One-dimensional column and three-dimensional box flushing of silicone emulsion-enhanced remediation for chlorinated solvent contaminated soils

Abstract

Aquifer contamination by dense non-aqueous phase liquids such as chlorinated solvents poses a huge threat to human health. Most chlorinated solvents biodegrade slowly under aerobic and anaerobic conditions. Furthermore, chlorinated solvents exist as free phase in aquifers and continuously contaminate groundwater because they have high density and low aqueous solubility. In this study, the feasibility of emulsion-based remediation for field application was investigated using a one-dimensional column and three-dimensional flushing. One-dimensional column experiments were performed to confirm the effects of soil components such as organics, silt, and clay on flushing performance. High organics (12%) and silt/clay (45%) inhibited solubilization of TCE. In three-dimensional flushing of TCE, a diagonal flow of emulsion was observed and downward migration of chlorinated solvents was prevented.