Position Paper

A review For many years there has been a sustained international interest in partitioning and transmutation of the minor actinides neptunium, americium and curium produced by fission reactors. Although these three elements are produced in relatively small quantities in fission reactors, they are major contributors to the decay heat, neutron output and radiotoxicity of spent nuclear fuel. If spent nuclear fuel is reprocessed conventionally, the heat output, neutron output and radiotoxicity from the minor actinides carries over to the vitrified high level waste (VLHW) in which they are incorporated. Partitioning involves modifying reprocessing operations so that the minor actinides are partitioned in a separate chemical stream, or perhaps a stream comprising a mix of minor actinides combined with plutonium. Subsequently, they could either be stored or returned into the strong neutron flux of a reactor to be transmuted by fissions. Actinide transmutation would greatly reduce the mass of minor actinides in the geological repository and potentially increase the effective capacity of a geological repository and/or reduce its future environmental and radiological impacts