Characterisation and disposability assessment of multi-waste stream in-container vitrified products for higher activity radioactive waste

Materials from GeoMelt® In-Container Vitrification (ICV)™ of simulant UK nuclear wastes were characterised to understand the partitioning of elements, including inactive surrogates for radionuclide species of interest, within the heterogeneous products. Aqueous durability analysis was performed to assess the potential disposability of the resulting wasteforms. The vitrification trial aimed to immobilise a variety of simulant legacy waste streams representative of decommissioning operations in the UK, including plutonium contaminated material, Magnox sludges and ion-exchange materials, which were vitrified upon the addition of glass forming additives. Two trials with different wastes were characterised, with the resultant vitreous wasteforms comprising olivine and pyroxene crystalline minerals within glassy matrices. Plutonium surrogate elements were immobilised within the glassy fraction rather than partitioning into crystalline phases. All vitrified products exhibited comparable or improved durability to existing UK high level waste vitrified nuclear wasteforms over a 28 day period

Environmental impacts of first Soviet nuclear complex

The first Soviet Nuclear Complex (now the Production Association “Mayak”) was created in the late forties as a key part of the Soviet nuclear weapons program for breeding of weapon grade plutonium and reprocessing of fuel elements. Production during the early years at Mayak lead to heavy radioactive contamination of the nearby territory. In addition to this contamination there are problems associated with the huge amounts of radioactive waste accumulated at the Mayak site. During the Soviet period the Mayak site was restricted area. Outside access was controlled and the facilities were not mentioned in the press or in the literature. Now the legacy of the past fifty years is the focus of both national and international attention. International Institute for Applied System Analysis (IIASA) has conducted the project “Mayak Case Study” aimed at evaluation of radiation hazards to the public and environment and of the technological and management options for dealing with these hazards. The work was done with the support of US Department of Energy, internal IIASA funds and Alton Jones Foundation. The project report describes the radiation legacy of the first Soviet nuclear complex with main emphasis on the radioactive contamination of the Lake Karachay and the Techa River Cascade of Reservoirs. In addition to description of the radiological situation some results of modelling of future threats are presented. Recommendation for future countermeasures both technical and social are presented and discussed