Sorption of 137Cs, 90Sr, Se, 99Tc, 152(154)Eu, 239(240)Pu on fractured rocks of the Yeniseysky site (Nizhne-Kansky massif, Krasnoyarsk region, Russia)

The study demonstrates the effect of sorption properties of fractured host rocks from the Yeniseysky site (Nizhne-Kansky rock massif, Krasnoyarsk region) on the migration of dissolved radioactive components (137Cs, 90Sr, 79Se, 99Tc, 152(154)Eu, 239(240)Pu) in the deep geological conditions of a high-level radioactive waste repository. Estimates of radionuclide distribution coefficients between the aqueous solution and fractured rocks obtained from sorption experiments were used to study the influence of various petrographic types and fracture-filling substances on the retardation of radioactive components by different fractured rock units of Nizhne-Kansky rock massif. Based on the results of sorption experiments, we concluded that the type and attributes of rock discontinuities, as well as the mineral composition of the material in fractures, are crucial for the immobilization of radionuclides during their migration through a geological environment.