Radioactivity Determination of Several Man-made Radionuclides in Soil Samples by γ Spectrometry

Surface and core soil samples collected from a radioactively contaminated region are analyzed by γ spectrometry. Soil is milled and sieved then contained with cylindrical plastic boxes (φ 75 mm×50 mm). 137Cs, 152Eu and 60Co are approximately homogeneous in samples of 40 mesh (0.42 mm), but 241Am may not uniform even in samples of 60 mesh ( 0.25 mm). Peaks count are up to 10% different between box is lying up and down on the top of detector. 241Am is mainly found in topsoils (0～5 cm), whereas 137Cs or 152Eu is to 30 cm in depth. The activity ratios of 152Eu to 154Eu are basically same (0.07) between different locations.