New figures show three out of every five jobs in Copeland depend on the nuclear industry.
A report by Oxford Economics states that a majority of jobs in west Cumbria are reliant on the presence of Sellafield which is going through the process of decommissioning.
And it has been published as the promise of 20,000 new jobs at a new nuclear facility comes under threat.
The South Korean power company, Kepco, that was expected to take over the NuGen consortium that runs the Moorside development, has lost its 'preferred bidder' status.
According to Reuters news agency, current owners Toshiba will now look at other options for the 15 billion pounds nuclear new-build next to Sellafield.
MPs from both sides of the political divide say the government must act to guarantee the future of the Moorside nuclear site, after talks between Kepco and Toshiba stalled.
NuGen is now in the last chance saloon. The Government must act now or it will be too late, and West Cumbria will not get the 20,000 jobs, economic investment and infrastructure improvements that depend on Moorside."