'Chernobyl of Spain' may haunt waters for decades

In February 2002, a team of investigators discovered that the numerous oil slicks that have long polluted California's coast off San Francisco are due to the vessel Jacob Luckenbach, which sank in July 1953, with 132,000 gallons of heavy fuel oil as cargo.

Although, half a century has passed, the wreckage, resting under 185 feet of water, still constitutes a threat to the environment.

Similarly, the oil tanker Prestige may haunt Spanish waters and the coastline for decades.

The tragedy involving the Prestige started on November 19 when the 26-year-old tanker split in two and sank, 150 miles off the north-west coast of Spain, known as the 'Coast of Death' because of its rocky shoreline where over 300 ships have sunk in the last 100 years.

It was the third oil slick on the Galician coast since the Urquiola sank in 1976 and the Aegean Sea in 1992. However, it is considered to be the most major of the three.

Over a month after the disaster, 1,000 km of the coast, which comprises 1,121 km was covered with oil. More than 800 km was closed to fishing and shellfish gathering.

More than 20,000 tons of fuel oil of the total 77,000 tonnes are estimated to have been released in the water. And, the danger of a larger environmental catastrophe has not been averted.

On the contrary, for many specialists, the Prestige is still an environmental time bomb that could explode any time and oil could surface. The wreck with its over 55,000 tonnes of fuel oil still constitutes a potential danger. In fact, the tanker's hull is not made to withhold the pressure in the depths at 3,500 metres.

Moreover, the European Scientific Committee responsible for evaluating the situation has detected 14 cracks in the hull, which allows 120 to 125 tonnes of fuel to leak every day. At such a rate the Prestige's tank will be drained in 16 months. In such a scenario, the world will be face one of the largest oil spills in history.

While referring to history, the Prestige incident is not new - it is just another accident involving oil. In the 20th century there were more than 200 accidents involving oil tankers, starting with the running aground of the Torrey Canyon in the English Channel in 1967, which resulted in the spillage of 95,000 tonnes of oil.

This was followed in 1978 when the Amoco Cadiz spilt 220,000 tonnes of oil near the French coast. Then in 1979, the collision between the Aegean Captain and the Atlantic Empress in the West Indies resulted in the spillage of more than 287,000 tonnes of oil. The explosion in 1991 of the ABT Summer spilt 260,000 tonnes of oil.

One of the worst oil spills was the Exxon Valdez spill in 1989 on Alaska's southern coast although only 37,000 tons of oil were involved.

The impact of this accident on the environment was catastrophic: an estimated 250,000 seabirds were killed along with 3,000 otters, 300 seals, 250 bald eagles and 22 killer whales.

However, scientists and environmentalists agree that the volume of an oil spill is not the only factor in determining the damage it can cause.

The Prestige disaster is considered the world's 17th worst oil spill according to tonnage lost. Nevertheless, its impact on the environment is expected to be one of the worst.

The location of the oil spill and the nature of the product are generally more significant factors.

Sometimes a small oil spill that occurs in a sensitive location can cause tremendous damage to the environment.

Previous accidents have proven this. The Exxon Valdez, which was carrying 37,000 tonnes of oil, caused greater damage than the Braer that was carrying twice as much oil.

Oil spills in the open ocean tend to have lesser effect than oil that reaches the coastline. In fact, the combination of shallow water and a poor flush of water intensify the impact of an oil slick.

In the open sea the oil spill is more easily dispersed by waves and the weather. The nature of the product can also play an important role - fuel oil can be far more toxic and difficult to clean up than crude oil.

Many environmental organisations feel that the most efficient clean up is by the natural elements such as winds and waves. However, often this solution alone is not sufficient and there is an urgent need to use other methods.

One of the most common is floating barriers to prevent the spill from spreading. This method is complemented by using chemicals or dispersants, which contain surfactants that help break the oil spill into small droplets enabling the oil to disperse into the water more easily.

Biodegradation is another alternative. Scientists have discovered that certain types of bacteria can be very efficient in the cleaning up. By adding some microorganisms and fertilisers this natural process can be accelerated.

Oil can also be burned; fire resistant booms are usually used to collect the oil into a slick to be burned. The most recent technique is a giant sponge made of lignite resin that absorbs the oil, preventing it from spreading in the water. In the case of the Prestige, clean-up operations have been limited by the difficult weather conditions, which have made it an almost impossible mission for the salvage teams.

Some researchers and scientists believe that the recovery of the economy and the environment will take at least 10 years, in a region where the fishing industry's production is nearly $330 million a year.

In some regions of the Galician coast more than 73 per cent of the population is working in the fishery sector. So far, more than 4,000 fishermen have been affected and initial losses are estimated around $42 million. But the impact of the disaster will also hit other sectors such as the food processing industry and tourism.

And, it is still very early to evaluate the real scale of the catastrophe on the region. Moreover, some species will need even 25 years to recover. Around 15,000 seabirds have been killed or covered in oil since the beginning of the disaster. The Spanish public works minister was not exaggerating when he said: 'The Prestige is our Chernobyl'.

To prevent such accidents in the future, the European Union (EU) imposed a ban on the entry of potentially dangerous ships to European ports, especially single hulled tankers carrying heavy oil products.

Nevertheless, as long as the world relies on oil, there will be spills like the Prestige disaster, especially when we know that 60 per cent of the world's oil consumption is carried by sea, and that crude oil provides about 40 per cent of global energy.

The Prestige will most probably not be the last episode in a long series of accidents. Ninety per cent of EU oil imports are delivered by sea, 60 per cent of the tankers used to transport oil are more than 10 years old and 25 per cent are over 20 years old.


Battling against the slicks

The Prestige caused two huge slicks since it sank in the Atlantic, one driven by the wind towards Portugal and Spain, while the other hit the Galician coast in northwest Spain.

Portugal sent an anti-pollution vessel to divert the slick from its coast. The Spanish government contracted a French mini-submarine to seal the tanker. On December 21, the French submersible, the Nautile, managed to block three of the 14 holes discovered so far. The Nautile mainly uses a kind of sandbag to block the leaks.

Fishermen in Spain continued with their battle against the oil slicks using cranes, small nets and sophisticated anti-pollution vessels. France might be joining Spain soon to fight the oil slick, especially since a massive slick was