounds that the reddish bits of dispersant-treated oil may harm wildlife in the water column between the mile-deep well-head and the Gulf's surface.

Representative Ed Markey, who chairs the House of Representatives subcommittee on energy and environment, said in a letter to retired U.S. Coast Guard Admiral Thad Allen, the national incident commander overseeing the spill cleanup, that more information is needed on BP's dispersant use.

At the heart of the questions is a May 26 directive from EPA Administrator Lisa Jackson and then-on-scene coordinator Admiral Mary Landry, making the use of dispersants a last resort and ordering BP to cut the use of these chemicals by 75 percent from a peak of 70,000 gallons (260,000 liters) used on May 24.

EPA said on Sunday that from the time the directive was issued, dispersant use dropped 72 percent from its peak usage.

The directive allowed the Coast Guard to grant waivers for the use of more dispersant than the directive stipulated, but said these should be issued in "rare cases."

"TOXIC STEW"

Markey said in his Friday letter to Allen that "... these exemptions are in no way a 'rare' occurrence, and have allowed surface application of dispersant to occur virtually every day since the directive was issued."

Markey said dispersants "have been used both above and below the surface of the Gulf waters, contributing to a toxic stew of chemicals, oil and gas with impacts that are not well understood."

EPA said in its statement that "While EPA may not have concurred with every individual waiver ... the agency believes dispersant use has been an essential tool in mitigating this spill's impact, preventing millions of gallons of oil from doing even more damage to sensitive marshes, wetlands and beaches and the economy of the Gulf coast."

Asked about EPA's statement that it might not agree with all the waivers granted, an official at the Department of Homeland Security said EPA designated Allen, the federal on-scene coordinator, as the final authority on the spill.

In deciding whether or not to approve waivers, Allen considered a number of factors, including aerial photos of oil "that was going to reach the shore if it was not dispersed," the homeland security official said, speaking on condition of anonymity.

"This has been a coordinated federal response," the official stressed.

"Communications between the leaders of the various agencies have been thorough and robust. The tactics that were eventually deployed were the result of the collective will of the agencies involved in the response," he said.

(Editing by Eric Beech)