The Prestige is lying 3.5 kilometres down on the floor of the Atlantic, some 200 kilometres off the north-west coast of Spain. Oil has never been recovered from a depth of more than two kilometres. The Dutch specialists think it's technically possible, but it will be extremely difficult.
Smit's engineers propose lowering a remotely operated drill and pump onto the Prestige. It will bore a 15-centimetre hole near the top of the hold and connect up a pipe to the surface.
Rapeseed oil will then be pumped down from the surface and mixed with oil from the hold to thin it. The mixture will then be pumped up a second pipe to barges on the surface.
One problem the salvagers will have to cope with is the rough water in the Atlantic. Because of the four to five metre high waves the salvage workers have to use large ships.
The decision on whether or not to salvage the oil is ultimately a political one for the Spanish government, which is being helped in the clean-up effort by a number of other European countries. In economic terms, the oil is not worth recovering. The salvage cost exceeds the value of the oil, but it's cheaper than the cost of cleaning up if the oil escapes.
Source: New Scientist.
