A group under the aegis of the Environmental Council has been considering how to dispose of Britain's expanding stockpile of reactor-grade plutonium. It explored four options: immobilisation in an existing or new plant, or burning it as MOX fuel in new or existing reactors. None found universal favour.
BNFL had proposed building two Westinghouse AP1000 reactors at Sellafield to burn 100% MOX fuel, which would consume all the plutonium over 20 years. The resultant spent fuel would be considered to be an immobilised plutonium product and treated as waste.
The UK civil stockpile is approaching 70t.