Sorption of Uranium, Neptunium, and Plutonium onto Pyrite, Siderite, and Hematite after Their Microbial Transformation under the Conditions of Upper Aquifers

The influence of microorganisms collected from observation wells near the conserved liquid radioactive waste (RW) repository, B-2 reservoir, of the Siberian Chemical Combine on the immobilization of uranium, plutonium, and neptunium on pyrite, siderite, and goethite was studied. The results of laboratory experiments and thermodynamic simulation data show that the microbial transformation of iron-bearing minerals leads to an increase in the immobilization of actinides due to the appearance of new biogenic iron oxide/hydroxide/carbonate and iron sulfide mineral phases.