Lead removal from groundwater by granular mixtures of pumice, perlite and lime using permeable reactive barriers

Permeable Reactive Barrier (PRB) is an in situ technology for remediation of contaminated groundwater. This article presents results of studies on three granular mixtures were used for remediation of lead (Pb2+) contaminated groundwater using PRBs. The mixtures were composed of pumice, perlite and lime in different proportions. Several column experiments were conducted for evaluation of performance of the mixtures for lead removal. The experiments were carried out for over 50 days to evaluate the long-term performance of the PRBs. It was found out that pumice-perlite mixture with a weight proportion of 1 : 1 and pumice-lime perlite mixture with a weight proportion of 2 : 2 : 1 can be used as effective reactive media for lead removal. The removal efficiency of the proposed mixtures was 99.9%. The permeability of the reactive media was relatively constant over 53 days continuous experiments and the results demonstrated that the mentioned mixtures have acceptable performance to maintain hydraulic conductivity of PRBs.