Ambitious project to bring up sunken oil

By CATHERINE FIELD Herald correspondent

PARIS - All eyes on the Breton coast have turned to the sky in supplication, hoping that the weather gods will smile on a perilous operation to salvage oil from the remains of a shipwrecked tanker.

The elderly, ill-starred Erika foundered in strong storms last December. It broke into two halves, spewing between 10,000 and 15,000 tonnes of fuel oil into the sea, fouling 450km of coastline, including some of France's finest holiday beaches.

Now an unprecedented $160 million operation has been launched to recover up to 15,000 tonnes of oil holed up in the fore and stern sections of the ship.

A taskforce of experts from three countries this week began orchestrating a small fleet of ships and squads of divers, using technology that has never been tested on this scale before, with the goal of removing the oil before autumn gales set in. Two giant British-owned diving support ships, the Seaway Kestrell and the CSO Constructor, have each taken up position over the two sections, which are resting on sand at a depth of 120m, 10km apart, about 70km south of Penmarch, on the western Brittany coast.

Each vessel has a team of nine divers, divided into three teams, who have the unenviable task over the next four months of working five or six hours per day in the Stygian gloom of the eastern Atlantic. After their shift is over, the divers will be hauled back up to the ship, where they will be immediately confined to 18 sq m compression cabins that will keep their ambient air pressure at 10 times that at sea level. A team of 15 people are on call to provide food and drink and monitor air supply and humidity. Any exposure to ordinary atmospheric pressure will quickly kill the divers from the bends.

Escorted by robot submarines, the divers will drill holes in the tanker's sides and install dozens of valves, an operation that at these depths carries huge risks of a catastrophic breach.

An anti-pollution ship, British Shield, equipped with floating barriers and dispersant, has been positioned nearby, together with a flotilla of escort vessels to tackle any spill. The first wave of oil last year killed tens of thousand of birds and ruined prospects for the local tourist industry.

The divers will then prepare the operation's secret weapon: tanks containing a derivative of rapeseed oil called methylated colza ester which will be set down on the seabed and hooked up to the valves.

The idea, according Coflexip-Stolt, a Franco-Norwegian salvage consortium, is to mix the fuel oil, which at these chilly temperatures has the consistency of squidgy ice cream, with a small per cent of rapeseed oil, which is light and runny. The mixture should then be fluid enough to be pumped up to the surface to an awaiting tanker, which will transport it to a refinery for separation or burning.

"In theory, we shouldn't encounter overwhelming problems," says Jean-Pierre Van Til, project engineer with the Franco-Belgian oil giant TotalFina-Elf, which chartered the 25-year-old Erika and is picking up the salvage tab.

"All the equipment and pumping operations have been tested, and so has the oil fluidifier. If the weather turns bad, the ships can disconnect from the flexible hoses leading down to the tanker and find shelter. They can find the spot again, thanks to satellite navigation and acoustic beacons placed on the sea bottom."

Others are worried about all the smaller things that could go wrong, the "human errors," accidents and breakdowns that could cause an accumulative delay, wrecking an operation choreographed to unfold at two sites at the same time.

"The trickiest thing is not the scale of the operation, but the very tight schedule," says Tom Fell, project spokesman. "Everything has to be done in parallel."