Fawcett, M. N. R. (1995). Management of AMD at Pine Creek Mine. Die Beherrschung des AMD-Problems in der Pine-Creek-Mine. In Second Australian Acid Mine Drainage Workshop, Charters Towers, AU, 28 31 March 1995 (pp. 83–90).
Abstract: In der Regenzeit 1991/1992 wurden überraschend im Bereich des australischen Goldbergwerks Pine Creek saure Grubenwässer festgestellt, die eine ernsthafte Umweltgefährdung und einen deutlichen Anstieg bei den Betriebskosten verursachten. Diese sauren Grubenwässer traten als Folge von Laugungserscheinungen in den Halden auf. Zur Verminderung der Reaktionsfähigkeit der sulfidischen Berge wurde beschlossen, die Halden mit mehreren Schichten inerten Materials geringer Permeabilität abzudecken. Diese Abdeckung wurde anschließend verdichtet und begrünt. Bei den späteren Abbauarbeiten wurde eine prophylaktische Minimierung der begünstigenden Reaktionsbedingungen vorgenommen. Es wurde eine Integration von Abbau und Sanierungsmaßnahmen realisiert, bei der offene Tagebauflächen mit Haldenbergen verfüllt wurden. Die haldengefüllten Tagebaurestlöcher wurden außerdem teilgeflutet, um den Sauerstoffzutritt zu minimieren. Aus den gewonnenen Erfahrungen wird die Schlußfolgerung gezogen, das AMD-Problem bereits in der Planungsphase zu berücksichtigen und umfassende Untersuchungen einzuleiten. Es sind nicht erst im Stadium der Sanierung, sondern bereits bei den Abbauaktivitäten geeignete Maßnahmen einzuleiten, um unangenehme Überraschungen durch saure Grubenwässer, die übrigens sehr teuer werden können, zu vermeiden.
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Eger, P., Melchert, G., & Wagner, J. (2000). Using passive treatment systems for mine closure – A good approach or a risky alternative? Min. Eng., 52(9), 78–83.
Abstract: In 1991, LTV Steel Mining decided to close an open-pit taconite mine in northeastern Minnesota using a passive-treatment approach consisting of limiting infiltration into the stockpiles and wetland treatment to remove metals. More than 50 Mt (55 million st) of sulfide-containing waste had been stockpiled adjacent to the mine during its 30 years of operation. Drainage from the stockpiles contained elevated levels of copper, nickel, cobalt and zinc. Nickel is the major trace metal in the drainages. Before the closure, the annual median concentrations ranged from 1.5 to 50 mg/L. Copper, cobalt and zinc are also present but they are generally less than 5% of the nickel values. Median pH levels range from 5 to 7.5, but most of the stockpile drainages have pH levels greater than 6.5. Based on the chemical composition of each stockpile, a cover material was selected. The higher the potential that a stockpile had to produce acid drainage, the lower the permeability of the capping material required. Covers ranged from overburden soil removed at the mine to a flexible plastic liner. Predictions of the reduction in infiltration ranged from 40% for the native soil to more than 90% for the plastic liner. Five constructed wetlands have been installed since 1992. They have removed 60% to 90% of the nickel in the drainages. Total capital costs for all the infiltration reduction and wetlands exceeded $6.5 million, but maintenance costs are less than 1% of those for an active treatment plant. Because mine-drainage problems can continue for more than 100 years, the lower annual operating costs should pay for the construction of the wetland-treatment systems within seven years.
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Eger, P., Melchert, G., Antonson, D., & Wagner, J. (1993). Magnesium hydroxide as a treatment for acid mine drainage in northern Minnesota. In B. A. Zamora, & R. E. Connolly (Eds.), Proceedings of the Annual National Meeting – American Society for Surface Mining and Reclamation, vol.10 (pp. 204–217). The challenge of integrating diverse perspectives in reclamation.
Abstract: Three alkaline materials were investigated for their suitability to treat acid mine drainage generated by a research facility located at a remote site in northern Minnesota. The materials investigated were hydrated lime, sodium hydroxide, and magnesium hydroxide. All three reagents were successful at raising pH and removing trace metals from the drainage, but the magnesium hydroxide had the added benefit of producing a maximum pH of approximately 9.5, while the other two reagents resulted in pH values of 12 and greater. In addition, the magnesium hydroxide was available as a high solid content slurry (58%) which simplified application and handling, and which produced the lowest volume of sludge of the materials tested.
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Diz, H. R. (1997). Chemical and biological treatment of acid mine drainage for the removal of heavy metals and acidity. Ph.D. thesis, Virginia Polytechnic Institute and State University,, Blacksburg.
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Dempsey, B. A., & Jeon, B. - H. (2001). Characteristics of sludge produced from passive treatment of mine drainage. Geochem.-Explor. Environ. Anal., 1(1), 89–94.
Abstract: In the 1994 paper by Brown, Skousen & Renton it was argued that settleability and wet-packing density were the most important physical characteristics of sludge from treatment of mine drainage. These characteristics plus zeta-potential, intrinsic viscosity, specific resistance to filtration, and coefficient of compressibility were determined for several sludge samples from passive treatment sites and for several sludge samples that were prepared in the laboratory. Sludge from passive systems had high packing density, low intrinsic viscosity, low specific resistance to filtration and low coefficient of compressibility compared to sludge that was produced after addition of NaOH.
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