Classification of Mine Drainages in Japan Based on Water Quality: Consideration for Constructed Wetland Treatments

As a passive technology, constructed wetlands (CWs) are promising candidates for mine-drainage treatment. However, the design and operation of CWs have not been fully established because chemical compositions mine drainage diverse. In this study data sets 100 drainages in Japan were classified using multivariate analysis based on water quality. Mine was into eight types ratio concentrations Cd, Pb, As, Cu, Zn, Fe, Mn to effluent standard: (I) neutral low metal concentration, (II) weakly acidic (III) high Zn (IV) concentrations, (V) (VI) Fe (VII) extremely (VIII) concentration. Mechanisms removing metals discussed classification. Metal hydroxides Cd can precipitate with an increasing pH. Under oxidative conditions, dissolved oxidized oxides. reductive Cu as sulfides. This classification will be helpful systematic CWs.