ABSTRACT
The ability of passive bioreactor systems (anaerobic wetlands, passive bioreactors and permeable reactive barriers) to remove metals from mine drainage has been demonstrated. However, problems arise with the performance of some passive bioreactor systems. The overall goal of this project is to improve process performance of these systems. This will be done by first evaluating the effect of organic matter characteristics on the types, rate of growth and sustainability of microbial populations. Also, studies will be conducted on the effect of organic matter on metal speciation, complexation, and removal. The project tasks are: 1. Solid phase organic and inorganic material characterization (physical, chemical and microbial), 2. Batch studies on the effect of different PBR mixtures, 3. Bench-scale studies on the effect of selected substrate mixtures, 4. Field sampling of anaerobic wetland and passive bioreactor systems, and 5. Fate and transport modeling. This project will result in improved designs of passive bioreactor systems to achieve target metal concentrations and to protect aquatic and human health.
