EURAD SoK Document - HLW/SF Container (Domain3.2.1)

The aim of this report is to summarise the current state-of-knowledge of all aspects of the selection, design, fabrication, long-term performance and lifetime prediction of containers envisaged for the disposal of radioactive materials in deep underground repositories (or geological disposal facilities, GDFs). In doing so, it has been necessary to be selective in covering the wide range of studies that have been conducted since the mid-1970s. The scope covered in this document is thus limited to a discussion of containers for the disposal of heat-generating high-level waste (HLW) and spent fuels (SF), and excludes the variety of container designs proposed for less radioactive wastes, such as intermediate level waste (ILW). Furthermore, the discussion is limited to conventional engineering alloys, and excludes the use of ceramics (either as coatings or as a bulk container material) or of advanced alloys and coatings. Thus, the main container materials considered here are copper, carbon steel, and some passive alloys (specifically titanium and nickel alloys). Copper coatings applied to a carbon steel or cast iron substrate are also described. In terms of the nature of the repository, the main focus is on ‘deep’ (>200-300 m depth) repositories located below the water table in either saturated, anoxic (crystalline or sedimentary) host rock formations or in dry salt formations. Relevant information from programmes considering disposal in unsaturated host rock is also included.