Highly active liquid waste management at Sellafield

Spent nuclear fuel elements from the U.K. nuclear reactor programme are reprocessed at Sellafield by dissolution in aqueous acid solution and chemical separation of the plutonium and unused uranium. The remaining highly active fission product liquid waste, which contains more than 99% of the dissolved fission products activity, together with impurities from the fuel cladding, corrosion products from the chemical separation plant and traces of the plutonium, uranium and transuranic elements is termed the Highly Active (HA) liquid waste. The present HA liquid evaporation and storage systems are described together with the future policy and plant design for vitrification, storage of the vitrified HA waste and proposals for ultimate disposal of these wastes. (U.K.)