Determination of diffusion coefficient of radioelements in the Rhone sediments

The transfer phenomena of 141Ce, 60Co, 137Cs, 54Mn, 85Sr and 65Zn in the Rhone sediments were studied in our laboratory. The transfer of the various radioelements in the environment concerned obeys Fick's second law of diffusion. The diffusion coefficients (D) of 85Sr and 54Mn were determined. They are respectively 2.1 × 10−2 cm2/day and 1.1 × 10−2 cm2/day. The values of the diffusion coefficients of the other elements were not determined accurately enough due to their fixation very near the sediment bed surface. However, they are expected to follow the same diffusion law according to the experimental protocol used. The stable elements in the Rhone sediments were analysed by various spectra-photometric methods and by neutron activation.