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Wolkersdorfer, C. (2002). Mine water tracing. Geological Society Special Publication, -(198), 47–60.
Abstract: This paper describes how tracer tests can be used in flooded underground mines to evaluate the hydrodynamic conditions or reliability of dams. Mine water tracer tests are conducted in order to evaluate the flow paths of seepage water, connections from the surface to the mine, and to support remediation plans for abandoned and flooded underground mines. There are only a few descriptions of successful tracer tests in the literature, and experience with mine water tracing is limited. Potential tracers are restricted due to the complicated chemical composition or low pH mine waters. A new injection and sampling method ('LydiA'-technique) overcomes some of the problems in mine water tracing. A successful tracer test from the Harz Mountains in Germany with Lycopodium clavatum, microspheres and sodium chloride is described, and the results of 29 mine water tracer tests indicate mean flow velocities of between 0.3 and 1.7 m min-1.
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Gusek, J. J. (2002). Proceedings, Annual Conference – National Association of Abandoned Mine Land Programs. Park City.
Abstract: There are basically two kinds of biological passive treatment cells for treating mine drainage. Aerobic Cells, containing cattails and other plants, are typically applicable to coal mine drainage where iron and manganese and mild acidity are problematic. Anaerobic Cells or Sulfate-Reducing Bioreactors are typically applicable to metal mine drainage with high acidity and a wide range of metals. Most passive treatment systems employ one or both of these cell types. The track record of aerobic cells in treating coal mine drainage is impressive, especially in the eastern coalfields. Sulfate-reducing bioreactors have tremendous potential at metal mines and coal mines, but have not seen as wide an application. This paper presents the advantages of sulfate-reducing bioreactors in treating mine drainage, including: the ability to work in cold, high altitude environments, handle high flow rates of mildly affected ARD in moderate acreage footprints, treat low pH acid drainage with a wide range of metals and anions including uranium, selenium, and sulfate, accept acid drainagecontaining dissolved aluminum without clogging with hydroxide sludge, have life-cycle costs on the order of $0.50 per thousand gallons, and be integrated into “semi-passive” systems that might be powered by liquid organic wastes. Sulfate reducing bioreactors might not be applicable in every abandoned mine situation. However a phased design program of laboratory, bench, and pilot scale testing has been shown to increase the likelihood of a successful design.
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Gobla, M. J. (2002). A rapid response to cleanup – Gilt Edge Superfund Site, South Dakota. Tailings and Mine Waste '02, , 421–425.
Abstract: The Gilt Edge gold mine is an acid drainage site that has been put on an accelerated closure schedule. The mine ceased activities in 1999 when Dakota Mining Corporation declared bankruptcy forcing the State of South Dakota to immediatly assume water treatment operations. Evaluation of conceptual closure plan options and cost estimates led the State of South Dakota to a decision to seek Federal assistance. The site has quickly moved into reclamation mode for the principal contamination source, the Ruby waste-rock dump. Designs and specifications for capping the Ruby waste-rock dump were prepared while Superfund listing was pursued. In October of 2000, mobilization of the first reclamation contractor began and by December the site was added to the National Priorities List. Capping the waste-rock dump will address a major acid drainage source. Water treatment requirements are expected to decline as conventional methods such as diverting clean water, backfilling, grading, capping, limestone neutralization, and revegetation are implemented. Acid seepage from underground workings, steep highwalls, and some pit backfills will remain. Major field trials of emerging technologies are nearing completion and some are showing promising results. Carbon reduction in a pit lake, and pyrite microencapsulation on simulated waste dumps, are showing initial success. Their application may minimize or eliminate the need for long-term active water treatment which has been a long sought goal for major acid rock drainage sites.
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Scholz, M. (2002). Mature experimental constructed wetlands treating urban water receiving high metal loads. Biotechnology Progress, 18(6), 1257–1264.
Abstract: The aim was to assess over 2 years the treatment efficiencies of vertical-flow wetland filters containing macrophytes and granular media of different. adsorption capacities. Different concentrations of lead and copper sulfate (constant for 1 year each) were added to urban beck inflow water in order to simulate pretreated (pH adjustment assumed) mine wastewater. After 1 year of operation, the inflow concentrations for lead and copper were increased from 1.30 to 2.98 and from 0.98 to 1.93 mg/L, respectively. However, the metal mass load rates (mg/m(2)/d) were increased by a factor of approximately 4.9 for lead and 4.3 for copper. No breakthrough of metals was recorded. Lead and copper accumulated in the biomass of the litter zone and rhizomes of the macrophytes. Furthermore, microbiological activity decreased during the second year of operation. Bioindicators such as ciliated protozoa and zooplankton decreased sharply in numbers but diatoms increased. In conclusion, the use of macrophytes and, adsorption media did not significantly enhance the filtration of lead and copper. Particulate lead is removed by filtration processes including straining. Furthermore, some expensive and time-consuming water quality variables can be predicted with less expensive ones such as temperature in order to reduce sampling costs.
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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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