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Carlson, L., & Kumpulainen, S. (2001). Retention of harmful elements by ochreous precipitates of iron. Tutkimusraportti Geologian Tutkimuskeskus, -(154), 30–33.
Abstract: The capability of soil fines to fix harmful elements, e.g. heavy metals and arsenic, depends on specific surface area and other characteristics, such as surface charge. In the pH-range typical of natural waters (pH 5,5-7,5), the surfaces of fine-grained silicate particles and manganese oxides are negatively charged; consequently cations, such as heavy metals, fix effectively to them. The iron oxide surfaces are usually positively charged and typically fix anions, such as sulphate and arsenate. Retention of anions is especially extensive to precipitates formed from acid mine drainage (pH 2,5-5,0). For example, precipitates found at Paroistenjarvi mine, Finland, contain more than 70 g/kg of arsenic (dry matter). Adsorbed anions, e.g. sulphate, enhance the capacity of precipitate to fix heavy metal cations in low-pH environments.
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Benner, S. G., Blowes, D. W., & Ptacek, C. J. (1997). A full-scale porous reactive wall for prevention of acid mine drainage. Ground Water Monitoring and Remediation, 17(4), 99–107.
Abstract: The generation and release of acidic drainage containing high concentrations of dissolved metals from decommissioned mine wastes is an environmental problem of international scale. A potential solution to many acid drainage problem is the installation of permeable reactive walls into aquifers affected by drainage water derived from mine waste materials. A permeable reactive wall installed into an aquifer impacted by low-quality mine drainage waters was installed in August 1995 at the Nickel Rim mine site near Sudbury, Ontario. The reactive mixture, containing organic matter, was designed to promote bacterially mediated sulfate reduction and subsequent metal sulfide precipitation. The reactive wall is installed to an average depth of 12 feet (3.6 m) and is 49 feet (15 m) long perpendicular to ground water flow. The wall thickness (flow path length) is 13 feet (4 m). Initial results, collected nine months after installation, indicate that sulfate reduction and metal sulfide precipitation is occurring. Comparing water entering the wall to treated water existing the wall, sulfate concentrations decrease from 2400 to 4600 mg/L to 200 to 3600 mg/L; Fe concentration decrease from 250 to 1300 mg/L to 1.0 to 40 mg/L, pH increases from 5.8 to 7.0; and alkalinity (as CaCO<inf>3</inf>) increases from 0 to 50 mg/L to 600 to 2000 mg/L. The reactive wall has effectively removed the capacity of the ground water to generate acidity on discharge to the surface. Calculations based on comparison to previously run laboratory column experiments indicate that the reactive wall has potential to remain effective for at least 15 years.
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Janiak, H. (1992). Mine drainage treatment in Polish lignite mining. Mine Water Env., 11(1), 35–44.
Abstract: The paper presents volumes and characteristics of water discharged from some Polish lignite open pit mines and discusses methods for its treatment. Results of research work concerned with increase in mine drainage efficiency by using processes of radiation, flocculation and filtration through a set of bog plants, iknown as grass filter are also discussed
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Ketellapper, V. L., Williams, L. O., Bell, R. S., & Cramer, M. H. (1996). The control of acid mine drainage at the Summitville Mine Superfund Site. In Proceedings of the Symposium on the Application of Geophysics to Environmental and Engineering Problems (SAGEEP), vol.1996 (pp. 303–311).
Abstract: The Summitville Mine Superfund Site is located about 25 miles south of Del Norte, Colorado, in Rio Grande County. Occurring at an average elevation of 11,500 feet in the San Juan Mountain Range, the mine site is located two miles east of the Continental Divide. Mining at Summitville has occurred since 1870. The mine was most recently operated by Summitville Consolidated Mining Company, Inc. (SCMCI) as an open pit gold mine with extraction by means of a cyanide leaching process. In December of 1992, SCMCI declared bankruptcy and vacated the mine site. At that time, the US Environmental Protection Agency (EPA) took over operations of the water treatment facilities to prevent a catastrophic release of cyanide and metal-laden water from the mine site. Due to high operational costs of water treatment (approximately $50,000 per day), EPA established a goal to minimize active water treatment by reducing or eliminating acid mine drainage (AMD). All of the sources of AMD generation on the mine site were evaluated and prioritized. Of the twelve areas identified as sources of AMD, the Cropsy Waste Pile, the Summitville Dam Impoundment, the Beaver Mud Dump, the Reynolds and Chandler adits, and the Mine Pits were consider to be the most significant contributors to the generation of metal-laden acidic (low pH) water. A two part plan was developed to control AMD from the most significant sources. The first part was initiated immediately to control AMD being released from the Site. This part focused on improving the efficiency of the water treatment facilities and controlling the AMD discharges from the mine drainage adits. The discharges from the adits was accomplished by plugging the Reynolds and Chandler adits. The second part of the plan was aimed at reducing the AMD generated in groundwater and surface water runoff from the mine wastes. A lined and capped repository located in the mine pits for acid generating mining waste and water treatment plant sludge was found to be the most feasible alternative. Beginning in 1993, mining wastes which were the most significant sources of AMD were being excavated and placed in the Mine Pits. In November 1995, all of the waste from these sources had been excavated and placed in the the Mine Pits. This paper discusses EPA's overall approach to stabilize on-site sources sufficiently such that aquatic, agricultural, and drinking water uses in the Alamosa watershed are restored and/or maintained with minimal water treatment.
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Berg, G. J., & Arthur, B. (1999). Proposed mine water treatment in Wisconsin. In D. Goldsack, N. Belzile, P. Yearwood, & G. J. Hall (Eds.), Sudbury '99; mining and the environment II; Conference proceedings. Sudbury: Sudbury Environmental.
Abstract: Water quality standards are driving wastewater effluent limits to ultra-low levels in the nanogram/L range. Standards are proposed that require discharges to match background water quality. The new ultra-low level standards require cautious sampling techniques, super clean laboratory methods and more advanced treatment technologies. This paper follows a case history through water quality standards for ultra-low metals, laboratory selection, and the design of a wastewater treatment system that can meet the water quality standards which are required to permit a proposed copper and zinc mine in Northern Wisconsin. A high degree of care must be taken when sampling for ultra-low level metals. Both surface water and treated effluent samples present new challenges. Sampling methods used must assure that there are no unwanted contaminants being introduced to the samples. The selection of a laboratory is as critical as the construction of a state of the art wastewater treatment system. Treatment methods such as lime and sulfide precipitation have had a high degree of success, but they do have limitations. Given today's ultra-low standards, it is necessary to assess the ability of reverse osmosis, deionization, and evaporation to provide the high level of treatment required.
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