By daybreak, all but a handful of the ships working at the well site were expected to remain at sea. The vessels relaying video images and seismic readings from undersea robots monitoring BP's broken oil well will be among the last to leave, and may stay and ride out the rough weather, retired Coast Guard Adm. Thad Allen said.
Bonnie made landfall south of Miami early Friday as a feeble tropical storm with top sustained winds of 40 mph (65 kph). It broke apart as it crossed Florida and was a tropical depression as it moved into the Gulf, but forecasters expected it to strengthen slightly and roll over the spill site around midday Saturday.
The mechanical cap that has mostly contained the oil for eight days will be left closed, Allen said. But if the robots are reeled in, the only way officials will know whether the cap has failed will be if oil pooling on the surface appears in satellite and aerial views — if the clouds aren't too thick.
"Preservation of life and preservation of equipment are our highest priorities," said Allen, the federal government's spill chief who ordered the evacuation of most ships 40 miles (65 kilometers) from the Louisiana coast Workers on land readied for a possible storm surge that could push oil into the sensitive marsh areas along the coast.
On the tiny resort island of Grand Isle off the southeast Louisiana coast, workers packed up the oil removal operation, tearing down tents, tying down clean boom and loading oil-soaked boom into large containers so it won't pollute the area if the storm causes flooding.
"We're planning for a 2-to-3 foot storm surge so anything that would be affected by that is being moved or stored," said Big Joe Kramer, 55, who is working on his fourth large spill for Miller Environmental Services, Inc.
At the spill site, the water no longer looks thick with gooey tar. But the oil is still there beneath the surface, staining the hulls of boats motoring around in it.
Before the cap was attached and closed a week ago, the broken well spewed 94 million gallons (355 million liters) to 184 million gallons (696 million liters) into the Gulf after the BP-leased Deepwater Horizon rig exploded April 20, killing 11 workers.
The plug is so far beneath the ocean surface, scientists say even a severe storm shouldn't damage it.
"There's almost no chance it'll have any impact on the well head or the cap because it's right around 5,000 feet deep and even the largest waves won't get down that far," said Don Van Nieuwenhuise, director of professional geoscience programs at the University of Houston.
Crews of other vessels, including one boring the tunnel meant to kill the flow of crude for good, spent Friday hauling in their gear and getting out of the storm's way.
Workers were pulling up a mile of pipe in 40-to-60-foot (12-to-18 meter) sections and laying it on deck of the drilling rig so they could move to safer water, probably to the southwest flank of the storm.
Shell Oil also was evacuating its operations in the Gulf, moving out more than 600 workers and shutting down production at all but one well sheltered safely in Mobile Bay.
