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Kepler, D. A., & Mc Cleary, E. C. (1994). Successive Alkalinity-Producing Systems (SAPS) for the Treatment of Acid Mine Drainage. Proceedings, International Land Reclamation and Mine Drainage Conference, 1, 195–204.
Abstract: Constructed wetland treatment system effectiveness has been limited by the alkalinity-producing, or acidity-neutralizing, capabilities of systems. Anoxic limestone drains (ALD's) have allowed for the treatment of approximately 300 mg/L net acidic mine drainage, but current design guidance precludes using successive ALD's to generate alkalinity in excess of 300 mg/L because of concerns with dissolved oxygen. “Compost” wetlands designed to promote bacterially mediated sulfate reduction are suggested as a means of generating alkalinity required in excess of that produced by ALD's. Compost wetlands create two basic needs of sulfate reducing bacteria; anoxic conditions resulting from the inherent oxygen demand of the organic substrate, and quasi-circumneutral pH values resulting from the dissolution of the carbonate fraction of the compost. However, sulfate reduction treatment area needs are generally in excess of area availability and/or cost effectiveness. Second generation alkalinity-producing systems demonstrate that a combination of existing treatment mechanisms has the potential to overcome current design concerns and effectively treat acidic waters ad infinitum. Successive alkalinity-producing systems (SAPS) combine ALD technology with sulfate reduction mechanisms. SAPS promote vertical flow through rich organic wetland substrates into limestone beds beneath the organic compost, discharging the pore waters. SAPS allow for conservative wetland treatment sizing calculations to be made as a rate function based on pH and alkalinity values and associated contaminant loadings. SAPS potentially decrease treatment area requirements and have the further potential to generate alkalinity in excess of acidity regardless od acidity concentrations.
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Cravotta, C. A., III, Watzlaf, G. R., Naftz, D. L., Morrison, S. J., Fuller, C. C., & Davis, J. A. (2002). Design and performance of limestone drains to increase pH and remove metals from acidic mine drainage Handbook of groundwater remediation using permeable reactive barriers; applications to radionuclides, trace metals, and nutrients.. Amsterdam: Academic Press.
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Ziemkiewicz, P. F., Meek, F. A., Jr., Skousen, J. G., & Ziemkiewicz, P. F. (1996). Long term behavior of acid forming rock; results of 11-year field studies. In Acid mine drainage control and treatment. Morgantown: West Virginia University and the National Mine Land Reclamation Center.
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Simmons, J. A., Andrew, T., Arnold, A., Bee, N., Bennett, J., Grundman, M., et al. (2006). Small-Scale Chemical Changes Caused by In-stream Limestone Sand Additions to Streams. Mine Water Env., 25(4), 241–245.
Abstract: In-stream limestone sand addition (ILSA) has been employed as the final treatment for acid mine drainage discharges at Swamp Run in central West Virginia for six years. To determine the small-scale longitudinal variation in stream water and sediment chemistry and stream biota, we sampled one to three locations upstream of the ILSA site and six locations downstream. Addition of limestone sand significantly increased calcium and aluminum concentrations in sediment and increased the pH, calcium, and total suspended solids of the stream water. Increases in alkalinity were not significant. The number of benthic macroinvertebrate taxa was significantly reduced but there was no effect on periphyton biomass. Dissolved aluminum concentration in stream water was reduced, apparently by precipitation into the stream sediment.
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Hayward, D., & Barnard, R. (1993). Treatment of acid mine wastewaters. Behandlung saurer Grubenwässer. World Mining Equipment, 17(6), 36–37.
Abstract: Überblick über einschlägige Verfahren zum Ausfällen der sauren Betandteile, Entfernen der Schwermetalle, und Einstellen des pH-Wertes auf einen Wert von 6 bis 9. Hauptsächliche Verfahren zum Ausfällen sind: Ausfällen mit Kalkhydrat (Ca(OH)2), mit Kalkstein, Calcium- oder Natriumsulfid. Durch Abtrennen des Niederschlages in einem Kläreindicker und zusätzliche Reinigung durch Filtrieren kann ein Anteil von 90% der unlöslichen Schwermetallverbindungen entfernt werden. Allgemein wird mit diesem Verfahren ein Standardgehalt von 5 mg/l erreicht. Durch zusätzliche Anwendung physikochemischer Verfahren kann der Schwermetallgehalt weiter gesenkt werden: Mikrofiltration, Umkehrosmose, Elektrodialyse, Ionenaustausch, biochemische und spezielle chemische Verfahren können je nach Eigenart der Grubenwässer verwendet werden.
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