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Tarutis Jr, W. J., Stark, L. R., & Williams, F. M. (1999). Sizing and performance estimation of coal mine drainage wetlands. Ecological Engineering, 12(3-4), 353–372.
Abstract: The effectiveness of wetland treatment of acid mine drainage (AMD) was assessed using three measures of performance: treatment efficiency, area-adjusted removal, and first-order removal. Mathematical relationships between these measures were derived from simple kinetic equations. Area-adjusted removal is independent of pollutant concentration (zero-order reaction kinetics), while first-order removal is dependent on concentration. Treatment efficiency is linearly related to area-adjusted removal and exponentially related to first-order removal at constant hydraulic loading rates (flow/area). Examination of previously published data from 35 natural AMD wetlands revealed that statistically significant correlations exist between several of the performance measures for both iron and manganese removal, but these correlations are potentially spurious because these measures are derived from, and are mathematical rearrangements of, the same operating data. The use of treatment efficiency as a measure of performance between wetlands is not recommended because it is a relative measure that does not account for influent concentration differences. Area-adjusted removal accounts for mass loading effects, but it fails to separate the flow and concentration components, which is necessary if removal is first-order. Available empirical evidence suggests that AMD pollutant removal is better described by first-order kinetics. If removal is first-order, the use of area-adjusted rates for determining the wetland area required for treating relatively low pollutant concentrations will result in undersized wetlands. The effects of concentration and flow rate on wetland area predictions for constant influent loading rates also depend on the kinetics of pollutant removal. If removal is zero-order, the wetland area required to treat a discharge to meet some target effluent concentration is a decreasing linear function of influent concentration (and an inverse function of flow rate). However, if removal is first-order, the required wetland area is a non-linear function of the relative influent concentration. Further research is needed for developing accurate first-order rate constants as a function of influent water chemistry and ecosystem characteristics in order to successfully apply the first-order removal model to the design of more effective AMD wetland treatment systems.
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Wieder, R. K. (1989). A survey of constructed wetlands for acid coal mine drainage treatment in the Eastern United States. Wetlands, 9(2), 299–315.
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Wiseman, I. (2002). Constructed wetlands for minewater treatment. Bristol, England: Environment Agency.
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Wolkersdorfer, C., & Younger, P. L. (2002). Passive mine water treatment as an alternative to active systems. Grundwasser, 7(2), 67–77.
Abstract: For the treatment of contaminated mine waters reliable treatment methods with low investment and operational costs are essential. Therefore, passive treatment systems recently have been installed in Great Britain and in Germany (e.g. anoxic limestone drains, constructed wetlands, reactive barriers, roughing filters) and during the last eight years such systems successfully treated mine waters, using up to 6 ha of space. In some cases with highly contaminated mine water, a combination of active and passive systems should be applied, as in any case the water quality has to reach the limits. Because not all the processes of passive treatment systems are understood in detail, current research projects (e.g. EU-project PIRAMID) were established to clarify open questions.
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Younger, P. L., Banwart, S. A., & Hedin, R. S. (2002). (B. J. Alloway, & J. T. Trevors, Eds.). Mine water; hydrology, pollution, remediation. Dordrecht: Kluwer Academic Publishers.
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