Speciation of Artificial Radionuclides Co-60, Cs-137, Eu-152, and Am-241 in Bottom Sediments of the Yenisei River

The speciation of artificial radionuclides Co-60, Cs-137, Eu-152, and Am-241 in surface lavers of bottom sediments of the Yenisei river, collected within the near zone of impact of the Mining and Chemical Combine (Rosatom), was studied. In these samples the radionuclides Co-60, Eu-152, and Am-241 are mainly associated with fractions of humic and fulvic acids. The fraction of Eu-152 associated with nonsilicate iron is approximately 92%. The migration capability of radionuclides collected near the Atamanovo settlement decreases in the order Eu-152 > Am-241 > Co-60 > Cs-137. For samples collected near Bol'shoi Balchug settlement, this order is as follows: Eu-152 approximate to Am-241 > Co-60 Cs-137. The presence of radionuclide -hearing micro particles in bottom sediments considerably complicates the distribution of radionuclides, in particular, of Am-241 and C-137 s, among migration forms.