NEW ORLEANS (AP) -- A cap was back in place on BP's broken oil well after a deep-sea blunder forced crews to temporarily remove what has been the most effective method so far for containing some of the massive Gulf of Mexico spill.
Engineers using remote-controlled submarines repositioned the cap late Wednesday after it had been off for much of the day. It 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.