Laboratory study of landfill leachate effect on resistivity in unsaturated soil using cone penetrometer

Electrical resistivity of soils is dependent upon various factors, including soil type, water content, saturation and pore fluid property. Experimental works have been performed to investigate the relationship between electrical resistivity and unsaturated subsurface conditions with varying physical property and landfill leachate contamination. The moisture density can be the most effective indicator for describing the relationship between electrical resistivity and physical property of unsaturated subsurface. For three different tested soils, the electrical resistivity of soil exponentially decreased as moisture density increased. The adding of leachate having various ions decreased the electrical resistivity. Also, the formation factor can be described by the term of moisture density in unsaturated sand. The formation factor was higher when soil and pore water were contaminated by higher concentration of leachate than when soil and pore water are uncontaminated, since ionic movement is restrained by electro-chemical interactions between soil particles and leachate constituents.