VENICE, La. — An oil spill that threatened to eclipse even the Exxon Valdez disaster spread out of control with a faint sheen washing ashore along the Gulf Coast on Thursday night as fishermen rushed to scoop up shrimp and crews spread floating barriers around marshes.
The spill was bigger than imagined — five times more than first estimated — and closer. Faint fingers of oily sheen were reaching the Mississippi River delta, lapping at the Louisiana shoreline in long, thin lines. "It is of grave concern," said David Kennedy of the National Oceanic and Atmospheric Administration. "I am frightened. This is a very, very big thing. And the efforts that are going to be required to do anything about it, especially if it continues on, are just mind-boggling."
The slick could become the nation's worst environmental disaster in decades, threatening hundreds of species of fish, birds and other wildlife.
The spill, caused by an explosion on April 20, is estimated to be leaking as many as 210,000 gallons of crude a day. It could continue for weeks.
President Barack Obama stepped up federal efforts to help clean up the spill in the Gulf of Mexico, putting the Department of Defense at the ready and dispatching three Cabinet officers to the scene.
Biologists from the state Fish and Wildlife Conservation Commission are scattered around Florida's coast, taking a "before" snapshot so they can better assess any damage should the spill reach here, according to David Palandro, the FWC's scientific support coordinator for oil spills.
They are taking water samples, checking the plankton population, testing the oysters in the Panhandle, Palandro said. "All this is to try to paint a picture of what's, quote unquote, 'normal,' " he explained.
Florida officials can deploy a system of booms to block oil from reaching the portion of the state's coastline that's most at risk, Palandro said, "but we're not sure where to put it yet." The spill is like a hurricane barreling through the gulf, he said: "We have a cone of uncertainty — and it's big."
Projections by NOAA suggest that the slick may reach Pensacola's sugar-white beaches by Sunday or Monday.
The oil that first hits the shore is likely to be "weathered," and thus less toxic, from having been in the gulf for several days, said Doug Helton, NOAA's chief oil spill response expert. But the oil that follows will likely be thicker, and as the spill continues it will be harder to protect the coast.
"We're going to do our best to minimize the damage," he said. "We're not going to prevent it from happening."
The Coast Guard worked with BP, which operated the oil rig, to set fires to burn the oil off the water's surface. The Coast Guard abandoned that plan after sea conditions deteriorated.
In the three months it could take to drill a relief well, the spill could easily eclipse the 11 million gallons that leaked from the Exxon Valdez in Alaska's Prince William Sound in 1989.
BP has already contacted Lee Fox, executive director of Save Our Seabirds of Sarasota, to be ready to roll when the slick shows up on a Florida coast. Fox, who oversaw the rescue of seabirds during the 1993 tanker spill in Tampa Bay, wrote a manual for how to handle oiled-up birds.
"They told us we'll probably be called up Sunday or Monday," said Fox, who lives in Wimauma. She has already packed a van full of medical equipment, towels and tubs, plus 75 cages and lots of Dawn dishwashing liquid.
"There is something in that Dawn detergent that cuts that oil right off of them," she said.
The spill has complicated Obama's plan to expand drilling. A spokesman said — at least for now — Obama remains committed to offshore drilling.
Sen. Bill Nelson, D-Fla., meanwhile, filed legislation blocking the Interior Department from conducting seismic tests in the Atlantic as part of its plan to expand offshore drilling.
Pundit Rush Limbaugh, who has a home on Florida's Palm Beach, suggested that the explosion could have resulted from Earth Day eco-sabotage by one of the rig workers. Limbaugh also said a cleanup was unnecessary.
"The ocean will take care of this on its own if it was left alone and left out there," Limbaugh said. "It's natural. It's as natural as the ocean water is."
Obama dispatched Homeland Security Secretary Janet Napolitano, Interior Secretary Ken Salazar and Environmental Protection Agency administrator Lisa Jackson to help with the spill.
Napolitano announced the creation of a second command post in Mobile, Ala., in addition to the one in Louisiana, to manage coastal impact in Alabama, Mississippi and Florida. Salazar ordered an immediate review of 30 offshore drilling rigs.
Times staff writer Craig Pittman contributed to this report, which contains information from Associated Press and McClatchy Newspapers.