By Matthew Bigg
VENICE, Louisiana (Reuters) - The U.S. government scrambled on Friday to ward off an environmental disaster that could cost billions of dollars as a huge oil spill reached coastal Louisiana, imperiling shrimp fishing grounds, oyster beds and fragile wetlands with a rich variety of wildlife.
With oil gushing unchecked from a ruptured deepwater well in the Gulf of Mexico off Louisiana, President Barack Obama's administration heaped pressure on London-based energy giant BP, the majority owner of the blown-out well, to do more to shut off the flow and contain the spreading slick.
Obama, mindful of public criticism of President George W. Bush's handling of the 2005 Hurricane Katrina disaster, sent several top officials to Louisiana to assess preparations for the cleanup effort.
Interior Secretary Ken Salazar said he had told BP to "work harder and faster and smarter to get the job done."
"We cannot rest and we will not rest until BP permanently seals the wellhead and cleans up every drop of oil," Salazar said in Louisiana.
Crude oil is pouring out at a rate of up to 5,000 barrels a day,liters according to government estimates, but experts said the quantity of crude escaping was difficult to measure. Forecasters predict the spill will soon invade the coastlines of Mississippi as well as Alabama and Florida, which both declared states of emergency.
So far, efforts to plug the oil leak have failed. If unchecked, it will take about 50 days to eclipse the 1989 Exxon Valdez spill in Alaska, the worst U.S. oil spill, which sent 10.8 million gallons (49 million liters) of crude oil into Alaska's pristine Prince William Sound.
"The problem here is we have a leak that's uncontrolled right now, leading to a source of oil that's not infinite, but it's very very large, and we're not going to know the total impact and the oil release until we actually shut it down," Coast Guard Admiral Thad Allen said on CNN.
"I think 5,000 barrels per day is a good estimate for now, but I think we need to understand, we can have something catastrophic happen down there, we need to be prepared for the worst-case scenario, and that's where we're headed."
PRESSURE ON BP
Louisiana Governor Bobby Jindal, who is seeking to mobilize 6,000 National Guard troops, was worried about BP's ability to cope with the enormous challenges posed by the oil leak.
"I do have concerns that BP's current resources are not adequate" to meet three main challenges from the disaster: stopping the leak of oil from a damaged undersea well, protecting the coast and carrying out a swift cleanup," Jindal, told a news conference in Louisiana, where he was flanked by high-level federal officials.
The accident forced Obama to suspend politically sensitive plans to expand offshore U.S. oil drilling, which he unveiled last month, partly to woo Republican support for climate change legislation.
Obama said domestic oil drilling remained an important part of the U.S. energy policy, but insisted it must be done responsibly. The White House said no new areas of offshore oil drilling would be allowed until a review was conducted of the spill.
Homeland Security Secretary Janet Napolitano urged BP, whose CEO Tony Hayward promised an "aggressive" cleanup campaign, to commit more resources to the operation.
She said two Air Force C-130 aircraft equipped to spray dispersant chemicals were on their way to join the containment effort, which involves hundreds of boats and planes.
Hayward said BP would clean up the oil spill and compensate those affected. "We are taking full responsibility for the spill. ... We are going to be very, very aggressive in all of that," he told Reuters in London.
BP admitted it was struggling to control the leak, which is 5,000 feet down on the sea bed, and asked the Pentagon to supply underwater imaging technology and robots.
BOOMS 'NOT EFFECTIVE'
It could take weeks to stop the flow of oil and would require either trapping it and channeling it to a tanker, or drilling a relief well. Meanwhile, the Coast Guard deployed floating booms to try to protect the coastline.
Jindal said the booms were "not effective," although other officials said that was due partly to shifts in the weather.
"Weather is one of our biggest challenges. Wind and waves are up. Seas are at 6 to 8 feet, which can make it difficult to deploy boom," said Ayana Mcintosh-Lee, a BP spokeswoman.
Experts said there was little hope that BP would succeed with a relatively quick fix to cap the well.
"At 5,000 barrels a day, in two months' time it's going to be a bigger spill than the Exxon Valdez, said Tyler Priest, director of global studies at the University of Houston's Bauer College of Business. "You're looking at a huge disaster."
BP now hopes to cover the well with a giant inverted funnel that would capture the oil and channel it to a tanker ship.
But that would take four weeks, by which time over 150,000 barrels could have been spilled. If the funnel does not work, BP will have to try stemming the flow by drilling a relief well, which would take two to three months.
There are already signs the spill may be worse than one in 1969 off Santa Barbara, California, which prompted a moratorium on oil and gas drilling off the Pacific and Atlantic coasts -- a ban Obama had said he wanted to modify.
Officials said a "sheen of oil" from the 120-mile (193-km) oil slick had reached barrier islands in a Louisiana wildlife reserve on the fringes of the vast Mississippi Delta.
"So far, it's minimal oil that has come ashore, but when you look at the wind we have to prepare for the worst. ... If it goes inland, it will be massive and out of control," Plaquemines Parish President Bill Nungesser told Reuters.
"There are a lot of angry people right now," said Christopher Creppel, 25, a fisherman in Venice, Louisiana. "This will not just put us out of business this year. It will put us out of business for years to come."
The cost to Louisiana's fishing industry could be $2.5 billion and the impact on tourism along Florida's Gulf coast could be $3 billion, estimated Neil McMahon, analyst at investment firm Bernstein.
Shares of companies that provided services or operated the sunken Deepwater Horizon drilling rig, including Halliburton Co and Transocean Ltd, fell sharply as worry mounted about liability from the spill.
(Additional reporting by Chris Baltimore and Kristen Hays in Houston, Tom Bergin in London, Phil Stewart in Washington, Joshua Schnyer and Rebekah Kebede in New York; Writing by Christopher Wilson; Editing by Peter Cooney)