Integration project of fundamental research of the UB RAS and the SB RAS "Comparative analysis of peculiarities of technogenic radionuclide migration in large water ecosystems of Siberia, Urals and Ukraine by the example of the Enisei river, Ob-Irtysh river system and water reservoirs of the Chernobyl estrangement zone”. Coordinators: UB RAS - А.V. Trapeznikov (Institute of Plant and Animal Ecology); SB RAS - А.G. Degermendzhi (Institute of Biophysics); Ukraine NAS - М.I. Kuzmenko (Institute of Hydrobiology). Project supervisor at the UB RAS –Е.V. Polyakov
Executing institutions: Institute of Biophysics SB RAS Sukachyov Institute of Forest SB RAS Institute of Inorganic Chemistry SB RAS Institute of Geology at the Trofimuk United Institute of Geology, Geophysics and Mineralogy SB RAS Institute of Plant and Animal Ecology UB RAS Institute of Solid State Chemistry UB RAS Institute of Hydrobiology, Ukraine NAS
Over the last 10 years, the scientists at the ISSCh UB RAS have formulated and developed a physicochemical approach to the solution of the problem of the state and forms of radionuclide and microelement migration in natural water systems under natural heterogeneity conditions. This approach is based on consecutive consideration of heterogenic equilibria and steady states of microelements when they interact with ion-molecular environment and existing and emerging impurity phases of chemical (and possibly biological) genesis. The study was based on the regularities of aquoacide theory, ion exchange thermodynamics, and physicochemistry of surface and colloid systems. It was shown that the natural mobility of microelements in an inorganic subsystem of natural water ecosystems can be rather accurately described in terms of the formulated concepts about the plurality of equilibrium or steady states of microelements in solutions and their heterogeneous interactions with the environment. In particular, using the elaborated models of microelement reactivity and experimental radiochemical and geochemical data, we were the first to propose and substantiate a consistent mechanism of strontium, plutonium and americium radionuclide migration in some technical water reservoirs of the Production Association Mayak. We have developed a new method of colloid chemical extraction for tracing the colloid state of microelements in aqueous solutions. The methods of colloid chemical extraction and mass-spectrometry with inductively coupled plasma were employed to obtain pioneering data on the ratio of ion-molecular and colloid components in fresh water samples, which were generalized in two monographs (Polyakov, 2000; Polyakov 2003).
Anticipatedresults: 1. Regular features of radionuclide migration in water and bottom sediment of various water reservoirs will be found out and radionuclide will be ranged according to their mobility under different conditions. 2. Coefficients of accumulation of technogenic radionuclides (including transuranium elements) by water organisms will be calculated and bioindicators will be found out. A database of the accumulating ability of water organisms in different water reservoirs with respect to technogenic radionuclides will be created. 3. The accumulation of technogenic radionuclides including transuranium elements by water organisms of different trophic levels will be estimated and the factor of the trophic chain length in the accumulation of radionuclides will be compared for different water reservoirs. 4. The accumulation of radionuclides in some regions of the Enisei river, Ob-Irtysh river system and Chernobyl zone water reservoirs will be estimated and compared. 5. We shall attempt to find out the contribution from (role of) the radionuclide source and the way of appearance (damage or constant discharge) to the specific character of radioactive pollution of the examined water reservoirs. 6. Based on the comparative content of tritium in the water reservoirs, we shall show up the radionuclide sources and estimate the scope of radionuclide transfer with stream of these rivers. 7. We shall find out stable parameters in the distribution of radionuclides and their ratios in bottom sediments and flood-land soils. Layers of bottom sediments and flood-land soils of the Enisei river, the Ob-Irtysh river system and the Chernobyl zone water reservoirs will be dated considering the ratio of isotopes of selected radionuclides. 8. A physicochemical model of heavy metal and radionuclide migration will be created using a selected water ecosystem as an example. 9. External and internal radiation doses of hydrobionts in different water reservoirs will be calculated. 10. Data on citogenetic and physiological parameters of the state of cells of water organisms having different radiation doses will be obtained. 12. Efficiency of methods for the rehabilitation of highly radioactive areas of the Ob-Irtysh river system and the Chernobyl zone water reservoirs used earlier will be compared.
