The test burn of an area about 30 miles east of the Mississippi River Delta will gauge the effectiveness of a plan to burn up an oil spill before it can wash ashore. About 42,000 gallons of oil a day are leaking into the Gulf of Mexico from the blown-out well.
The Coast Guard started a test burn of an area about 30 miles east of the Mississippi River Delta on Wednesday to see how a plan to burn up an oil spill before it could wash ashore and wreak environmental havoc was working.
Crews turned to the plan after failing to stop a 1,000-barrel-a-day leak at the spot where a deepwater oil platform exploded and sank. A 500-foot boom was to be used to corral several thousand gallons of the thickest oil on the surface, which will then be towed to a more remote area, set on fire and allowed to burn for about an hour.
NPR's Wade Goodwyn, who is at the Unified Command Center in Robert, La., said this isn't tried-and-true territory.
"Nobody is sure how well this is going to work in the open Gulf," Goodwyn told NPR's Melissa Block. "It's not going to be a large percentage of the spill because burning only works where the spill is thick, emulsified, and that's only about 3 percent of the entire oil sick."
He cautioned that even if the experiment works, it's not going to be a big fix. Goodwyn said the burning does not compare with planes dropping dispersants, which are having the most impact in controlling the spill.
About 42,000 gallons of oil a day are leaking into the Gulf of Mexico from the blown-out well drilled by the Deepwater Horizon oil rig. Eleven workers are missing and presumed dead. The cause of the explosion has not been determined.
Greg Pollock, head of the oil spill division of the Texas General Land Office, which is providing equipment for crews in the Gulf, said he is not aware of a similar burn ever being done off the U.S. coast.
"When you can get oil ignited, it is an absolutely effective way of getting rid of a huge percentage of the oil," he said. "I can't overstate how important it is to get the oil off the surface of the water."
The oil has the consistency of thick roofing tar.
When the flames go out, Pollock said, the material that is left resembles a hardened ball of tar that can be removed from the water with nets or skimmers.
"I would say there is little threat to the environment because it won't coat an animal; and because all the volatiles have been consumed if it gets on a shore, it can be simply picked up," he said.
Authorities also said they expect minimal impact on sea turtles and marine mammals in the burn area.
A graphic posted by the Coast Guard and the industry task force fighting the slick showed it covering an area about 100 miles long and 45 miles across at its widest point.
"It's premature to say this is catastrophic. I will say this is very serious," said Coast Guard Rear Adm. Mary Landry.
More than two dozen vessels moved about in the heart of the slick-pulling, oil-sopping booms.
As the task force worked far offshore, local officials prepared for the worst in case the oil reaches land.
Goodwyn said the oil is likely to come ashore around the Mississippi River Delta. He said the government and rig operator BP PLC both have about 100,000 feet of surface booms to put there; another 500,000 feet of booms are available. The slick is expected to hit Friday.
"There's no stopping this from coming ashore everywhere, and if it's going to be weeks of oil spilling out of this well before they can get it stopped, this could turn into quite an impressive mess," Goodwyn said.
The decision to burn some of the oil came after crews operating submersible robots failed to activate a shut-off device that would halt the flow of oil on the sea bottom 5,000 feet below.
BP says work will begin as early as Thursday to drill a relief well to relieve pressure at the blowout site, but that could take months.
Another option is a dome-like device to cover oil rising to the surface and pump it to container vessels, but that will take two weeks to put in place, BP said.
Winds and currents in the Gulf have helped crews in recent days as they try to contain the leak. The immediate threat to sandy beaches in coastal Alabama and Mississippi has eased. But the spill has moved steadily toward the mouth of the Mississippi River, home to hundreds of species of wildlife and near some rich oyster grounds.
The cost of the disaster continues to rise and could easily top $1 billion.
Industry officials say replacing the Deepwater Horizon, owned by Transocean Ltd. and operated by BP, would cost up to $700 million. BP has said its costs for containing the spill are running at $6 million a day. The company said it will spend $100 million to drill the relief well. The Coast Guard has not yet reported its expenses.
Material from NPR's Wade Goodwyn and the Associated Press was used in this report.
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