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Simmons, J., Ziemkiewicz, P., & Black, D. C. (2002). Use of Steel Slag Leach Beds for the Treatment of Acid Mine Drainage. Mine Water Env., 21(2), 91–99.
Abstract: Steel slag from the Waylite steel-making plant in Bethlehem, Pennsylvania was leached with acidic mine drainage (AMD) of a known quality using an established laboratory procedure. Leaching continued for 60 cycles and leachates were collected after each cycle. Results indicated that the slag was very effective at neutralizing acidity. The AMD/slag leachates contained higher average concentrations of Ba, V, Mn, Cr, As, Ag, and Se and lower average concentrations of Sb, Fe, Zn, Be, Cd, Tl, Ni, Al, Cu, and Pb than the untreated AMD. Based on these tests, slag leach beds were constructed at the abandoned McCarty mine site in Preston County, West Virginia. The leach beds were constructed as slag check dams below limestone-lined settling basins. Acid water was captured in limestone channels and directed into basins to leach through the slag dams and discharge into a tributary of Beaver Creek. Since installation in October 2000, the system has been consistently producing net alkaline, pH 9 water. The treated water is still net alkaline and has a neutral pH after it encounters several other acidic seeps downstream.
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Demin, O. A., Dudeney, A. W. L., & Tarasova, I. I. (2002). Remediation of Ammonia-rich Minewater in Constructed Wetlands. Environ. Technol., 23(5), 497–514.
Abstract: A three-year study of ammonia removal from minewater was carried out employing constructed wetland systems (surface flow wetland and subsurface flow wetland cells) at the former Woolley Mine in West Yorkshire, UK The 1.4 Ha surface flow wetland (constructed in 1995) reduced the ammonia concentration from 3.5 – 4.5 mg l(-1) to < 2 3 mg V during the first half of the study and to essentially zero in the last year (2000 – 2001). About 25 % of contained ammonia was converted to nitrate, about 10 % was consumed by the plants and up to 30 % was converted to nitrogen gas. This maturation effect was attributed to increased depth of sludge from sedimentation of ochre, providing increased surface area for immobilisation of ammonia oxidising bacteria. The surface flow wetland finally removed 23 g m(-2) day(-1) ammonia in comparison with 3.8 g m(-2) day' for the subsurface flow (pea gravel) wetland cells, constructed for the present work and dosed with ammonium salts. Removal of ammonia by both systems was consistent with well-established mechanisms of nitrification and denitrification. It was also consistent with ammonia removal in wastewater wetland systems, although the greater aeration in the minewater systems obviated the need for special aeration cycles. The general role of wetland plants in such aerated conditions was attributed to maintaining hydraulic conditions (such as hydraulic efficiency and hydraulic resistance of substratum in subsurface flow systems) in the wetlands and providing a suspended solids filter for minewater.
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Matlock, M. M., Howerton, B. S., & Atwood, D. A. (2002). Chemical precipitation of heavy metals from acid mine drainage. Water Res, 36(19), 4757–4764.
Abstract: The 1,3-benzenediamidoethanethiol dianion (BDET, known commercially as MetX) has been developed to selectively and irreversibly bind soft heavy metals from aqueous solution. In the present study BDET was found to remove >90% of several toxic or problematic metals from AMD samples taken from an abandoned mine in Pikeville, Kentucky. The concentrations of metals such as iron, may be reduced at pH 4.5 from 194 ppm to below 0.009 ppm. The formation of stoichiomietric BDET-metal precipitates in this process was confirmed using X-ray powder diffraction (XRD), proton nuclear magnetic resonance (1H NMR), and infrared spectroscopy (IR).
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Scholz, M. (2002). Performance comparison of experimental constructed wetlands with different filter media and macrophytes treating industrial wastewater contaminated with lead and copper. Bioresource Technology, 83(2), 71–79.
Abstract: The aim of this study was to investigate the treatment efficiency of passive vertical-flow wetland filters containing different macrophytes (Phragmites and/or Typha) and granular media with different adsorption capacities. Gravel, sand, granular activated carbon, charcoal and Filtralite (light expanded clay) were used as filter media. Different concentrations of lead and copper sulfate were added to polluted urban stream inflow water to simulate pretreated mine wastewater. The relationships between growth media, microbial and plant communities as well as the reduction of predominantly lead, copper and five-day biochemical oxygen demand (BOD5) were investigated. An analysis of variance showed that concentration reductions (mg 1(-1)) of lead, copper and BOD5 were significantly similar for the six experimental wetlands. Microbial diversity was low due to metal pollution and similar for all filters. There appears to be no additional benefit in using adsorption media and macrophytes to enhance biomass performance during the first 10 months of operation. (C) 2002 Elsevier Science Ltd. All rights reserved.
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Kuyucak, N. (2002). Acid mine drainage prevention and control options. CIM Bull., 95(1060), 96–102.
Abstract: Acid mine drainage (AMD) is one of the most significant environmental challenges facing the mining industry worldwide. It occurs as a result of natural oxidation of sulphide minerals contained in mining wastes at operating and closed/decommissioned mine sites. AMD may adversely impact the surface water and groundwater quality and land use due to its typical low pH, high acidity and elevated concentrations of metals and sulphate content. Once it develops at a mine, its control can be difficult and expensive. If generation of AMD cannot be prevented, it must be collected and treated. Treatment of AMD usually costs more than control of AMD and may be required for many years after mining activities have ceased. Therefore, application of appropriate control methods to the site at the early stage of the mining would be beneficial. Although prevention of AMD is the most desirable option, a cost-effective prevention method is not yet available. The most effective method of control is to minimize penetration of air and water through the waste pile using a cover, either wet (water) or dry (soil), which is placed over the waste pile. Despite their high cost, these covers cannot always completely stop the oxidation process and generation of AMD. Application of more than one option might be required. Early diagnosis of the problem, identification of appropriate prevention/control measures and implementation of these methods to the site would reduce the potential risk of AMD generation. AMD prevention/control measures broadly include use of covers, control of the source, migration of AMD, and treatment. This paper provides an overview of AMD prevention and control options applicable for developing, operating and decommissioned mines.
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