Аннотация:Permeable reactive barriers (PRB) enable physical, chemical or biological in situ treatment of
contaminated groundwater by bringing it into contact with reactive materials. The reactive material is
inserted underground in a natural aquifer and intercepts the pollution plume as it is carried along
within the aquifer, and thus the contaminants are treated without either wholesale soil excavation or
water pumping. This cost-effective clean-up technology has much less impact on the environment than
other methods and is generally more economical over the long term as compared to other methods.
In this study sorption characteristics of different materials that can be used for creation of complex
multi-layer PRB were specified. For apatite, vermiculite, lightweight expanded clay aggregate (LECA),
wood sawdust, perlite, natural zeolite (TREYD) and shungite sorption coefficients (Kd) for 137Cs, 90Sr,
238U, 239Pu, 241Am, 99Tc and stable Cr(VI) were obtained. Speciations of these radionuclides on
materials were investigated using the method of sequential extraction.
Since one component of complex multi-layer PRB is denitrifying bacteria immobilized on the
carrier, microbiological influence on barrier materials should be estimated. Variation of Kd and
changes in speciation of sorbed radionuclides after microbiological treatment were analyzed.