Content and Behavior of Radiocesium in Undisturbed Bulgarian Soils

Results of the radiological monitoring of radiocesium content in soils from different regions of the country are presented and discussed in this work. Plain, hilly and mountain areas covering two thirds of the country are included in the study. The samples are analyzed by gamma-spectrometry. Some aspects of the fixation of Cesium in the soil are studied. Laboratory experiments were carried out trying to explain the quick distribution of Cs down the soil profile in 1986, immediately after the Chernobyl's contamination. It was established that the mobility of Cesium in soil is higher in the initial period after deposition and decreases with time.