BP hits snag with containment dome

BP has reported amajor setback with the containment dome that's supposed to collect most of the oil gushing from a damaged pipe in the Gulf of Mexico after ice-like crystals clogged the steel and concrete box.

"I wouldn't say it's failed yet," BP chief operating officer DougSuttles said Saturday. "What I would say is what we attempted to do last night didn't work."

The company lowered the structure to the sea floor Friday evening and began to place it over the source of the environmentally devastating leak.

Since then, a "large volume of hydrates," material similar to ice crystals, has formed inside the box, Suttles said Saturday.

The hydrates which are formed when gas combines with water under certain pressure and temperatures have plugged an area at the top of the dome's interior.

"As we've stressed numerous times this particular operation has never been done at this depth, and we also shared that the big technical challenge was with hydrate formation," Suttles said.

"A large volume of hydrates formed inside the top of the dome, requiring us to move the dome to the side of the leak point. The dome is currently sitting on the seabed while we evaluate options to deal with the hydrate issue."

BP will spend the next two days to troubleshoot the problem, he added, and isstill looking at other ways to control and ultimately stop the flow. BP is also continuing to drill a relief well to reduce the pressure from the blown-out well.

The cofferdam is designed to trap the oil gushing out of one of two leaks from the undersea well and suck it up like a vacuum to a tanker on the water's surface.

The structure, which looks something like a milk carton, is seven metres long, four metres wide and 12 metres tall, with a dome-like roof inside it.

Oil giant BP, which is in charge of the cleanup, hopes it will collect as much as 85 per cent of the almost 800,000 litres of crude that have been gushing out of the well daily for the last two weeks.

The leak is one of three that opened after the Deepwater Horizon oil rig leased by the multinational petroleum company exploded April 20, killing 11 people. The rig sank two days later 80 kilometres off the coast of Louisiana.