Peculiarities of distribution of anthropogenic radionuclides in soils and soil fractions of conjugated floodplain landscapes of the Yenisey River

¹ Vernadsky Institute of Geochemistry and Analytical Chemistry, Kosygin Street 19, 117975 Moscow, Russia
² Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry, Russian Academy of Sciences, Staromonetny Per., 35, Moscow 119017, Russia
³ Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Østeras, Norway

Abstract

The Yenisey River belongs to one of the main Siberian water systems flowing into the Arctic basin. Technogenic radionuclides have entered this system due to activities at the Krasnoyarsk Mining and Chemical Combine (KMCC), situated approximately 40 km downstream from the city of Krasnoyarsk (Zheleznogorsk), which began operations in August of 1958 (start-up of the first straight-through reactor, a second reactor was operated from 1961). In the period of 1958 to 1992 the river channel and flood plain were exposed to contamination at great distances downstream from the waste discharge point. Various long-lived radionuclides were measured in the environment such as ¹³⁷Cs, ⁶⁰Co, ¹⁵²Eu, ¹⁵⁴Eu with half-lives of 30.2, 5.3, 13.3 and 8.6 years correspondingly. Both reactors were decommissioned in 1992 and since then radionuclide discharges to the river have decreased by several tens of times.