TITLE:
Natural and Artificial Radionuclides in River Bottom Sediments and Suspended Matter in the Czech Republic in the Period 2000-2010
AUTHORS:
Eduard Hanslík, Diana Marešová, Eva Juranová
KEYWORDS:
River Bottom Sediments; Suspended Matter; Surface Water; Uranium Industry; Radioactive Contamination; Radium-226; Radium-228; Potassium-40; Caesium-137
JOURNAL NAME:
Journal of Environmental Protection,
Vol.5 No.2,
February
26,
2014
ABSTRACT:
The concentrations of
natural radionuclides, radium-226, radium-228, and potassium-40, and the
artificial radionuclide caesium-137, in river bottom sediments and suspended
matter were monitored in the Czech Republic by the Czech Hydrometeorological
Institute during the period 2000-2010 and 2001-2010
respectively. The data were used to evaluate the natural background levels of
these radionuclides and the impact of human activities on the water
environment. For potassium-40 in sediments, the natural background level was
estimated to be 570 Bq/kg. To evaluate the background level for radium-226, the
river sites affected by human activities (mining and processing uranium ore,
coal) were eliminated from the assessment. The average natural background
values were 47.8 Bq/kg for radium-226 and 47.2 Bq/kg for radium-228 in
sediments and 86.5 Bq/kg for radium-226 and 87.9 Bq/kg for radium-228 in
suspended matter. The river sediments were identified as good indicators of radioactive
contamination, especially radium-226, which recorded historic contamination due
to former uranium mining and milling. The radium-226 contamination rate was
assessed using the ratio of radium-226 to radium-228. This ratio was used to
classify sediment according to the relative contamination from the uranium industry.
The residual contamination of caesium-137 due to the Chernobyl accident in 1986
was also assessed. Average values of caesium-137 were 14.0 Bq/kg in sediments and 25.0 Bq/kg in suspended matter.