OPERATORS of the Sizewell B nuclear power station have been formally cautioned by the UK environment watchdog for failures involving discharges of radioactivity.

By David Green

OPERATORS of the Sizewell B nuclear power station have been formally cautioned by the UK environment watchdog for failures involving discharges of radioactivity.

British Energy has also been handed an enforcement notice while the British Nuclear Group, which runs Sizewell A, has been ordered to make changes to procedures after failing to promptly notifying inspectors about two radiation incidents.

However, the Environment Agency believes the failures did not pose any threat to the environment.

Operators of nuclear power stations are allowed to routinely discharge tiny amounts of radioactivity in liquid and gaseous form.

But the Environment Agency expects procedures to be strictly followed and all regulations observed.

The formal caution for British Energy follows a 21-month long investigation into an incident into the “deficient” operation of filters attached to radioactive effluent pipelines.

The investigation was also into a failure by staff to sample a radioactive isotope called tritium in airborne discharges.

An enforcement notice has also been issued in respect of an error in sampling airborne discharges of another isotope, Carbon 14, over a period of four days.

Sizewell A has been ordered to make procedural changes after leaks from systems involving radioactively contaminated water and sludge.

The Environment Agency was concerned about “unacceptable” delays in notification about the latter problems.

It is also concerned that operator error led to a radioactive gas discharge line not being monitored for six hours.

Dr Paul Naylor, the agency's inspector for the nuclear site, said a warning in respect of the British Energy failures had been considered insufficient because of important departures from good working practices.

“A caution was offered as an alternative to prosecution because neither event had detectable environmental impacts, or the potential for significant impacts, and British Energy responded appropriately to the problems,” he said.

The company has been warned that a court could consider the caution if further offences are committed and a prosecution launched.

Dr Naylor said that although there could have been very small additional discharges of radioactive material to the environment as a result of the incidents at Sizewell A and B, total discharges would still have been within authorised limits.

“The environmental impact would be negligible,” he said.

The agency fixes discharge limits for each radioactive isotope but actual discharges are usually significantly lower.

Under a current review of discharges at the B station, the limits for six radioactive isotopes are likely to be tightened and one limit to remain the same.

Martin Pearce, British Energy spokesman, said better procedures had been developed as a result of the problems experienced. “We accept the caution and will continue to try to strive for the best environmental standards possible,” he added.

There was no-one available to comment on behalf of the British Nuclear Group.

Charles Barnett, chairman of the Shut Down Sizewell Campaign, said: “We believe both stations should have zero discharges which they can achieve although it is expensive.

“If they can't achieve that then the stations should be closed down.”