U.S. counts on BP to stop leak, less oil siphoned off

VENICE, Louisiana (Reuters) - The U.S. government is forced to rely on BP and the private oil sector to try to plug the gushing Gulf of Mexico well because only they have the technical know-how to stop the spill at those depths, the U.S. Coast Guard chief said on Sunday.

The admission by Admiral Thad Allen, who heads the oil spill response operation, came as BP said the current containment method it was attempting on the ocean floor was capturing much less of the leaking oil than three days ago.

Company engineers were readying other short-term solutions, the next one expected to start late on Tuesday. But BP Managing Director Bob Dudley said there was "no certainty" of success at the unprecedented depths at which they were being tried -- one mile (1.6 km) down in the Gulf of Mexico.

More than a month after a rig explosion triggered what President Barack Obama has described as an environmental disaster and "BP's mess," oil is still spewing unchecked from BP's ruptured Macondo seabed well.

At a time of mounting U.S. government and public criticism of the company and its executives over the catastrophic spill, Allen said he trusted BP Chief Executive Tony Hayward, who has made comments downplaying its size and environmental impact.

Sheets of heavy oil have washed ashore in Louisiana's fragile marshlands and lesser "oil debris" has also reached the coasts of Mississippi and Alabama in what is seen as an ecological and economic calamity for the U.S. Gulf Coast.

Given the lack of a solution so far and the doubts over BP, Allen was asked on CNN's "State of the Union" show on Sunday why the U.S. federal government did not completely take over the spill containment operation from the London-based firm.

"What makes this an unprecedented anomalous event is access to the discharge site is controlled by the technology that was used for the drilling, which is owned by the private sector," Allen said. "They have the eyes and ears that are down there. They are necessarily the modality by which this is going to get solved," he added.

Asked too about the apparent growing U.S. lack of confidence in BP CEO Hayward, Allen said: "I trust Tony Hayward. When I talk to him, I get an answer".

INSERTED TUBE CAPTURING LESS OIL

BP has deployed a long suction tube down to the larger of two leaks from the well, but a BP spokesman said on Sunday this captured only 1,360 barrels per day of oil over the 24 hours to midnight Saturday. The flow has been declining from the 5,000 barrels (210,000 gallons/795,000 litres) per day the company had said the tube was siphoning off three days ago.

BP engineers are now preparing a "top kill," pumping heavy fluids into the well to try to shut it off, an operation to begin late Tuesday or early Wednesday, Dudley told CNN.

Other possible short-term options include a "junk shot" of pieces of rubber and other materials into the failed blowout preventer on top of the leaking well. Allen added another option was the fitting of a new blowout preventer.

Dudley said BP would press ahead with all of these while also drilling a relief well -- widely viewed as the plugging option with the best chance of success -- expected to be finished in August. "We will keep trying, we will not wait until August," Dudley told CNN.

The Coast Guard's Allen compared the battle to contain the spill and its spreading slick to "fighting a multi-front war".

He added that when the leak was finally sealed, the total oil spilt would "probably start to approach" the 1989 Exxon Valdez accident in Alaska, the worst U.S. spill. The tanker accident spilt 11 million gallons (41 million litres) .

But many scientists believe the Gulf spill has already eclipsed this, and warn the spreading oil could increasingly be caught in a powerful ocean current that could take it to the Florida Keys, Cuba and the U.S. East Coast.

One marine scientist said that to figure out how much oil has spilt into the Gulf, experts should measure the plumes of dissolved methane coming from the blown well.

Iran, a fierce critic of Washington, repeated an offer to assist with the Gulf accident, calling it no great challenge compared to its own past oil spills.

PRAYERS TO GOD

Churchgoers in Louisiana coastal parishes affected by the spill prayed for God's help. "You (God) can clear that oil up, because that oil was down there thousands of years before it came up in the Gulf. So you know what to do with it, dear God," retired oyster fisherman Herbert Guidry prayed in the New Mount Pilgrim Baptist Church in Houma.

Obama at the weekend formally established a commission to investigate the disaster and also made his first reference to the possibility of a criminal probe. But he is facing increasing pressure to do more to solve the problem.

"Almost a month and a half later, and it's still spilling oil ... Right now, the federal government is not moving forward on BP and cleaning up that mess," Republican National Committee Chairman Michael Steele told ABC's "This Week".

White House spokesman Robert Gibbs said: "We have mobilized every aspect that we possibly can in our government." He told CBS's "Face the Nation" there had been some problems with what he called "BP's lack of transparency."

Obama said U.S. offshore drilling could go forward only with assurances that such accidents would not happen again.

Analysts say growing ecological and economic damage from the spill could become a political liability for him before November congressional elections.

While also promising to hold Washington accountable for proper oversight of the industry, Obama ramped up pressure on companies linked to the spill: BP, Halliburton and Transocean Ltd. He believed a "breakdown of responsibility" between them led to the disaster.

BP stocks have taken a beating in the markets in the month since the well blowout and rig explosion that killed 11 workers and touched off the spill. Its share price shed another 4 percent on Friday in London, extending recent sharp losses.

(Additional reporting by Susan Heavey and Jackie Frank in Washington, Sharon Reich in Louisiana, Hashem Kalantari in Tehran; Writing by Pascal Fletcher; Editing by Jackie Frank)