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Wolkersdorfer, C. (2005). Mine water tracer tests as a basis for remediation strategies. Chemie der Erde, 65(Suppl. 1), 65–74.
Abstract: Mining usually causes severe anthropogenic changes by which the ground- or surface water might be significantly polluted. One of the main problems in the mining industry are acid mine drainage, the drainage of heavy metals, and the prediction of mine water rebound after mine closure. Therefore, the knowledge about the hydraulic behaviour of the mine water within the flooded mine might significantly reduce the costs of mine closure and remediation. In the literature, the difficulties in evaluating the hydrodynamics of flooded mines are well described, but only few tracer tests in flooded mines have been published so far. Most tracer tests linked to mine water problems were related to either pollution of the aquifer or radioactive waste disposal and not the mine water itself. Applying the results of the test provides possibilities f or optimizing the outcome of the source-path-target methodology and therefore diminishes the costs of remediation strategies. Consequently, prior to planning of remediation strategies or numerical simulations, relatively cheap and reliable results for decision making can be obtained via a well conducted tracer test. < copyright > 2005 Elsevier GmbH. All rights reserved.
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Wiseman, I. M., Edwards, P. J., & Rutt, G. P. (2003). Recovery of an aquatic ecosystem following treatment of abandoned mine drainage with constructed wetlands. Land Contam. Reclam., 11(2), 221–230.
Abstract: Seven kilometres of the River Pelenna in South Wales were impacted for approximately 30 years by discharges from abandoned coal mines. Elevated iron and low pH caused significant ochreous staining and had detrimental effects on the river ecology. The River Pelenna Mine water project constructed a series of passive wetland treatment systems to treat these discharges. Monitoring of the performance and environmental benefits of these has been undertaken as part of an Environment Agency R&D project. This project has assessed the changes in water quality as well as monitoring populations of invertebrates, fish and birds between 1993 and 2001. Performance data from the wetlands show that on average the three systems are removing between 82 and 95% of the iron loading from the mine waters. In the rivers downstream, the dissolved iron concentration has dropped to below the Environmental Quality Standard (EQS) of 1 mg/L for the majority of the time. Increases in pH downstream of the discharges have also been demonstrated. Trout (Salmo trutta) recovered quickly following mine water treatment, returning the next year to areas that previously had no fish. Intermittent problems with overflows from the treatment systems temporarily depleted the numbers, but the latest data indicate a thriving population. The overflow problems and also background episodes of acidity have affected the recovery of the riverine invertebrates. However, there have been gradual improvements in the catchment, and in the summer of 2001 most sites held faunas which approached those found in unpolluted controls. Recovery of the invertebrate fauna is reflected in marked increases in the breeding success of riverine birds between 1996 and 2001. This study has shown that constructed wetlands can be an effective, low cost and sustainable solution to ecological damage caused by abandoned mine drainage.
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Wingenfelder, U., Hansen, C., Furrer, G., & Schulin, R. (2005). Removal of heavy metals from mine waters by natural zeolites. Environ Sci Technol, ES & T, 39(12), 4606–4613.
Keywords: Groundwater problems and environmental effects Pollution and waste management non radioactive remediation heavy metal mine drainage acid mine drainage; acidification; Central Europe; chemical composition; chemical fractionation; dissolved materials; Europe; framework silicates; geochemistry; grain size; heavy metals; hydrochemistry; ion exchange; lead; metals; mines; mining; mobilization; models; pH; pollutants; pollution; precipitation; remediation; samples; silicates; spectra; Switzerland; toxic materials; X-ray diffraction data; X-ray fluorescence spectra; zeolite group
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Wilmoth, R. C., Mason, D. G., & Gupta, M. (1972). Treatment of ferrous iron acid mine drainage by reverse osmosis.
Keywords: acid mine drainage; coal; controls; environmental geology; Environmental Protection Agency; experimental studies; ferrous iron; iron; metals; methods; mining; Mocanaqua; organic residues; Pennsylvania; pollution; reverse osmosis; sedimentary rocks; treatment; United States 22, Environmental geology
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Wilmoth, R. C. (1973). Environmental Protection Agency, Technology Series Report. Washington: U.S. Government Print. Offfice.
Abstract: EPA 670 2 73 100 Spiral-wound reverse osmosis systems were tested on four different acid mine drainage discharges in west virginia and pennsylvania. Comparison studies were made of the hollow-fiber, tubular, and spiral-wound systems at a ferrous iron acid discharge; and of hollow-fiber and spiral-wound systems at a ferric iron acid discharge. At all sites, the limiting factor in high recovery operation was calcium sulfate insolubility. An empirical formula was developed for predicting maximum recovery. Application of reverse osmosis was demonstrated to be technically feasible for a large percentage of acid mine drainage discharges. A process called 'neutrolisis' was developed in which the reverse osmosis brine is neutralized and clarified, and the supernatant recycled to the influent to the reverse osmosis unit. In this manner, the neutrolosis process discharges only a high quality product water and a neutralized sludge. Neutrolosis recoveries as high as 98.8 percent were achieved at a ferric iron acid discharge site. (epa)
Keywords: acid mine drainage
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