Radioactivity in sediments from the Grliska impoundment

The concentrations of the fission radionuclide 137Cs, an activation radionuclide 134Cs and the naturally occurring radionuclides 40K, 226Ra and 232Th were measured by gamma spectrometry in the sediment and water samples collected from the Grliska artificial lake and its tributaries. The deposition of radiocesium per square meter of sediments ranged from 2799 to 6158 Bq/m2. The total gamma activity of sediments appeared to be due to all determined radionuclides with a major contribution of the naturally occurring radiopotassium. Activity ratio recalculated to April 1986 showed that radiocesium in the Grliska impoundment environment originated from the Chernobyl fallout. Radionuclide partitioning coefficients were calculated in order to explain their transport/retardation in the Grliska impoundment ecosystem.