AN ELECTROCHEMICAL TECHNIQUE FOR MINIMIZING SOIL AND GROUND WATER CONTAMINATION BY HEAVY METALS LEACHED FROM SOLID INDUSTRIAL WASTES

Abstract

Indiscriminate dumping of solid industrial wastes in un-engineered sites and the consequent soil and water contamination by heavy metals -- dissolved in rain water -- is a major environmental hazard in India. This study addresses an important issue: how do we minimize the rain water assisted transport of toxic heavy metals from solid wastes to the ground water? Preliminary experiments have shown that electrochemical fencing, which uses an electric field to capture the heavy metal ions, may be a viable technique for slowing down the rain-assisted transport of heavy metals through soil. Experiments simulating the natural rain fall conditions on a saturated soil covered with a dichromate residue have been carried out. The effect of applied voltage on the efficacy of electrochemical fencing has been investigated. A mathematical model that calculates the trajectory of Cr(VI) ions to predict the efficacy of electrochemical fencing has been formulated.