NEW ORLEANS — Crews late today began setting fire to oil leaking from the site of an exploded drilling rig in the Gulf of Mexico, a last-ditch effort to get rid of it before it reaches environmentally sensitive marshlands on the coast.
A 500-foot boom will 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, the Coast Guard said. Such burns will continue throughout the day if they are working.
The slick was about 20 miles east of the mouth of the Mississippi River.
About 42,000 gallons of oil a day are leaking into the Gulf from the blown-out well where the Deepwater Horizon exploded and sank last week. 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. The last time crews with his agency used fire booms to burn oil was a 1995 spill on the San Jacinto River.
“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.”
He said the oil likely will be ignited using jelled gasoline and lit rags soaked in oil. What’s left afterward is something he described as a kind of hardened tar ball 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 no impact on sea turtles and marine mammals in the burn area.
A graphic posted by the Coast Guard and industry task force fighting the slick shows it covering an area about 100 miles long and 45 miles across at its widest point.
Louisiana State Wildlife and Fisheries Secretary Robert Barham told a legislative committee this morning that National Oceanographic and Atmospheric Administration projections show a “high probability” oil could reach the Pass a Loutre wildlife management area by Friday night, Breton Sound by Saturday and the Chandeleur Islands by Sunday.
As the task force worked far offshore, local officials were mobilizing in case the oil reaches land.
In Plaquemines Parish, a sliver of Louisiana that juts into the Gulf and is home to Pass a Loutre, officials hoped to deploy a fleet of volunteers in fishing boats to spread booms that could block oil from entering inlets.
“We’ve got oystermen and shrimpers who know this water better than anyone,” said Plaquemines Paris President Billy Nungesser. “Hopefully the Coast Guard will embrace the idea.”
The parish’s emergency manager planned to meet in Houma on Thursday with a Coast Guard official to discuss whether volunteers can help, Nungesser said.
“We don’t want to just sit by and hope this (oil) doesn’t come ashore,” Nungesser said.
The decision to burn some of the oil comes as the Coast Guard and industry cleanup crews run out of other options to get rid of it.
Crews operating submersible robots have been trying without success to activate a shut-off device that would halt the flow of oil on the sea bottom 5,000 feet below.
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 lessened. 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 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.