TRIGA Soil Decontamination by Electrokinetic Method

The experiment for removing cesium and cobalt from the contaminated soil around the TRIGA reactor in Korea using the electrokinetic method were conducted. To increase removal efficiency by the electrokinetic method, a device to restrain the pH increase in the soil column was suggested. An acetate buffer solution (CH₃COONa+CH₃COOH) was injected into the soil column and acetic acid periodically was injected into the cathode reservoir to restrain any pH increase. Many ¹³⁷Cs and ⁶⁰Co were transferred by electromigration rather than electroomosis during the intial remediation period, and no precipitate was formed in the soil column. 25% of cesium radioactivity in the soil column was removed after 10 days, while 94% of cobalt radioactivity was removed. Furthermore, the remaining radioactive concentrations predicted by the developed numerical model were similar to those obtained by experiment.