SUFFOLK’S nuclear power station should be back on-line by the end of the month, energy bosses confirmed last night.

The reactor at Sizewell B has been shut down since March because higher than normal moisture levels were detected in a containment building.

Last night owners EDF Energy said repairs were going well and they expected service to resume shortly.

The original problem was caused by one of the heaters associated with a component known as the pressuriser.

The final stage of repair work is now under way and bosses are confident the reactor will be up and running by the end of the month.

Jim Crawford, Sizewell B station director, said: “The mechanically failed heaters have been removed from the pressuriser and repairs are being finalised.

“The confined space the engineers had to work in made this a challenging operation. However, the expertise within the team working on this project and the extensive tests carried out on the replica equipment ensured this ran smoothly.”

Fuel has been removed from the reactor and placed in a storage pond until the repairs are complete.

Experts from Europe and America were flown in to help complete the work, while electronic remote equipment and video footage was also used.

Bosses said they have had a total loss of generation in the range of 4TWh to 6TWh. However, they have refused to say how much the closure has cost in monetary terms, although it is estimated to run into tens of millions of pounds.

The Health and Safety Executive and the Environment Agency have said they are satisfied with Sizewell’s response.