P-4a-244 1 Various In-situ Methods in Study of the Chernobyl Deposit and Natural Radioactivity of the Soil

The contamination of soil after the Chernobyl accident was measured in Slovenia by different methods. Laboratory Ge-spectrometry was soon partially replaced by field GeHP-spectrometry. More detailed profile studies remained limited to the locations around Ljubljana and the nuclear installations. After the decay of other elements the contamination of 137Cs/134Cs could be studied by a portable NaI(Tl)-spectrometer. The depth profile was estimated from the amount of the scattered gamma-rays. Several improved methods of indirect or direct in-situ depth profile determination will be considered. 1