Calder Hall in Cumbria was opened by the Queen in 1956

Calder Hall in Cumbria was opened by the Queen in 1956, but ceased operating in 2003 after almost 50 years.

Its four cooling towers are due to be demolished on Saturday in a programme to decommission ageing nuclear sites.

The Nuclear Decommissioning Authority (NDA) says a proposed museum has now been ruled out because of the cost.

The NDA had been considering preserving one of Calder Hall's reactors and using it as the basis for a state-of-the-art visitor attraction.

Significant support

The ambitious plan for a museum was seen as a way of enhancing the visitor centre which already exists at Sellafield.

But a study, commissioned by the NDA and carried out by Surrey-based consultancy Atkins, said the project would cost at least �128m.

The NDA has been unable to gather significant support for the project from the private sector or local authorities in the area.

A spokesman for the NDA said: "A feasibility study found that preserving Calder Hall Reactor 1 and creating a museum on the site was possible.

"But the cost involved would be significant, with estimates putting it at around �128m.

"Given the NDA's priorities of tackling high hazards and decommissioning, alternative funding would need to be identified for this project to progress."