Study on Radioactive Contaminated Soil Remediation Technologies and Selection Principles

Abstract

A large number of radioactive materials entered the soil environment by Fukushima nuclear accident, and large area of contaminated soil with radioactive materials became the thorniest problem of Japanese government after the accident. On the basis of the mechanism of radionuclide migration in the soil, such as physical migration, chemical migration, biological migration, and the composite of different migration processes, the series of radionuclide-contaminated soil repair methods is discussed. There are move and replace with out-soil methods aiming at physical migration, there are ion exchange method and oxidation-reduction method aiming at chemical migration, there are microbial remediation and phytoremediation aiming at biological migration. The advantages and disadvantages of different methods and applicable range are illustrated. The final remediation target is the first priority when selecting remediation methods. Then, the influence factors on remediation effect should be considered, including the principles of radiation protection, radioactive pollution levels, soil characteristics, hydrological and meteorological conditions, the radionuclide migration way influence. Finally, there will be a comprehensive comparison from method feasibility, economic affordability, and environmental and legal compatibility. The feasibility of remediation methods includes appropriate repair methods, acceptable repair time, good repair effect, etc. Economic affordability means repair costs can be bearable and as less as better. Environmental and legal compatibility refers that after the restoration the residual risk of nuclides in environment is acceptable and the long-term effect is negligible and meets the requirements of relevant laws and regulations standard.