After three days of blasting mud and other materials into the well, oil giant BP said that engineers had been unable to stop oil from spewing into the ocean. (photo, from aljazeera.net)
On Saturday, Doug Suttles, the company’s chief operating officer, told reporters that it is time to “move on” and try other solutions.
BP’s latest effort to plug the broken wellhead in the Gulf of Mexico was the so called “top kill” operation. It had pumped around 4.5 million litres of mud into the gushing well, but most of it escaped out of the well’s damaged riser pipe.
“After three full days of attempting top kill we have been unable to overcome the flow from the well so we now believe it’s time move on to the next options,” Suttles said.
Six weeks ago an explosion hit BP’s Deepwater Horizon drilling rig, killing 11 workers. Since then, the leaking well has spewed some 68 million litres of oil into the Gulf of Mexico.
The spill is the worst in US history – exceeding even the Exxon Valdez disaster in 1989 off the Alaska coast.
So far, BP has spent $940m to try to plug the leak and clean up the sea and soiled coast.
“This scares everybody, the fact that we can’t make this well stop flowing, the fact that we haven’t succeeded so far,” Suttles said.
“Many of the things we’re trying have been done on the surface before, but have never been tried at 5,000 feet.”
In the coastal fishing communities of the US state of Louisiana, disapointment met the news that the top kill attempt had failed. It is there that oil first made landfall in large quantities almost two weeks ago.
“Everybody’s starting to realise this summer’s lost. And our whole lifestyle might be lost,” Michael Ballay, manager of the Cypress Cove Marina in the town of Venice, told the Associated Press.
The top kill operation was the latest of several failed attempts to plug the leaking well.
In the days following the explosion, BP engineers tried to use robot submarines in order to close valves on the massive blowout preventer atop the damaged well.
Two weeks later the company tried to place a 100-ton containment box over the leak, but ice-like crystals clogged it and it had to be removed.
And earlier this week engineers removed a mile-long siphon tube from the broken riser pipe after managed to extract a disappointing 3.4 million litres of oil from the well.
Pressure is growing on BP to do more to contain the leak.
Suttles said engineers are already preparing for the next attempt which would use robot submarines to cut off the damaged riser from which the oil is leaking.
Then they would try to cap it with a containment valve in an operation that is expected to take between four and seven days.
“We’re confident the job will work but obviously we can’t guarantee success,” Suttles said.
He added that cutting off the damaged riser was not expected to cause the flow rate of leaking oil to increase significantly.
But other experts have warned that the operation is risky because a bend in the damaged riser pipe was likely to be restricting the flow of oil.
“If they can’t get that valve on, things will get much worse,” Philip W. Johnson, an engineering professor at the University of Alabama, told the Associated Press.
“It’s a scary proposition.”
A permanent solution to the leak, a relief well currently being drilled, will not be ready until August, said BP engineers.
(map, from bbcimg.co.uk)