With fears growing that the gushing well could spread damage from Louisiana to Florida, Interior Secretary Ken Salazar told a Senate panel Tuesday that his agency had been lax in overseeing offshore activities and that may have contributed to the disastrous spill.
"There will be tremendous lessons to be learned here," Salazar said in his first appearance before Congress since the April 20 blowout and explosion on the Deepwater Horizon rig that killed 11 people.
Coast Guard Adm. Thad Allen told another committee that the growing size and scattershot nature of the spill were creating "severe challenges" in containing it and cleaning it up. He called it more complicated than any spill he's ever seen.
"What we're basically trying to do is protect the whole coast at one time," Allen said.
Special Section: Disaster in the Gulf
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The House Transportation and Infrastructure Committee was set to address the spill at a hearing Wednesday.
Government scientists, meanwhile, were surveying the Gulf to determine if the oil had entered a powerful current that could take it to Florida and eventually up the East Coast. Tar balls that washed up on Florida's Key West were shipped to a Coast Guard laboratory in Connecticut to determine if they came from the spill.
Questions remained about just how much oil is spilling from the well, and senators expressed frustration about a lack of answers during a full day of hearings that included top executives from BP PLC, the oil giant that leased the blown well, and Transocean Ltd., the rig owner.
New underwater video released by BP showed oil and gas erupting under pressure in large, dark clouds from its crippled blowout preventer on the ocean floor. The leaks resembled a geyser on land.
Under Pressure from Congress, BP Releases Video
When CBS News tried to reach the beach, covered in oil, a boat of BP contractors with two Coast Guard officers on board told the crew to turn around under threat of arrest. Coast Guard officials said they are looking into the incident.
Salazar promised an overhaul of federal regulations and said blame rests with both industry and the government, particularly his agency's Minerals Management Service.
"We need to clean up that house," Salazar said of the service.
Some 5 million gallons of crude has spewed into the Gulf.
National Oceanic and Atmospheric Administration Administrator Jane Lubchenco says aerial surveys show some tendrils of light oil close to or already in the loop current, which circulates in the Gulf and takes water south to the Florida Keys and the Gulf Stream. But most oil is dozens of miles away from the current.
Lubchenco says it will take about eight to 10 days after oil enters the current before it begins to reach Florida. But scientists from the University of South Florida are forecasting it could reach Key West by Sunday.
The Coast Guard said the Florida Park Service found the tar balls on Monday during a shoreline survey. The balls were 3-to-8 inches in diameter.
Coast Guard Lt. Anna K. Dixon said no one at the station in Key West was qualified to determine where the tar balls originated. They have been sent to a lab for analysis.
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