The Demo Site

One nudge by a deep-sea robot, and BP had to back off its most effective method so far for containing the Gulf of Mexico oil leak.

After being removed for much of the day Wednesday, engineers using remote-controlled submarines repositioned a cap that had captured 700,000 gallons of oil in 24 hours before one of the robots bumped into it late in the morning.

Bob Dudley, BP's new point man for the oil response, said crews had done the right thing to remove the cap because fluid seemed to be leaking and could have been a safety hazard. The logistics coordinator onboard the ship that has been siphoning the oil told The Associated Press that the system was working again but it would take a little time before for the system to "get ramped back up." He asked not to be identified by name because he was not authorized to provide the information.

"It's a setback, and now we will go back into operation and show how this technology can work," Dudley said before the system was working again.

While the cap was off, clouds of black oil gushed unchecked again at up to 104,000 gallons per hour, though a specialized ship at the surface managed to suck up and incinerate 438,000 gallons.

The oil-burning ship is part of an armada floating at the site of the rogue well some 50 miles off the Louisiana coast, and the scene below the surface is no less crowded. At least a dozen robotic submarines dangle from ships at the surface on mile-long cables called "umbilicals," with most of the undersea work taking place within a few hundred yards of the busted well.

Crews of three operate each machine from control stations using joysticks and banks of video screens, inching them through the small portions of the pitch-black water that the submarines' headlamps can illuminate. Sometimes the water gets so murky that the controllers operate essentially by sound — the robots can map their surroundings using sonar.

Using the machines' mechanical arms, highly trained pilots routinely perform delicate jobs such as switching valves on, turning wrenches and grasping wires no thicker than a phone cord. Accomplishing even the smallest of tasks at such depths with robots the size of Humvees can be so tricky that experts compare it to remote-control surgery.

Only one other time during the attempts to contain the nine-week-old leak — when a submarine jarred loose a tube that been sucking oil from the broken riser — has one of the robot crews interrupted those efforts, said Coast Guard Adm. Thad Allen, the Obama administration's lead spill responder.

"I think the fact that we've had two bumps that have had some kind of a consequence associated with them in the 60-plus days response is a pretty good record," he said. "It's never going to be risk-free out there, and we need to watch it very closely."

The latest problem in the effort to stop the gusher came as thick pools of oil washed up on Pensacola Beach in Florida, and the Obama administration sought to resurrect a six-month moratorium on deepwater drilling.

Wednesday's disruption "is obviously a very disappointing development in a long line of setbacks, and Louisianians are frankly tired of excuses from the government and BP," said Republican Sen. David Vitter of Louisiana.

The current worst-case estimate of what's spewing into the Gulf is about 2.5 million gallons a day. Anywhere from 67 million to 127 million gallons have spilled since the April 20 explosion on the Deepwater Horizon rig that killed 11 workers and blew out the well 5,000 feet underwater. BP PLC was leasing the rig from owner Transocean Ltd.

When the robot bumped into the equipment just before 10 a.m., gas rose through a vent that carries warm water down to prevent ice-like crystals from forming in the machinery, Allen said. Crews were checking to see if the crystals called hydrates had formed before attempting to put the cap back on.

Last month, a similar problem with a cap doomed the effort to put a bigger containment device over the blown-out well. BP had to abandon the four-story box after the crystals clogged it, threatening to make it float away.

The smaller cap, which had worked fine until now, had been in place since June 4.

In Florida, thick pools of oil washed up along miles of national park and Pensacola Beach shoreline as health advisories against swimming and fishing in the once-pristine waters were extended for 33 miles east from the Alabama line.

"It's pretty ugly, there's no question about it," said Florida Gov. Charlie Crist.

The oil reeked as it baked in the afternoon heat on a beach that looked as if it had been paved with a 6-foot-wide ribbon of asphalt.

"This used to be a place where you could come and forget about all your cares in the world," said Nancy Berry, who fought back tears as she watched her two grandsons play in the sand far from the shore.

Park ranger Bobbie Visnovske said a family found an oily young dolphin beached in the sand in the Gulf Islands National Seashore Wednesday. Wildlife officers carried it into shallow water to revive it. They later transported it to a rehabilitation center in Panama City, about 100 miles to the east.

Meanwhile, the Obama administration was plotting its next steps after U.S. District Judge Martin Feldman in New Orleans overturned a moratorium on new drilling. In court papers, the Justice Department said it has asked a judge to delay the ruling. The Interior Department imposed the moratorium last month, halting approval of any new permits for deepwater projects and suspending drilling on 33 exploratory wells.

Feldman, appointed by President Ronald Reagan in 1983, has reported extensive investments in the oil and gas industry, including owning less than $15,000 of Transocean stock, according to financial disclosure reports for 2008, the most recent available. He did not return calls seeking more information about his investments.

Interior Secretary Ken Salazar said he would issue a new order within the next few days imposing a moratorium that eliminates any doubt it is needed and appropriate.

"It's important that we don't move forward with new drilling until we know it can be done in a safe way," he told a Senate subcommittee Wednesday.

Several companies, including Shell and Marathon Oil, said they would await the outcome of any appeals before they resume drilling.