ROBERT, Louisiana (Reuters) - BP Plc said on Monday it will again attempt to contain oil gushing deep in the Gulf of Mexico, this time with a far smaller funnel than it tried before, as a massive slick threatened Louisiana shores.
With cleanup efforts in high gear, a blame game will unfold in Washington on Tuesday as executives from BP and two other companies involved, Transocean Ltd and Halliburton Co, appear before Senate panels probing the disaster.
BP now aims to deploy a small "top hat" dome over the leak after its effort over the weekend to cover it with a huge metal box was stymied by a buildup of crystallized gas hydrates.
Fears of a prolonged environmental and economic disaster for the Gulf Coast are growing after the setback for BP, which contracted the Deepwater Horizon drilling rig that exploded on April 20, killing 11 people and triggering the spill.
Delays in containing the leaking well increase the chances it could become the worst U.S. oil spill, surpassing the 1989 Exxon Valdez disaster in Prince William Sound, Alaska.
The new plan is to have an oil-barrel-sized container at the leak site, a mile down from the water's surface, within 72 hours, BP Chief Executive Tony Hayward said. Then oil would be siphoned up to a tanker.
"There will be less seawater in the smaller dome and therefore less likelihood of hydrate formation," he told reporters at the company's U.S. headquarters in Houston.
Hydrates, essentially slushy methane gas, clogged the top of the dome, preventing crude from being pumped.
The projected westward spread of the massive slick it is creating has raised fears for rich fishery areas filled with shrimps, oysters, crabs and crayfish, and even on major shipping channels off the Louisiana coast.
The company is also spraying chemical dispersants at the ruptured well, an operation Hayward said was showing some success. The well is spewing an estimated 5,000 barrels (210,000 gallons/795,000 liters) of oil a day into the Gulf.
It threatens tourist beaches, wildlife refuges and fishing grounds across four states and has forced President Barack Obama to rethink plans to open more waters to drilling.
Other options BP is weighing to stem the flow of oil include trying to block the well's failed blowout preventer with a "junk shot" of rubber or other materials, or fitting a new valve or preventer. It is also drilling a relief well, but that could still take 75 to 80 days to complete.
In written testimony for Tuesday's Senate hearings, a BP executive directs blame for the blowout at Transocean, the rig's owner and overseer of the operation of the blowout preventer, a stack of pipes and valves designed to close off the flow of oil in case of a sudden pressure change.
Transocean says the blowout preventer was not the cause, and instead points to failure of two other vital elements -- the well's metal casing and the cement that entombed it.
Halliburton, which had the cementing contract, had finished cementing the final casing in place 20 hours before the explosion, according to testimony.
BP has incurred $350 million in costs so far from response, containment, relief well drilling and payments to Gulf Coast states, suggesting the final bill could be much higher than many analysts predicted.
Hayward said an investigation into the incident will reveal what happened in the moments before the well blew out. It will likely also generate new measures to control blowouts.
He rejected the notion that BP, one of the world's largest oil companies, was ill-prepared to deal with such an incident.
"Frankly, it's been far more effective than any spill response hitherto in terms of containment offshore and preventing oil from getting to the shore," he said.
BP shares fell 0.9 percent at 1430 GMT, lagging a 4.8 percent rise in the STOXX Europe 600 Oil and Gas index. The stock dropped as low as 540.7p in London, its lowest level since November. BP's American Depositary Receipts fell 0.5 percent in New York.
The stock has fallen by around 15 percent since the rig blast, wiping around $30 billion from BP's market value.
The Louisiana Offshore Oil Port (LOOP), the nation's only deepwater oil terminal located southwest of New Orleans, said vessel movements were unaffected so far.
The slick's major contact with the shoreline so far has been in the unpopulated Chandeleur Islands off Louisiana, which is a mostly a wildlife reserve and bird sanctuary. At Breton Island in the Chandeleurs, crude is washing into a bird colony, said John Andrew, regional wildlife refuge chief for the U.S. Fish and Wildlife Service.
"I am expecting it to get bad," he said. "The birds are foraging into the water, into the sheen. They plunge for fish. Sheen is getting into their feathers and we are concerned about what happens when they return to the nest."
STATES OF EMERGENCY
The National Oceanic and Atmospheric Administration said winds could push oil ashore in the Mississippi Delta, Breton Sound, the Chandeleur Islands and areas directly north. If the wind keeps blowing from the southeast, oil could reach as far west as Atchafalaya Bay by late on Wednesday, NOAA said.
The two Louisiana parishes directly west of the Mississippi Delta declared states of emergency on Sunday.
National Guard helicopters in Louisiana's Lafourche Parish dropped sandbags onto outlying island beaches to try to block oil from getting into fragile marshlands.
Tar balls washed up on Alabama's Dauphin Island, a barrier island and popular beach resort, during the weekend and local tourism operators said vacation traffic had already slowed to a trickle because of fears of the spill's impact.
"It makes me so sad. You take so many things for granted: a beautiful beach, fresh shrimp whenever you want it. It is so frustrating because there seems to be no answers for it," said Dauphin Island resident Joyce Carroll.
Fishing is suspended in parts of the Gulf waters and much of the Louisiana coast. Many tourists have been scared away by reports of reddish, putrid water offshore, even though the coast is currently unaffected.
(Additional reporting by Anna Driver and Chris Baltimore in Houston; Pascal Fletcher in Miami; Kelli Dugan and Verna Gates in Mobile, Alabama; Steve Gorman and Verna Gates on Dauphin Island, Alabama; Tom Bergin in London; Haitham Haddadin in New York; Writing by Pascal Fletcher and Jeffery Jones; Editing by Ed Stoddard and Eric Walsh)