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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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Becker, G., Wade, S., Riggins, J. D., Cullen, T. B., Venn, C., & Hallen, C. P. (2005). Effect of Bast Mine treatment discharge on Big Mine Run AMD and Mahanoy Creek in the Western Middle Anthracite Field of Pennsylvania.
Abstract: The Bast Mine (reopened in 2001) and Big Mine are two anthracite coal mines near Ashland, PA, that were abandoned in the 1930's and that are now causing drastic and opposite effects on the water quality of the streams originating from them. To quantify these effects, multiple samples were taken at 5 different sites: 3 along Big Mine Run and 2 from Mahanoy Creek (1 upstream and 1 downstream of the confluence with Big Mine Run). At each site, one set of the samples was treated with nitric acid for metals survey, one set was acidified with sulfuric acid for nitrate preservation, one set was filtered for sulfate and phosphate tests, and one set was unaltered. Measurements of pH, TDS, dissolved oxygen, and temperature were made in the field. Alkalinity, acidity, hardness, nitrates, orthophosphates and sulfates were analyzed using Hach procedures. Selected metals (Fe, Ni, Mg, Ca, Cu, Zn, Hg, Pb) were analyzed utilizing flame atomic absorption spectroscopy. Drainage from the Bast Mine is actively treated with hydrated lime before the water is piped down to Big Mine Run. pH and alkalinity values were much higher at the outflow compared to those in the water with which it merged. The two waters could be visibly distinguished some distance downstream. pH values decreased, sulfate and dissolved iron increased and alkalinity was reduced to zero until the confluence with Mahanoy Creek. The high alkalinity, turbidity, TDS and calcium values in Mahanoy Creek were somewhat reduced downstream of the confluence with the much lower discharge Big Mine Run.
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Brown, M., Barley, B., & Wood, H. (2002). Minewater treatment; technology, application and policy. London: IWA Publishing.
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Banks, S. B., & Banks, D. (2001). Abandoned mines drainage; impact assessment and mitigation of discharges from coal mines in the UK. In R. N. Yong, & H. R. Thomas (Eds.), Geoenvironmental engineering Engineering Geology (pp. 31–37). 60.
Abstract: The UK has a legacy of pollution caused by discharges from abandoned coal mines, with the potential for further pollution by new discharges as groundwaters continue to rebound to their natural levels. In 1995, the Coal Authority initiated a scoping study of 30 gravity discharges from abandoned coal mines in England and Scotland. Mining information, geological information and water quality data were collated and interpreted in order to allow a preliminary assessment of the source and nature of each of the discharges. An assessment of the potential for remediation was made on the basis of the feasibility and relative costs of alternative remediation measures. Environmental impacts of the discharges and of the proposed remediation schemes were also assessed. The results, together with previous Coal Authority studies of discharges in Wales, were used by the Coal Authority, in collaboration with the former National Rivers Authority and the former Forth and Clyde River Purification Boards, to rank discharge sites in order of priority for remediation.
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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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