Stabilization of leachate contaminated soils using industrial by-products

Abstract

This paper reports the results from an experimental program to examine the effects of adding fly ash and rice husk ash on select geotechnical characteristics of industrial leachate contaminated plastic soils obtained from multiple sites of two different cities in Pakistan. The analysis revealed that the addition of fly ash and rice husk ash in a textile leachate contaminated soil could significantly reduce the plasticity and compression indices while improving both undrained shear strength and compaction characteristics. Similarly, adding fly ash in a paper leachate contaminated soil resulted in marked decrease in compression and plasticity indices, accompanied with a significant increase in undrained shear strength. Based on comprehensive chemical analysis and the results of scanning electron microscopy imaging, the stabilization mechanism of contaminated soils has been presented that would enhance our understanding of this complex process. Furthermore, the practical implication of this study has been demonstrated with the help of a simple case study, whereby a leachate contaminated soil taken from a different site has been treated and results have been presented to demonstrate immediate practical significance of this work.