Uranium Mobility in Waste Materials Generated by Uranium Mining and Hydrometallurgy: Implications for its In-Situ Immobilization

Abstract

Six uranium tailings samples from the shallow depth of two large-scale uranium tailings ponds in South China, which were affected by pedogenesis, were analyzed to determine the occurrence modes of uranium. The results demonstrated that an average of nearly 80% of the uranium in the samples was mobile and potentially mobile, indicating that this type of uranium tailings could significantly threaten their ambient environment when their contents of uranium were relatively high. In this sense, the possibility of the in-situ immobilization of active uranium in the uranium tailings was discussed. The experimental data indicated that the active uranium could be immobilized through its reaction with phosphate, which was theoretically feasible and promising in curbing uranium pollution.