Abstract
In order to select an available inlet source material for a migration test of radionuclides in a sedimentary layer, 8 different materials; carbonated cement, coastal sand, chromosorb, sandstone, cation-exchange resin, zeolite, silica gel and Toyoura standard sand, were tested in terms of adsorption ability and leaching rate with time for 60Co, 85Sr and 137Cs. The adsorption terms of adsorption ability and leaching rate with time for 60Co, 85Sr and 137Cs. The adsorption abilities obtained as distribution coefficients (Kds) were tested by batch-type experiments, and the leaching rates were examined using column-type experiments.
Among the materials, silica gel had the smallest Kd of approximately 60ml/g for the three radionuclides, and its Kd values did not fluctuate with time. Cement, sandstone and silica gel had a constant leaching rate for 60Co, 85Sr and 137Cs, ranging from 50 to 300ml inflow of groundwater. Approximately 70% of the three radionuclides were leached out from silica gel by 500ml inflow of groundwater. These results suggest that the silica gel is a suitable inlet source material for constantly supplying a solution with various radioactivities into a geologic layer.
