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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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Bennett, J. W., Timms, G. P., & Ritchie, A. I. M. (1999). The effectiveness of the covers on waste rock dumps at Rum Jungle and the impact in the long term. Mining into the next century : environmental opportunities and challenges Proceedings of the 24th annual environmental workshop Townsville October, , 379–388.
Abstract: Covers are widely used as a means of controlling pollutant generation from sulfidic waste piles. To date, there has been little data available to test the effectiveness of such covers. Monitoring of two waste rock dumps at Rum Jungle over more than fifteen years has provided the opportunity to assess cover effectiveness in the medium term. For the first 9 years the infiltration rate through the cover on Whites dump was less than the design figure of 5 per cent of rainfall. In subsequent years, however, the rate has increased to between 5 and 10 per cent. In the first six years the infiltration rate through the cover on Intermediate dump was also less than 5 per cent. Unfortunately, further measurements had to be abandoned due to equipment malfunction in this dump. Oxygen and temperature profiles measured below the cover have been used to estimate the overall oxidation rate in the two dumps. This is between 30 and 50 per cent of the oxidation rate prior to installation of the cover. The effect these results have on pollutant loads in drainage in the long term depends on the nature of the control mechanisms in the system. If pollutant concentrations in drainage are determined by secondary mineralisation within the dumps then pollutant loads in the long term will be essentially proportional to any further increase in the infiltration rate. If the pollutant loads in drainage are largely determined by the overall oxidation rates then we can expect the pollutant loads from the two dumps to increase in the long term to a level about one third to one half of that prior to rehabilitation. In this context, 'long term' means about 40 years after installation of the cover system. Given the implications this work has for the use of soil covers, the following additional studies should be undertaken: A measurement program to quantify the pollution loads from Intermediate and Whites waste rock dumps. A program of computation, backed by acquisition of mineralogical data on the wastes, to address the question of controls on concentration and load in effluent from the two dumps. A program to determine the reason for the deteriorating performance of the covers at Rum Jungle.
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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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Bernoth, L., Firth, I., McAllister, P., & Rhodes, S. (2000). Biotechnologies for Remediation and Pollution Control in the Mining Industry. Miner. Metall. Process., 17(2), 105–111.
Abstract: As biotechnologies emerge from laboratories into main-stream application, the benefits they, offer are judged against competing technologies and business criteria. Bioremediation technologies have passed this test and are now widely used for the remediation of contaminated soils and ground waters. Bioremediation includes several distinct techniques that are used for the treatment of excavated soil and includes other techniques that are used for in situ applications. They play an important and growingrole in the mining industry for cost-effective waste management and site remediation. Most applications have been for petroleum contaminants, but advances continue to be made in the treatment of more difficult organ ic and inorganic species. This paper discusses the role of biotechnologies in remediation and pollution control from a mining-industry perspective. Several case studies are presented, including the land application of oily wastewater from maintenance workshops, the composting of hydrocarbon-contaminated soils and sludges, the bioventing of hydrocarbon solvents, the intrinsic bioremediation of diesel hydrocarbons, the biotreatment of cyanide in water front a gold mine, and the removal of manganese from acidic mine drainage.
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Berthelot, D., Haggis, M., Payne, R., McClarty, D., & Courtain, M. (1999). Application of water covers, remote monitoring and data management systems to environmental management at uranium tailings sites in the Serpent River Watershed. CIM Bull., 92(1033), 70–77.
Abstract: Over forty years of uranium mining in the Elliot lake region of Ontario (1956-1996) has resulted in the production of over 300 million pounds of uranium. With the completion of mining activity Rio Algom limited and Denison Mines limited are utilizing progressive environmental technologies and management systems to reduce and manage the environmental risks associated with the 150 million tonnes of potentially acid-generating tailings in nine regional waste management areas. Water covers designed to reduce oxygen entry and, thereby, significantly inhibit acid generation, have been applied at six of the sites with the Quirke site serving as a demonstration site for the Mine Environmental Neutral Drainage program, All five of Rio Algom limited's effluent treatment plants are monitored and controlled from a central control station utilizing a Supervisory Control and Data Acquisition (SCADA) system based on “Fix Dmacs” technology Scheduling, auditing and reporting of plant operating and environmental monitoring programs for the entire watershed are controlled utilizing the Regional Environmental Information Management System (REIMS). Proper application of these technologies and management systems facilitates delivery of cost-effective environmental monitoring, care and maintenance programs at these sites and provides tools to demonstrate compliance with all environmental performance criteria.
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