Supporting the war effort
The Sellafield site has been operational since the 1940s, when it was used as a Royal Ordinance Factory supporting the war effort and the National Defence Programme. The factory was constructed to inspect and package small arms ammunition.
In September 1947, the site was announced as the new atomic energy site and work began on the construction of the Windscale Piles and its two air cooled reactors.
By March 1952 the Windscale reactors were in operation producing plutonium for military purposes. These were distinguished by their very tall chimneys. In the same year the first active operation of a plant to separate uranium and plutonium from the used fuel from the Windscale reactors became operational.