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Demchak, J., Morrow, T., Skousen, J., Donovan, J. J., & Rose, A. W. (2001). Treatment of acid mine drainage by four vertical flow wetlands in Pennsylvania Evolution and remediation of acid-sulfate groundwater systems at reclaimed mine-sites. Geochemistry – Exploration, Environment, Analysis, 1(1), 71–80.
Abstract: Acid mine drainage (AMD) is a serious problem in many watersheds where coal is mined. Passive treatments, such as wetlands and anoxic limestone drains (ALDs), have been developed, but these technologies show varying treatment efficiencies. A new passive treatment technique is a vertical flow wetland or successive alkalinity producing system (SAPS). Four SAPS in Pennsylvania were studied to determine changes in water chemistry from inflow to outflow. The Howe Bridge SAPS removed about 130 mg l (super -1) (40%) of the inflow acidity concentration and about 100 mg l (super -1) (60%) iron (Fe). The Filson 1 SAPS removed 68 mg l (super -1) (26%) acidity, 20 mg l (super -1) (83%) Fe and 6 mg l (super -1) (35%) aluminium (Al). The Sommerville SAPS removed 112 mg l (super -1) (31%) acidity, exported Fe, and removed 13 mg l (super -1) (30%) Al. The McKinley SAPS removed 54 mg l (super -1) (91%) acidity and 5 mg l (super -1) (90%) Fe. Acid removal rates at our four sites were 17 (HB), 52 (Filson1), 18 (Sommerville) and 11 (McKinley) g of acid per m (super 2) of surface wetland area per day (g/m (super 2) d (super -1) ). Calcium (Ca) concentrations in the SAPS effluents were increased between 8 and 57 mg l (super -1) at these sites. Equilibrators, which were inserted into compost layers to evaluate redox conditions at our sites, showed that reducing conditions were generally found at 60 cm compost depths and oxidized conditions were found at 30 cm compost depths. Deeply oxidized zones substantiated observations that channel flow was occurring through some parts of the compost. The Howe Bridge site has not declined in treatment efficiency over a six year treatment life. The SAPS construction costs were equal to about seven years of NaOH chemical treatment costs and 30 years of lime treatment costs. So, if the SAPS treatment longevity is seven years or greater and comparable effluent water quality was achieved, the SAPS construction was cost effective compared to NaOH chemical treatment. Construction recommendations for SAPS include a minimum of 50 cm of compost thickness, periodic replacement or addition of fresh compost material, and increasing the number of drainage pipes underlying the limestone.
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Skousen, J., Rose, A., Geidel, G., Foreman, J., Evans, R., & Hellier, W. (1998). A handbook of technologies for avoidance and remediation of acid mine drainage.
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Skousen, J. G., Rose, A., Geidel, G., Foreman, J., Evans, R., & Hellier, W. (1998). Handbook of Technologies for Avoidance and Remediation of Acid Mine Drainage. Morgantown: The National Mine Land Reclamation Center.
Abstract: An array of techniques have been developed during the last several decades to abate or control pollution by acid mine drainage (AMD) from coal and metal mines. Although most of these techniques are successful in eliminating or decreasing the deleterious effects of AMD in some situations, they are unsuccessful in others. Due to the inherent variability between mines and environmental conditions, no one abatement or treatment technique is effective on all sites, and selection of the best method on each site is difficult given the array of methods available. The techniques also vary in the type and size of problem they are capable of handling. Their individual costs, effectiveness, and maintenance are also important considerations. Therefore, accurate information is needed to understand the limitations of the various methods and their response to various site variables. Continued research is imperative for field testing of existing technologies, as well as continued development of new technologies. At present, there is no authoritative guide or manual to assist in evaluating the best technique for a given situation. In order to continue to mine coal and other minerals without harming the environment, the best science and techniques must be identified and implemented in order to minimize the production of AMD. To accomplish this goal, the Acid Mine Drainage Technology Initiative (ADTI) was organized to promote communication among scientists and engineers dealing with AMD, and to develop a consensus on the identification and optimum usage of each method. The intent is to provide information on selection of appropriate techniques for specific problems that will ultimately lead to a higher level of success in avoidance of AMD and remediation of existing sources, at a savings in cost and staff time, and with greater assurance that a planned technique will accomplish its objective. This effort will result in enhancement of mine drainage quality, improvement in stream cleanup and its cost effectiveness, and development of a mechanism for technology transfer.
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Ziemkiewicz, P. F., Skousen, J. G., & Simmons, J. (2003). Long-term Performance of Passive Acid Mine Drainage Treatment Systems. Mine Water Env., 22(3), 118–129.
Abstract: State and federal reclamation programs, mining operators, and citizen-based watershed organizations have constructed hundreds of passive systems in the eastern U.S. over the past 20 years to provide reliable, low cost, low maintenance mine water treatment in remote locations. While performance has been reported for individual systems, there has not been a comprehensive evaluation of the performance of each treatment type for a wide variety of conditions. We evaluated 83 systems: five types in eight states. Each system was monitored for influent and effluent flow, pH, net acidity, and metal concentrations. Performance was normalized among types by calculating acid load reductions and removals, and by converting construction cost, projected service life, and metric tonnes of acid load treated into cost per tonne of acid treated. Of the 83 systems, 82 reduced acid load. Average acid load reductions were 9.9 t/yr for open limestone channels (OLC), 10.1 t/yr for vertical flow wetlands (VFW), 11.9 t/yr for anaerobic wetlands (AnW), 16.6 t/yr for limestone leach beds (LSB), and 22.2 t/yr for anoxic limestone drains (ALD). Average costs for acid removal varied from $83/t/yr for ALDs to $527 for AnWs. Average acid removals were 25 g/m2/day for AnWs, 62 g/m2/day for VFWs, 22 g/day/t for OLCs, 28 g/day/t for LSBs, and 56 g/day/t for ALDs. It appears that the majority of passive systems are effective but there was wide variation within each system type, so improved reliability and efficiency are needed. This report is an initial step in determining passive treatment system performance; additional work is needed to refine system designs and monitoring.
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Skousen, J., & Jenkins, M. (2001). Acid mine drainage treatment costs with calcium oxide and the Aquafix machine. Green Lands, 31(3), 46–51.
Keywords: acid mine drainage; chemical composition; Clay County West Virginia; coal mines; cost; decontamination; ground water; instruments; lime; Mary Ruth Mines; mines; pollution; Preston County West Virginia; remediation; sludge; surface water; techniques; United States; water pollution; water treatment; West Virginia 22, Environmental geology
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