Influence of operation of thermal and fast reactors of the Beloyarsk NPP on the radioecological situation in river ecosystems.

The results of long-term radioecological monitoring of seven rivers in the 15-km zone of influence of the Beloyarsk Nuclear Power Plant have been presented. A comparative analysis of the content of a wide range of natural and artificial radionuclides in the main components of river ecosystems: surface waters, bottom sediments, floodplain soils, macrophytes and ichthyofauna has been made. The influence of waste technological waters of thermal (AMB-100 and AMB-200) and fast (BN-600 and BN-800) reactors of the Beloyarsk NPP on the content of radiologically significant isotopes in the water and bottom sediments of the Pyshma and Olkhovka rivers has been evaluated.

Po in Сrimean salt lakes.

This paper presents the results of radioecological monitoring study of natural radionuclide Po in 11 lakes located in different regions of the Crimean peninsula. These investigations of the Crimean salt lakes were conducted for the first time in the history. The main objectives of this work were: to determine the features of the Ро behavior in the salt lakes ecosystems, as well as calculation of the doses received by the lakes hydrobionts from α-radiation of absorbed Po.

The radiation exposure of fish in the period of the Techa river peak contamination.

Waterborne radioactive releases into the Techa River from the Mayak Production Association in Russia during 1949-1956 resulted in downstream contamination of the river ecosystem. The discharged liquid waste contained both short-lived isotopes (Zr, Nb, Ru, Ce, Y, Sr and Ba with half-life from 3 days to 1.02 years) and the long-lived Sr and Cs (half-life - 28.

[Modeling of Processes of Migration and Accumulation of Radionuclides in Freshwater Ecosystems by the Example of the Samson, Lev, Vandras Rivers Related to the Ob-Irtysh River Basin].

Mathematical models of horizontal distribution and migration of radionuclides are presented in water and floodplain soils of the Samson-Lev-Vandras river system related to the Ob-Irtysh river basin. Integral inventory of radionuclides in the main components of the river ecosystems is calculated. The estimated annual discharge of radionuclides from the Vandras river to the Great Salym river is given.

[Dynamics of Radioecological State of the Fresh-Water Ecosystems Affected by a Long-Term Impact from Nuclear Power Plant in the Frontiers of the Zone under Observation].

The results of radioecological studies of six small rivers situated in the surveillance zone of the Beloyarskaya NPP (BNPP) and around the cooling pond of the power plant are presented. 21 radionuclides and the total α- and β-activity were studied in the main components of the aquatic ecosystems. It is shown that after the 1st and 2nd BN PP blocks decommissioning the content of 60Co and 137Cs in the Beloyarskoye storage pond water, sediments, fish fauna and macrophytes dropped tens and hundreds of times.