Microcosm Experiment for Evaluating Efficiency of Chemical Amendments on Remediation of Heavy Metal Contaminated Soil

Abstract

Heavy metal pollution in agricultural field near the abandoned metal mines is a critical problem in Korea. General remediation technique is to apply chemical amendments and soil covering. However, there is no specific guidelines for conducting soil covering. Therefore, main objective of this research was to determine optimum soil covering technique with microcosm experiment. Three different chemical amendments, lime stone (LS), steel slag (SS), and acid mine drainage sludge (AMDS), were examined and varied soil covering depth, 20, 30, 40cm, was applied to determine optimum remediation technique. Bioavailable heavy metal concentration in soil and total concentration of heavy metals in crop were monitored. Result showed that average heavy metal concentration in varied soil covering depth was ordered as 40 cm (14.5 mg kg -1 ) -1 ) -1 ) and also heavy metal concentration in crop was ordered as 40 cm (100 μg kg -1 ) -1 ) -1 ). In terms of chemical amendments, average heavy metal concentration was decreased as AMDS (150 μg kg -1 ) -1 ) -1 ). Overall, depth of soil covering should be over 30 cm to minimize bioaccumulation of heavy metals and SS and LS could be applied in heavy metal contaminated soil for remediation purposes.