ИСТИНА

Quantitative characteristics of dissolved and particulate radiocaesium wash-off from contaminated watersheds after the FDNPP accident are calculated based on published monitoring data and results of field experiments on standard USLE runoff plots. Comparative analysis is provided for radiocaesium wash-off parameters and distribution coefficient in rivers and surface runoff on Fukushima and Chernobyl contaminated areas for the first years after the accidents. It is found that radiocaesium distribution coefficient in Fukushima rivers is essentially higher (1-2 orders of magnitude)than correspondent values for rivers and surface runoff of the Chernobyl zone. Normalized dissolved wash-off coefficients for Fukushima watersheds are 1-2 orders of magnitude lower correspondent values for Chernobyl zone. Normalized particulate wash-off coefficients are comparable for Fukushima and Chernobyl