The Shetland Oil Disaster: Torrey Canyon highlighted the hazards of oil at sea

THE TORREY CANYON disaster in 1967, which resulted in the release of 30,000 tons of oil in a 35-mile-long slick off Cornwall, remains Britain's worst oil pollution disaster. It was also the first big oil spill to illustrate the huge environmental hazards of moving millions of gallons of oil at sea.

The Torrey Canyon, laden with Kuwaiti crude oil, ran at a speed of 16 knots on to the Seven Stones reef west of Land's End. Harold Wilson, the then Prime Minister, watched as Royal Navy aircraft bombed the stricken tanker in an attempt to set its oil on fire and so prevent further spillage. One senior government scientist said at the time that the Torrey Canyon created 'an oil pollution problem of unparalleled magnitude'.

Three years later, in 1970, the tanker Pacific Glory released 3,500 tons of oil into British waters, although a much larger disaster was narrowly averted due to the ship being saved.

In 1976, the Argo Merchant tanker sank off Nantucket, Massachusetts, creating a slick 100 miles long and 60 miles wide. Stormy weather helped to break it up.

A Norwegian tanker, Eleni V, sank off Britain's east coast in 1978 spilling 5,000 tons of oil, affecting beaches in Norfolk and Suffolk. In the same year, the Amoco Cadiz discharged 223,000 tons of crude oil that polluted 300 km (186 miles) of the Brittany coastline - resulting in huge legal claims for damages.

In 1979, a collision between two supertankers - the Atlantic Empress and the Aegean Captain - off the coast of Tobago caused the biggest spill in history with the release of 1.2 million barrels of oil.

Eleven years ago, the Shetlands suffered what was until now its worst oil pollution incident when the tanker Esso Bernicia ran aground in Sullom Voe, site of the islands' then newly opened oil terminal. The spill severely damaged local populations of seabirds.

In the early 1980s there was a decline in the number of tanker accidents but then, in 1987, the Exxon Valdez ran aground off Alaska, releasing more than 240,000 barrels. The environmental damage was extensive. Esso said that up until the end of 1990 it had spent about dollars 2.5bn on its clean-up operation alone. This figure does not include the dollars 1.5bn paid out by insurers or the company's extensive fines.

More recently, a vast spillage occurred off the coast of Morocco from the Iranian tanker Kharg 5. The slick covered an area of about 100 square miles (259 sq km) but bad weather averted a large-scale disaster by dispersing the oil.

In 1990, 7,600 barrels of oil spilled from the tanker American Trader off the coast of California and in the same year the Liberian tanker Rosebay discharged 1,000 tons of oil off the coast of Britain.

Firefighters and rescue teams averted a big disaster in the Gulf of Mexico in June 1990 when the Norwegian tanker, the Mega Borg, was in flames carrying three times as much oil as the Exxon Valdez.

In December 1992, the tanker Aegean Sea, carrying 24 million gallons of oil, hit rocks off the Spanish port of La Coruna and burst into flames. The resulting slick polluted 50 miles of coast.