Study of Uranium Mobility in Model Soil Media in the Presence of Metallic Iron and Aluminum

The study of uranium mobility in soil media with different pH values at introduction of metal plates Al and Fe to create reducing conditions was carried out. The situation of solid radioactive waste (SRW) disposal at Rosatom facilities was modeled. The forms of uranium in soils were determined by the method of step leaching according to the Clement's scheme. It was revealed that the most effective were acidic media with the addition of peat, where >90 % of U remains in the residual "fixed" fraction binded with organic matter. It was noted that in neutral medium (chernozem) uranium mobility significantly depends on its amount in the system (1 and 5 % by mass), and in alkaline medium excess of carbonates increases uranium mobility due to the formation of uranyl-carbonate complexes in solution. It is confirmed that uranium accumulation is most intensive in acidic and neutral media.