Spatial concentration distributions in soil of natural and manmade radionuclides

Numerous measurements have been conducted since the Chernobyl reactor accident in order to determine the depositions of artificial radionuclides, especially those of Cs-137 and Cs-134, in soil. As a consequence of the direction in which the radioactive plume moved in the first few days in May 1986, the cesium contamination in the Federal Republic of Germany is characterized by a general north-south gradient. Typical levels in the northern part are below 3 kBq/m2, while levels found in the southern part of the Federal Republic ranged as high as 100 kBq/m2 and even higher. The measured activity concentrations were used to calculate the local gamma dose rates 1 m above ground and compare them with the measurements. (orig.)