A NEW scheme has been launched to prevent a concrete reservoir at a nuclear site with the capacity to hold a million gallons of water from collapse.

Blacknoll Hill underground reservoir is set to be decommissioned under new proposals which have been submitted to Purbeck District Council by Magnox.

The project is one of the biggest steps as part of the ongoing decommissioning of the former Winfrith nuclear power station by Magnox Ltd, who currently manages the western half of the former power station site on behalf of the Nuclear Decommissioning Authority.

The Blacknoll reservoir consists of a 126ft by 96ft reinforced concrete tank sunk approximately 17ft below the surface near to the top of Blacknoll Hill with the roof of the reservoir being supported by 28 steel reinforced columns and an internal wall running along its length.

Its purpose when it was built in 1960 was as a source of softened water supply for site operations and as a source of water in the event emergency cooling was required at one of the reactor plants throughout Winfrith operations.

In a planning document by Hayrock on behalf of Magnox, said: “Structurally, the reservoir is in good condition; however, deterioration could lead to the eventual collapse of the structure if it was abandoned.”

The decommissioning will consist of a number of steps with each completed before the next step commences.

Under the proposals, the first stage will see vegetation clearance and earth roof cover removal to gain access to the reservoir followed by the demolition of reservoir roof, walls, columns and central wall and associated features including the valve house.

The concrete approach road will then removed and used as backfill to help restore the landscape.

Magnox has also put in place mitigation strategies to ensure minimal impact to the environment and surrounding sies when HGVs travel to and from the site.”

The report added: “It has been demonstrated that even during the most intensive stages of work, the site would generate minimal traffic flows and vehicles associated with the site would be unlikely to pass on Gatemore Road.

“The proposals would not have a material impact on safety or a severe impact on the operation of the highway network.

“In addition, due to the low vehicle generation and temporary, short-term nature of the project, it is considered the project would have a negligible and not significant environmental effect in relation to transport. “

The process of decommissioning will begin in September 2018 and will last for two months.