Emergency officials along the Gulf Coast are preparing for an environmental disaster should a massive oil spill in the Gulf of Mexico reach the shore.
Workers are trying to contain a 42,000-gallon-a-day leak from the site of a deepwater oil rig explosion last week.
Crews will begin drilling by Thursday as part of a $100 million effort to take the pressure off the well, said BP, which operates the rig that exploded last week.
Company spokesman Robert Wine said it will take up to three months to drill a relief well from another rig recently brought to the site where the Deepwater Horizon sank after the blast. Most of the 126 workers onboard escaped; 11 are missing and presumed dead. No cause has been determined.
Meanwhile, congressional lawmakers have asked Transocean Ltd., the rig's owner, and BP for documents as part of an investigation into the accident.
The oil slick caused by the explosion is growing despite ongoing cleanup efforts. Underwater, robotic submarines are trying to shut off the oil at its source, but they have been unable to activate a shutoff device at the head of the well. A kink in the pipe is keeping oil from flowing even more heavily.
Northwest winds have helped keep the oil offshore, but forecasters say the wind will shift out of the south later this week, which could push the slick closer to the northern Gulf Coast. Emergency officials from Venice, La., to Pensacola, Fla., are preparing for shoreline impacts, which threaten wildlife, tourism and fisheries.
Florida's Republican Gov. Charlie Crist says the offshore accident has him rethinking his position on oil and gas development off the Florida coast.
"If this doesn't give somebody pause, there's something wrong," Crist said.
If the well cannot be closed, almost 100,000 barrels -- 4.2 million gallons -- of oil could spill into the Gulf before the relief well is operating.
Material from The Associated Press was used in this report