Decommissioning planning for the Joint European Torus Fusion Reactor

The Joint European Torus (JET) machine is an experimental nuclear fusion device built in the United Kingdom by a European consortium. Tritium was first introduced into the Torus as a fuel in 1991 and it is estimated that at the end of operations and following a period of tritium recovery there will be 2 grams of tritium in the vacuum circuit. All in-vessel items are also contaminated with beryllium and the structure of the machine is neutron activated. Decommissioning of the facility will commence immediately JET operations cease and the UKAEA's plan is to remove all the facilities and to landscape the site within 10 years. The decommissioning plan has been through a number of revisions since 1995 that have refined the detail, timescales and costs. The latest 2005 revision of the decommissioning plan highlighted the need to clarify the size reduction and packaging requirements for the ILW and LLW. Following a competitive tender exercise, a contract was placed by UKAEA with NUKEM Limited to undertake a review of the waste estimates and to produce a concept design for the planned size reduction and packaging facilities. The study demonstrated the benefit of refining decommissioning planning by increasing the detail as the decommissioning date approaches. It also showed how a review of decommissioning plans by independent personnel can explore alternative strategies and result in improved methodologies and estimates of cost and time. This paper aims to describe this part of the decommissioning planning process and draw technical and procedural conclusions. (authors)