Managing Pore-Water Quality in Mine Tailings by Inducing Microbial Sulfate Reduction

A field-scale experiment was conducted to evaluate the potential for inducing microbial sulfate reduction as a passive in situ technique for managing water quality in mine tailings deposits. Sulfide- and carbonate-rich mine tailings, characterized by near-neutral pH pore water, were amended with 45% during the monitoring period, which coincided with the removal of Zn, Sb, and Tl. Mobilization of Fe and As occurred initially; however, subsequent decreases in aqueous concentrations were observed. Mineralogical investigation confirmed the presence of secondary FeS and ZnFeS phases. Amendment of tailings with a small and dispersed mass of organic carbon resulted in a general decrease in mass transport of sulfide oxidation products.