The demolition of 100 buildings at Sellafield has left five football fields worth of space for the plant to develop.
The work, which began in 2007, is seen by the company as the "closing a significant chapter in Sellafield’s history."
The cooling towers were some of the first buildings to be demolished and the original fire station was the 100th building to be decommissioned.
Over the next century there are over 1,300 facilities at the site which will all need to be decommissioned.
Sellafield say they are prioritising projects where historic buildings are deteriorating and nuclear waste is no longer stored to modern standards.
The programme of work may even stretch to 2120.