Stormy weather delayed weekend efforts to mop up leaking oil from a damaged well after the explosion and sinking of a massive rig off Louisiana's Gulf Coast that left 11 workers missing and presumed dead.
The leak was a new discovery Saturday and could have begun when the Deepwater Horizon drilling rig sank Thursday, two days after the initial explosion that sent smoke soaring high over the northern Gulf, Coast Guard Rear Adm. Mary Landry said.
Experts studying the size of the slick and data obtained from remotely operated vehicles estimate as much as 1,000 barrels — or 42,000 gallons — of oil is leaking each day. The sheen extended 20 miles by 20 miles Saturday — about 25 times larger than it appeared to be a day earlier, Landry said.
By comparison, Exxon Valdez spilled 11 million gallons in Alaska's Prince William Sound in 1989 — the worst oil spill in U.S. history.
For days, the Coast Guard had said no oil had appeared to be escaping from the well head on the Gulf floor. But the leak reported Saturday raised concerns about a possible environmental threat to the fragile marine ecosystem.
"This is a very serious spill, absolutely," Landry said.
BP PLC, which leased the rig and is taking the lead in the cleanup, and the federal government have been using the remotely operated vehicles to try to stop the leak by closing valves on the well deep underwater. If that doesn't work, the company could drill what's called an intervention well to control the oil flow. But intervention drilling could take months.
"Over the next several days, we should determine which method is the best one to follow," said Doug Suttles, chief operating officer for BP Exploration and Production.
BP said it has activated an extensive oil spill response, including the remotely operated vehicles, 700 workers, four planes and 32 vessels to mop up the spill.
The Marine Spill Response Corp., an energy industry cleanup consortium, also brought in equipment.
Complicating efforts to stop the leak is the well head's depth at 5,000 feet underwater, said Lars Herbst, the regional director for the Minerals Management Service. Leaks have been fixed at similar depths before, but the process is difficult, he said.
The bad weather began rolling in Friday as strong winds, clouds and rain interrupted efforts to contain the spill. Coast Guard Petty Officer John Edwards said he was uncertain when weather conditions would improve enough for cleanup to resume. So far, he said, crews have retrieved about 1,052 barrels of oily water.
The sunken rig may have as much as 700,000 gallons of diesel on board, and an undetermined amount of oil has spilled from the rig itself. Suttles said the rig was "intact and secure" on the seabed about 1,300 feet from the well site.
After days of efforts, the Coast Guard recently called off the search for the 11 workers missing after the blast and presumed dead.
The missing workers came from Texas, Louisiana and Mississippi. Neither the Coast Guard nor their employers have released their names, though several of their families have come forward.
Karl Kleppinger Sr., whose 38-year-old son, Karl, was one of the missing workers, said he doesn't blame the Coast Guard for recently calling off the search.
"Given the magnitude of the explosion and the fire, I don't see where you would be able to find anything," said Kleppinger, of Zachary, La.
The other 115 crew members made it off the platform; several were hurt but only one remained hospitalized.
The cause of Tuesday's blast hasn't been determined.
Associated Press Writer Noaki Schwartz reported from Los Angeles. Associated Press Writers Jason Dearen in San Francisco, Mike Kunzelman and Kevin McGill in Louisiana contributed to this report.
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