Study on the horizontal transport of some radionuclides in the Wieprz river valley

A horizontal transport of radionuclides was studied by the analysis of the radioactivity of the surface soil samples from valleys of Wieprz river and its bottom sediments. Natural gamma-isotopes (K-40, U-238 and Th-232 series ) antropogenic (Cs-134 and (CS)-C-137) and alpha-isotopes Pu-238 and (PU)-P -239,240 were measured. The different kind of bed rock and terrain configur ation, influenced the radionuclide transportation from the soil to river bo ttom sediments. Radioactivity of the sediment samples is definitely lower t han the soils. Very strong adsorption of isotopes in soil hinders their hor izontal migration. Calculated (238)pu/(239,240)pu ratio is characteristic f or global fallout and about 90% of the Cs-137 comes from Chernobyl.