Mobility of radionuclides

Bischoff JL, Fitzpatrick JA (1991) U-series dating of impure carbonates An isochron technique using total-sample dissolution. Geochim Cosmochim Acta 55 543-554 Bonotto DM (1998) Implication of groundwater weathered profile interactions to the mobilization of radionuclides. J South Am Earth Sci 11 389-405... 

Askbrant S, Melin J, Sandalls J, et al. 1996. Mobility of radionuclides in undisturbed and cultivated soils in Ukraine, Belarus and Russia six years after the Chernobyl fallout. J Environ Radioact 31(3) 287-312. 

Levins, D. M., Ring, R. J. Hart, K. P. 1983. Mobilization of radionuclides and heavy metals in uranium mill and tailings dam circuits. Proc. Scientific Workshop on the Environmental Protection in the Alligator Rivers Region, sponsored by the Office of the Supervising Scientist, Jabiru, NT, Australia, 17-20 May, 10-1. 

Biological systems do not act simply as passive sinks for metals. They also modify their chemical environment and consequently the chemical speciation and mobility of nutrient and potentially toxic elements. Their influence on the mobility of radionuclides is less widely studied than that of other metals, but is certainly as important. The relevant factors include pH, redox potential, concentration of complexing ligands in solution, and mineral weathering. The relative importance depends on the soil and on the chemistry of the element considered, and no generalities can be made. It is not surprising that elements such as Se and Tc that exist in various oxidation states they sensitive to redox conditions. For other... 

Mobility of Radionuclides at a Uranium Mill Tailings Impoundment 151... 

The modem concept of RAW management suggests the immobilization of the wastes into solid matrices which possess chemical, mechanical, and radiation resistance. Thus, the goals of immobilization (as a rule, solidification) are to decrease the waste volume, to remove liquids, and to reduce the mobility of radionuclides after their disposal. According to the IAEA requirements (Technical Reports, 2003), the radionuclide-containing matrix should provide irreversible immobilization under the conditions of prolonged storage and disposal (Technical Reports, 2001). 

To ensure that the GDF is fit for purpose, we need to understand the long term effects of irradiation on materials as well as the interactions between the various components of a facility and the wastes. Radiochemical research will play an important role in helping us luiderstand these processes and will enable us to implement the best strategies for long term disposal. Studies on radionuclide release from spent fuel and vitrified wastes, the effects of complexants on radionuclide behaviour, the impact of microbes on the mobility of radionuclides and the behaviour of colloids (see Box 1) and non-aqueous phase liquids (see Box 2) - all of these pose questions that need to be answered as we develop the safety case for a geological disposal facility. 

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