A COURT has imposed a £12,000 fine because thousands of litres of oil containing a pollutant chemical leaked into the sea from Hinkley Point B power station.

British Energy Generation Ltd pleaded guilty at Bridgwater Magistrates Court to causing polluting matter to enter controlled waters two years ago.

Up to 5,000 litres of oil containing a man-made chemical, polychlorinated biphenols (PCBs), had escaped from the power plant's heat exchangers.

Magistrates were told that these heat exchangers used sea water to cool the oil used in the plant's generator and the cause of the leak was traced to corroded tubes.

This allowed oil to escape into the sea water coolant and to Bridgwater Bay, which is a renowned nature site as well as a Site of Special Scientific Interest that is protected under the EU Habitats Directive.

No radioactivity was released, but the PCBs in the escaped oil do not degrade once out in the environment and are listed under the Dangerous Substances Directive.

They contain properties of stability at high temperatures, inertness and flame resistance which are useful but also environmentally damaging.

PCBs tend to accumulate in the fatty tissue of animals and humans and their use is about to be phased out.

The incident was reported to the Environment Agency by British Energy on October 12, 1998.

Ian Myers, for the Environment Agency, said: "Throughout this process, British Energy has displayed a responsible and co-operative attitude.

"However, the events leading up to this incident undoubtedly caused the discharge of an extremely serious contaminant into an important habitat."

British Energy was fined £12,000 and ordered to pay £1,474 costs.

The magistrates said they had taken into account the company's good record in relation to environmental matters, its co-operation with the Environment Agency, the steps taken to remedy the problem, the fact that there was no damage to the environment and that it was an isolated incident.

After the court case, a spokesman for Hinkley Point B said a three-year plan had been implement after the incident to update all management systems at a cost of £1.49 million.