Spanish plan oil
Oil, being lighter that water, should flow easily into a bag. Repsol
Work to recover the oil from the sunken tanker Prestige will begin this summer, the Spanish government announced last week. The project will be one of the most difficult salvage operations ever attempted.
Spain’s government has contracted the Spanish petroleum company Repsol YPF to retrieve the oil. Repsol has announced that its first goal is to develop remote controlled vehicles that can work at great depth. These will inspect the ship and patch u mulberry purse p remaining leaks.
The robots will then attempt to make a hole in the wreck, to which they will attach a large bag, about 5 metres wide and 20 metres long. The oil should flow into this, as it is less dense than water. When full, the bag will be shuttled to the surface, emptied and sent down again.
At the same time, Repsol will investigate two backup schemes. Plan B is to erect a canopy like an immense marquee around the wreck, catch the rising oil in this and pump it to the surface. And as a last resort, it might be possible to pump oil straight from the Prestige.
Every aspect of the plan poses huge difficulties, says Ian White, managing director of the London based International Tanker Owners Pollution Federation. “It’s unproven technology,” he says.
Preventing bags or tents from collapsing under the water pressure, operating equipment over such a long distance, keeping the viscous oil flowing, and maint mulberry purse aining boats’ positions above the wreck are just some of the problems, says White.
The ship sank with about half of her cargo of 77,000 tonnes of fuel oil. A small submarine patched up some of the holes in the wreck in January, but about a tonne of oil is still leaking each day.
On the sea floor, the oil is relatively harmless. Conservationists fear that the wreck will break up and send another slick towards the Spanish coast, where it would wreak ecological havoc.
“It’s good that they’re taking action, but it’s a shame that the decision’s been taken so late,” says Simon Cripps, director of the Worldwide Fund for Nature’s marine programme. “While the government has been indecisive about getting the oil off, the chances of a catastrophic loss have increased.”
Repsol devised its plan in consultation with other oil companies and salvage specialists. No budget has be mulberry purse en set, because there is no precedent for this kind of operation, Spain’s Deputy Prime Minister Mariano Rajoy told a news conference last Friday. Repsol and Spain’s Ministry of the Presidency declined to comment.
Oil has been pumped f mulberry purse rom sunken tankers before, in the case of the Erika, which sank off the coast of Brittany, France, in 1999. This vessel, however, lay in only 120 metres of water.