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Davison, W. (1988). Neutralizing Strategies For Acid Waters – Sodium And Calcium Products Generate Different Acid Neutralizing Capacities. Water Res, 22(5), 577–583.
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Sato, D., & Tazaki, K. (2000). Calcification treatment of mine drainage and depositional formula of heavy metals. Chikyu Kagaku = Earth Science, 54(5), 328–336.
Abstract: Depositional formula of heavy metals after disposal of the mine drainage from the Ogoya Mine in Ishikawa Prefecture, Japan, was mineralogically investigated. Strong acidic wastewater (pH 3.5) from pithead of the mine contains high concentration of heavy metals. In this mine, neutralizing coagulation treatment is going on by slaked lime (calcium hydroxides: Ca(OH) (sub 2) ). Core samples were collected at disposal pond to which the treated wastewater flows. The core samples were divided into 44 layers based on the color variation. The mineralogical and chemical compositions of each layer were analyzed by an X-ray powder diffractometer (XRD), an energy dispersive X-ray fluorescence analyzer (ED-XRF) and a NCS elemental analyzer. The upper parts are rich in brown colored layers, whereas discolored are the deeper parts. The color variation is relevant to Fe concentration. Brown colored core sections are composed of abundant hydrous ferric oxides with heavy metals, such as Cu, Zn, and Cd. On the other hand, S concentration gradually increases with depth. XRD data indicated that calcite decreases with increasing depth, and ettringite is produced at the deeper parts. Cd concentration shows similar vertical profile to those of calcite and ettringite. The results revealed that hydrous ferric oxides, calcite and ettringite are formed on deposition, whereby incorporating the heavy metals.
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Oster, A. (2005). Relocating the Inde river – Post-mining design of a river meadow landscape. Verlegung des Flusses Inde – Bergbauliche Gestaltung einer Flussauenlandschaft. World of Mining Surface & Underground, 57(5), 346–351.
Abstract: Vor dem Hintergrund einer planmäßigen Tagebauentwicklung muss der das Gewinnungsfeld in Nord-Süd-Richtung durchquerende Fluss Inde Ende 2005 bergbaulich in Anspruch genommen werden. Als Ersatz wurde auf Grundlage des Planfeststellungsbeschlusses vom 10.09.1998 eine neue Inde auf einer Länge von rd. 12 km erstellt. Rund 10 km der neuen Inde liegt innerhalb des Tagebaufeldes. Hierzu musste eine Flusslandschaft angelegt werden. Im Gegensatz bisher anthropogen geprägten Inde, ist eine naturnahe und weiträumige Flusslandschaft vorgesehen. Die Gestaltung soll, in Verbindung mit den zahlreichen eingebrachten Landschaftselementen wie Flutmulden, Altarmansätzen und Kolke, eine artenreiche und ökologisch hochwertige Auenlandschaft ermöglichen. Die Flutung der neuen Inde erfolgt auf Grundlage eines dreiphasigen Gewässerumschlusskonzeptes. Im Anschluss an die Flutung soll ein Monitoring- Programm zur Dokumentation der hydrodynamischen, morphologischen und landschaftsökologischen Entwicklung der Indeflur durchgeführt werden. Against the background of the scheduled eastward development of the Inden opencast mine, the Inde river which runs there must make way for mining operations at the end of 2005. Prior to this, as a replacement for the riverbed, which is some 4.5 km long, a riverscape has had to be created as a bypass in the west, mainly within the scope of rehabilitation measures. The model built for this purpose based on historical records provides for a close-to-nature and spacious riverscape with hand- and soft-wood meadows, unlike the anthropogenically marked Inde of today, with a meandering mean water bed. This design, in conjunction with the many installed landscape elements, like flood hollows, creeks and potholes, aims at creating a diverse and ecologically high-quality meadow landscape. The main factors impacting the river's route were the opencast mine's geometry and progress, as well as the planned and existing utilization of the land surfaces outside the opencast field. Besides these constraints, there were stipulated vertical points due to hydraulic requirements. The Inde plains, taking account of the planned route, were created on the basis of a design template, which provides for a stable level, a sealing layer and a cultivatable meadow substrate layer. In addition, the meadow substrate layer protects the sealing layer from erosion thanks to its medium- and coarse-grained gravel content. The Inde was constructed in the opencast field within the scope of rehabilitation in spreader operations, meaning that it was possible to dump the material to be installed in line with the design template and given elevations. The flooding of the 'new' Inde was based on a three-phase waterway rerouting concept and provided for increasing discharge quantities. This enabled a bottom covering layer to be formed successively, and ailowed the aquatic fauna to gently adapt to the changed living conditions and further seed material to be flushed in.
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Okuda, T., Ema, S., Ishizaki, C., & Fujimoto, J. (1991). Mine drainage treatment and ferrite sludge application. NEC Technical Journal, 44(5), 4–16.
Abstract: The `ferrite process' is an excellent method for treating waste water containing iron and arsenic, but cannot be directly applied to mine drainage where silicon and aluminum ions are present, because they strongly inhibit ferrite formation. As a result of the development of related technologies such as the elimination of silicon, the concentration of iron, and the oxidation of ferrous ions using iron-oxidation bacteria, a new ferrite formation process has been developed and applied to the mine drainage of the Matsuo Mine. The paper discusses the application of the ferrite sludge to magnetic marking materials, magnetic fluid for metal separation and recovery, and the semiactive magnetic damper is described. The related technologies which will be expected to play an important role in solving the environmental problems are also described. These technologies will change the ferrite sludge to beneficial materials, which can be used for carbon dioxide decomposing catalysts, reuse of dry batteries, fish gathering blocks, and cement tracer for ground improvement
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Morfitt, B., Brewer, W., & Frobel, R. (1998). Cleaning up the Summitville Mine Superfund Site. Geotechnical Fabrics Report, 16(5), 38–41.
Abstract: A multi-layered geosynthetic system that includes geosynthetic-clay liners (GCL) and a geonet-composite drain (GNGC) is being used to cap and stabilize a 178000 m(exp 2) heap-leach pad at the Summitville Mine Superfund Site in Colorado. Selected were materials on the basis of design requirements for permeability, strength, extreme site conditions and cost. The Summitville cleanup called for a heap-leach pad cap to provide a barrier that would prevent precipitation from infiltrating the pad material. This long-term remediation prevents the pile from becoming saturated and allowing water to overflow the downslope dike, which could cause instability to dike and pond. Three geosynthetic alternatives were proposed. The contractor, that was awarded the heap leach pad, phase 2 contract, decided for a geosynthetic clay liner cap placed directly on the redesigned slopes. Bentofix NW-8 was used as GCL and TexNet TN was selected as the geocomposite drain. Conformance testing, subgrade preparation review, geosynthetic installation/repair inspection and review of cover material placement, performed by independent construction-quality assurance, showed that GCL is a well-suited cap material for heap leach pads, where high wind, cold temperatures rain and high altitude hinder construction. The robust geosynthetic allowed on-site coarse material to be used in the subgrade and cover layer, which saved the cost of importing more expensive bedding material.
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