Updated

MOBILE, Alabama -- The winds and waves eased in the Gulf of Mexico on Tuesday, an encouraging development for crews trying clean up a massive oil spill, yet an official with BP PLC said more than 20 boats were looking into an unconfirmed report of oil coming ashore in Louisiana.

People along the beaches and bayous waited anxiously to find out just how badly it might damage the delicate coast.

The calm weather was allowing cleanup crews to put out more containment equipment and repair some of the protective booms that were damaged in the rough weather. They also hoped to again try to burn some of the oil on the water's surface, possibly Wednesday.

The Marine Spill Response Corp. had five, 210-foot vessels designed for oil skimming operating offshore Tuesday. Three more were at sea preparing to lower their equipment so they could suck up oil as well.

A Coast Guard official said forecasts showed the oil wasn't expected to come ashore until at least Thursday.

"It's a gift of a little bit of time. I'm not resting," U.S. Coast Guard Rear Adm. Mary Landry said.

Near Port Fourchon, southwest of New Orleans, workers for contractor Wild Well Control were busy welding and painting a massive containment device. BP spokesman John Curry said it would be deployed on the seabed by Thursday.

That wasn't much comfort to the hotel owners, fishing boat captains and others who rely on the ocean to make a living.

"The waiting is the hardest part. The not knowing," said Dodie Vegas, 44, who runs the Bridge Side Cabins complex in Grand Isle, a resort and recreational fishing community that's just about as far south in Louisiana as you can go. So far, two fishing rodeos have been canceled, and 10 guests have canceled their rooms.

The drilling rig Deepwater Horizon exploded April 20, killing 11 workers and sending hundreds of thousands of gallons of oil a day gushing into the Gulf. The rig was owned by Transocean Ltd.

BP executives told members of a congressional committee that in a worst-case scenario, up to 2.5 million gallons a day could spill, though it would be more like 1.7 million gallons.

While a rainbow sheen of oil has reached land in parts of Louisiana, the gooey rafts of coagulated crude have yet to come ashore in most places.

Officials couldn't confirm reports that some of it reached the delicate Chandeleur Islands off the coast of Louisiana on Tuesday. The Associated Press reported oil had come ashore at the mouth of the Mississippi last week.

The slow movement has given crews and volunteers time to lay boom in front of shorelines, an effort stymied by choppy seas over the weekend.

BP PLC continued to try to cap one of the smaller of three leaks, which if successful, could make it easier to install a containment system over the well.

BP's chief executive said a containment dome designed to cover the principal leak will be on the seabed Thursday, and will be hooked up to a drill ship over the weekend.

CEO Tony Hayward stressed to reporters in Washington that the procedure had never been done before at a depth of nearly a mile below the water's surface.

"So we'll undoubtedly encounter some issues as we go through that process," he said. "But if that was a good outcome, then you would have the principal leak contained by the early part of next week. But there's no guarantees."

The plan is to cover the leak with a 98-ton concrete-and-metal box structure known as a cofferdam, and funnel the oil to the surface. Hayward also said that chemical dispersants being used on the oil have significantly reduced the amount of oil coming to the surface.

The uncertainty has been trying for people who live along a swath of the Gulf from Louisiana to Florida.

BP has been unable to shut off the well, but crews have reported progress with a new method for cutting the amount of oil that reaches the surface. They're using a remotely operated underwater vehicle to pump chemicals called dispersants into the oil as it pours from the well, to break it up before it rises. Results were encouraging but the approach is still being evaluated, BP and Coast Guard officials said.

The latest satellite image of the slick, taken Sunday night, indicates that it has shrunk since last week, but that only means some of the oil has gone underwater.

The new image found oil covering about 2,000 square miles, rather than the roughly 3,400 square miles observed last Thursday, said Hans Graber of the University of Miami.

Fishing has been shut down in federal waters from the Mississippi River to the Florida Panhandle, leaving boats idle Monday in the middle of the prime spring season. A special season to allow boats to gather shrimp before it gets coated in oil will close Tuesday evening.

The effect on wildlife is still unclear. No oil was found on 29 dead endangered Kemp's ridley turtles that were examined by experts after washing up on the beaches along the Mississippi coast over the past few days.

But Moby Solangi, director of the Institute for Marine Mammal Studies in Gulfport, said tissue samples would be sent off to labs for further review. Experts have warned that just because no oil is found on the turtles that doesn't mean they didn't consume contaminated fish or come into contact with toxins.

Meanwhile, crews haven't been able to activate a shutout valve underwater. Worse, it could take three months to drill sideways into the well and plug it with mud and concrete to stop the worst U.S. oil spill since the tanker Exxon Valdez ran aground in Alaska, leaking nearly 11 million gallons of crude.

BP said Monday it would compensate people for "legitimate and objectively verifiable" claims from the explosion and spill, but President Barack Obama and others pressed the company to explain exactly what that means.

Louisiana Gov. Bobby Jindal and other officials kept up their criticism of BP and the Coast Guard, saying they never provided plans to protect the Louisiana coast from an oil spill.

Jindal and Sen. David Vitter said local leaders have stepped in to come up with their own solutions and officials are waiting for the Coast Guard to approve the plans and BP to fund them.

"If it were up to the BP and the feds, we would not yet have plans," Vitter said.

By all accounts, the disaster is certain to cost BP billions. But analysts said the company could handle it; BP is the world's third-largest oil company and made more than $6 billion in the first three months of this year. The oil spill has drained $32 billion from BP's stock market value.