Risk management for waste disposal sites and the leakage prevention of hazardous chemicals are quite important issues to improve the subsurface environment system including soil and groundwater. The existing techniques for monitoring and controlling chemicals in waste landfills are summarized to clarify the breakthrough for the future research and development. Considering the problems in waste sites and the urgent situation of leakage or spill of hazardous chemicals, we are developing the advanced barrier system for control of hazardous chemicals. The system consists of the active electrochemical barrier for detecting and cleaning contaminants, the soil metamorphic physical barrier, and the high precision technique for monitoring contaminant transport.
The developed techniques will be applied to subsurface environment for controlling hazardous chemicals and for repairing contaminated soils. In addition, the numerical model for predicting contaminant transport and assessing barrier techniques has been developed, using the original concept of multiphase fluids with physical and chemical interactions between solution and porous media.