A bid to develop the Beacon museum in Whitehaven has been submitted by Copeland Borough Council.
Councillors say the development, that would cost an estimated £1.2 million, would benefit the economy in West Cumbria.
The museum was re-opened this spring after Sellafield agreed to pay for its running costs for the next five years.
Elaine Woodburn, Leader of Copeland Borough Council, said:
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