GEOTECHNICAL EVALUATION OF SOILS CONTAMINATED WITH TOXIC CHEMICALS

Soil contamination is one of the most widespread and serious environmental problems confronting the industrialized nations. Different contaminants have different chemical properties which influence the geochemical reactions induced in the soil as it gets contaminated. The main objective of this research was to assess the influence of contaminants on the geotechnical properties of soils.

Seven different types of commonly occurring organic contaminants were selected for this study – carbon tetrachloride, methylene chloride, tricholoroethylene, benzene, toluene, ethyl benzene and xylene. The effects of these contaminants on commonly occurring soil types were studied. A known quantity of the contaminant was added to each soil type, which was allowed to air dry in the laboratory for 1, 3, 7, and 15 days. Geotechnical properties, such as, specific gravity, hydraulic conductivity, Atterberg limits, grain size distribution, compaction characteristics, and the change in morphology of soil minerals were evaluated before and after the contamination for each time period. Statistical evaluation was conducted on the generated data to determine any possible correlation between physical properties of soil and contaminant and duration of exposure. Further work is in progress.