THE risk of any nuclear fuel flasks leaving Oldbury power station with radioactive contamination on them has been lowered as a result of significant improvements being made.

Last summer it was revealed that contaminated debris was found on a rail wagon used to carry flasks of spent fuel from the plant.

The small metallic fragments were discovered when the wagon was monitored on arrival at the Sellafield reprocessing site.

It was thought they had been picked up on the feet of a flask when it was in a cooling pond at Oldbury, which no longer generates power and is being decommissioned.

Although the flask had been checked before leaving, the contamination was not detected, possibly because the fragments had become pressed into the flask’s rough feet and were not picked up during monitoring.

The material was only discovered later because it had loosened by the time it reached Sellafield.

The incident resulted in a letter being written to Oldbury by the Office for Nuclear Regulation (ONR) rather than any regulatory action being taken.

But station bosses were warned that any repeat incident could involve a notice of improvement being issued.

Updating the latest meeting of the Oldbury Site Stakeholder Group, Peter Dickenson of the ONR said Oldbury “had made significant improvements in waste management in the pond area” since the incident.

He said: “The potential for the flasks to leave site with contamination is a lot rarer now. It had been low before but is now even lower. The amount of work done is pleasing.”

Oldbury site director Mike Heaton outlined the improvements made, which included a thorough cleaning of the cooling ponds, better monitoring techniques, procedural changes and better lighting.

He said: “It’s been a major focus. All these things have improved standards.”

The flasks of spent fuel are taken by road from Oldbury to the Berkeley railhead before being loaded onto rail wagons and carried to Sellafield.

When the incident was reported, Oldbury’s deputy site director, Rob Ledger, said the wagons were securely locked during shipment and no staff or members of the public were exposed to radiation during transportation.

Defuelling of Oldbury since it was shut down three years ago is still continuing. Mr Heaton said more than 60 per cent of fuel from the site’s two reactors had been removed, with flasks of spent fuel currently being dispatched at the rate of three a week.

There were about 140 flasks still to go and at that rate, the job should be complete this year.

There will then be a period of about six months when areas that could have held fuel at any time will be checked to confirm none remains. Once the regulators are satisfied, the site will then move onto the next step in the decommissioning process.