Caion, Spain ? Winds reaching 60 mph and high waves hindered shoreline cleanup and seafood farmers scrambled to salvage the cockle, mussel and clam harvest Wednesday, a day after the tanker Prestige and its cargo of fuel oil sank off Spain.

Yet the high winds, which pushed waves to 26 feet, helped break up a large oil slick off Portugal as Spanish authorities worried the storm was shoving a second fuel oil slick closer to the coast.

Seeking to ease fears of an Exxon Valdez-style catastrophe, Spain’s Interior Ministry said no fuel had spilled since the single-hulled vessel broke apart and sank about 150 miles off the Spanish coast Tuesday, six days after it ruptured in a storm. Officials said they hoped the oil would solidify two miles down in frigid water, limiting damage in the short-term.

The Prestige has spilled about 1.6 million of its 20-million gallon load of heavy fuel oil, a total twice the size of the Exxon Valdez crude-oil spill off Alaska in 1989.

Spain said Wednesday it had spotted four oil slicks, including one 10 miles long and 3 miles wide, near the wreckage about 150 miles off the Galician coast.

Two smaller slicks are about 40 miles west of Cape Finisterre, and a third is just off the coast at the Muros inlet, Spanish officials said. Portugal said a large slick it was monitoring Tuesday apparently dispersed in rough seas.

Spanish Environment Minister Jaume Matas said oil has contaminated nearly 180 miles of Galicia’s scenic coastline and rich fishing waters. During a visit to a soiled beach near the fishing port of Caion, he estimated economic losses at $42 million so far, and said the cleanup could take six months.

“We have to wait and be prudent because we still don’t know whether we have passed the threshold of this crisis,” Matas said.

Crews with shovels and buckets worked in strong wind and heavy rain to scoop up sludge along Galicia’s craggy coast. The government said more than 250 tons of fuel oil had been recovered so far, half on land and half at sea by skimmer boats.

Rough seas kept two of the vessels ” sent from France and Holland ” out of the mission Wednesday, the interior ministry said.

In some coastal areas not yet hit by the fuel oil, seafood farmers rushed to harvest mussels, clams and cockles ahead of schedule. Spain’s fishing industry is worth $330 million a year.