Assessment of Concentration of Radionuclides in River Water and Bottom Sediments

A. L. Krylov, A. V. Nosov, A. I. Kryshev, I. I. Kryshev, and V. P. Kiseliev

The results of modeling of 89, 90Sr, 137Cs, and 239, 240Pu migration in the Techa River are compared with observed data. It is shown that taking into account of the process of mass exchange between the main stream of a river and underflow is important for adequate modeling of migration and accumulation of radiative substances in a river. It is difficult to obtain results of modeling corresponding to the observed data if the process is neglected. Taking into account the mass exchange is especially important in developing models for long enough rivers that were polluted by radionuclides during long time. Authors believe that, in future, the considered aspects of modeling radioactive substances in rivers can be generalized on chemical polluting substances with similar physical and chemical properties, for example, heavy metals, phenols, etc.