Sorption of Cesium on Soil from Disposal Site Candidate at Lemahabang

Experiments of radionuclide interaction with soil taken from disposal site candidate have been done. Objective of the experiment is to study the capability of soil from Lemahabang area to absorb cesium radionuclide. Soil samples were taken out from radwaste disposal site candidate. Parameters to be studied were sorption kinetic, desorption, sorption isotherm and effect of ion Ca²⁺ to Cs-137 sorption on soil samples. The experiments were performed through batch method, where groundwater and surface water used as a solution. For sorption isotherm, concentration of CsCI ranged from 10^-8 to 10^-2 N, and concentration of CaCl₂.2H₂O as a Ca²⁺ ion simulation ranged from 10^-6 to 10^-2 M. Particle size of the sample was 100 mesh. The obtained result shown that sorption equilibrium reached after contact time 2-3 days, with Kd values relatively similar for groundwater and surface water. For it's desorption result shown an identically and also for sorption isotherm of soil samples obeyed Freundlich Law. Variation of ion Ca²⁺ on solution did not decrease of Cs-137 sorption capability of soil samples. The result showed that there are a good factor for retard the radionuclide transport from the facility to environment. (author)