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Bolzicco, J., Carrera, J., & Ayora, C. (2004). Eficiencia de la barrera permeable reactiva de Aznalcollar (Sevilla, Espana) como remedio de aguas acidas de mina. Reactive permeable disposal barrier at Aznalcollar Mine, Seville, Spain; as remediation for acid mine drainage. Revista Latino-Americana de Hidrogeologia, 4, 27–34.
Abstract: As a result of the collapse of a mine tailing dam in april 1998 about 40 km of the Agrio and Guadiamar valleys were covered with a layer of pyrite sludge. Although most of the sludge was removed, a small amount remains in the soil of the Agrio valley and the aquifer remains polluted with acid water (ph<4) and metals (10 mg/L Zn, 5 mg/L Cu and Al). A permeable reactive barrier was build across the aquifer to increase the alcalinity and retain the metals. The barrier is made up of three sections of 30 m longX1.4 m thickX5 m deep (average) containing different proportions of limestone gravel, organic compost and zero-valent iron. The residence time of the water in the barrier is about two days. Within the barrier, the pH values increase to near neutral mainly due to calcite dissolution. Metals co-precipitate as oxyhydroxides, and they are also adsorbed on the organic matter surface. Down-stream the barrier, the total pollution removal is around 60-90% for Zn and Cu, and from 50 to 90% for Al and acidity.
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Berthelot, D., & Haggis, M. (1999). Application of remote monitoring and data management systems to environmental management of tailings facilities. In D. Goldsack, N. Belzile, P. Yearwood, & G. Hall (Eds.), Sudbury '99; Mining and the environment II; conference proceedings.
Abstract: The mining industry has made tremendous strides in the last 20 years in the prevention and control of acid mine drainage. However, there remain a number of circumstances where the long-term operation, care and maintenance of tailings management facilities will be required. The application of progressive environmental technologies and management systems is key to cost control and environmental liability management at these sites. Mine Waste Management Inc. currently operates Rio Algom Limited's five effluent treatment plants and seven waste management areas in the Elliot Lake, Ontario region using a Remote Plant Monitoring and Control Network (RPMCN). This system, based on Intellutions's “Fix 32” technology, enables the monitoring and control of these plants from a centralized location thus reducing labour costs while providing 24-hour surveillance. Scheduling, auditing and reporting of plant operating and environmental monitoring programs are integrated and controlled using the Envista (super TM) environmental information management system. Proper application of these technologies and management systems facilitates delivery of cost-effective environmental monitoring, and care and maintenance programs at these sites and provides tools to demonstrate compliance with all environmental performance criteria.
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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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Benzaazoua, M., & Bussiere, B. (1999). Desulphurization of tailings with low neutralizing potential; kinetic study and flotation modeling. In D. Goldsack, N. Belzile, P. Yearwood, & G. Hall (Eds.), Sudbury '99; Mining and the environment II; conference proceedings.
Abstract: Environmental desulphurization is an attractive alternative for acid generating tailings management as demonstrated during the last few years. In fact, such process placed at the end of the primary treatment circuit allows to reduce greatly the amount of problematic tailings by concentrating the sulphidic fraction. Moreover, the desulphurized tailings (non-acid generating) have the geotechnical and environmental properties for being used as fine material in a cover with capillary barrier effects. To produce desulphurized tailings, non selective froth flotation is the most adapted method as shown in many previous works. Desulphurization level is fixed by tailings sulphur content (or sulphide content) and neutralization potential NP. The final residue should have enough NP to compensate for his acid generating potential AP. In this paper, the authors present the results of laboratory tests conducted in Denver cells for studying the sulphide flotation kinetics of four mine tailings which are characterized by a weak neutralization potential (under 37 kg CaCO (sub 3) /t). Tailings 1, 2, 3 and 4 contain respectively 5.27, 10, 4.25 and 16.9 sulphur Wt. %. Tailings 1 and 2 are cyanide free and are well floated at pH around 11 by using amyl xanthate as collector. Collector dosage was optimized for these tailings and the results show that Tailing 2 need more collector. However, Tailings 3 and 4, which come from a gold cyanidation process, could not provide good sulphide recovery with xanthate collector because of the pyrite depression. To overcome this problem, amine acetate was used successfully but induces important entrainment. The consumption of this collector was also optimized. The results of kinetic tests and collector dosage were combined and modeled to establish relationships which allow to estimate the desulphurization performances.
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Anonymous, & Kontopoulos, A. (1998). Acid mine drainage control. In S. H. Castro, F. Vergara, & M. A. Sanchez (Eds.), Effluent treatment in the mining industry. Concepcion: University of Concepcion.
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