First cut out of reactor pond wall
February 16, 2017
The first block of concrete has been removed from the structure of one of Dounreay's cooling ponds – representing a major first step in demolishing the redundant giant chamber.
The pond is one of two concrete pits, six metres deep, which was used to store spent fuel from the Dounreay Fast Reactor (DFR). When in operation they resembled deep swimming pools, containing around 500m³ of water, providing shielding for workers from radiation emitted from spent fuel. They have now been drained of water and sludge, while redundant equipment has been removed.
There are around 180 blocks of concrete, individually weighing around one tonne, to be removed from each pond and packaged as waste.
Suzanne Griffiths, Project Manager, said: "Decommissioning of the ponds is technically challenging. While each block is only around 1m², it is extremely heavy and the process of cutting it is complex. The team has worked exceptionally well together and applied lateral thinking, deploying new techniques to allow the concrete liner to be removed in preparation for final demolition."
The work in DFR is one the biggest decommissioning tasks in the UK today. It is one of the highest hazards within the Nuclear Decommissioning Authority’s estate and the safe removal of associated plants and facilities is crucial to getting Dounreay to its interim end state.