Development of a transport container to transport high level waste and spent fuel to a Geological Disposal Facility in the UK

Radioactive Waste Management (RWM) is responsible for developing a Geological Disposal Facility (GDF) for UK's higher activity waste. RWM are developing concepts for a range of Disposal Containers for the geological disposal of high level waste and spent fuel. In support of this, International Nuclear Services Ltd (INS) is working with RWM to develop a concept for a transport container to transport the Disposal Containers to a GDF. This design of transport container is named the Disposal Container Transport Container (DCTC). Initial studies carried out by INS optimised the container geometry and established the use of Multiple Water Barriers (MWB) as the preferred option to achieve criticality safety requirements for transport. Further development has focussed on detailed impact, thermal and shielding assessments and how this influenced the DCTC mass. These findings were presented at the 17^th PATRAM conference, San Francisco in 2013. In particular that paper highlighted the challenge of designing a transport container where the contents were 45% of the total package mass limit. As the DCTC design has been developed, so too have the external factors that define the requirements for it. Two factors that have a significant influence are: the developing technologies in the rail industry, resulting in increased payload capacities; and the triennial update of the UK derived inventory which defines the radioactive materials that could be transported to and disposed in a GDF. The 2013 inventory update has seen the introduction of additional materials with increased shielding, thermal and mass requirements, further challenging the overall mass limit. This paper discusses how the DCTC has progressed to its current stage; how it is influenced by the associated rail wagon concept and sets out the opportunities that have been identified jointly by INS and RWM to address the challenges presented by the expanded scope of the derived inventory. It also gives detail on how these opportunities can be incorporated in order for the DCTC design to meet the International Atomic Energy Agency (IAEA) regulatory requirements. (author)