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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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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Ballivy, G., & Bienvenu, L. (1998). Stabilisation des rejets miniers a l'aide de rejets de cimenterie. Stabilization of mining wastes using cement factory wastes Activites de recherche du Ministere des Ressources Naturelles du Quebec sur le drainage minier acide; rapport 1997-1998. Research activities of the Quebec Natural Resources Ministry on acid mine drainage; report 1997-1998 (Vol. Rn 98-5034).
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LaPointe, F., Fytas, K., & McConchie, D. (2005). Using permeable reactive barriers for the treatment of acid rock drainage. International journal of surface mining, reclamation and environment, 19(1), 57–65.
Abstract: Acid mine drainage (AMD) is the most serious environmental problem facing the Canadian mineral industry today. It results from oxidation of sulphide minerals (e.g. pyrite or pyrrhotite) contained in mine waste or mine tailings and is characterized by acid effluents rich in heavy metals that are released into the environment. A new acid remediation technology is presented, by which metallurgical residues from the aluminium extraction industry are used to construct permeable reactive barriers (PRBs) to treat acid mine effluents. This technology is very promising for treating acid mine effluents in order to decrease their harmful environmental effects
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Sanders, F., Rahe, J., Pastor, D., & Anderson, R. (1999). Wetlands treat mine runoff. Civil Engineering, 69(1), 53–55.
Abstract: In the late 1890s, silver, lead and zinc deposits were discovered along the headwaters of the Blackfoot River, northeast of Missoula, Mont. Settlers began mining the metals in earnest, and eventually the mines became known as the Upper Blackfoot Mining Complex (UBMC). Many of the mines were operated long enough to supply metals for World War II weaponry, but after the war the mines were abandoned, and by the 1960s, their orange-tainted runoff began to concern both passersby and state officials. In 1991, the state contacted the current owners of several of those mines-including the Mike Horse and the Anaconda-to negotiate a voluntary cleanup. The American Smelting and Refining Co. (ASARCO) and the Atlantic Richfield Co. (ARCO) agreed to remediate the sites' metal-enriched, moderately to severely acidic drainage, which was discharging into the upper Blackfoot River. As part of effort to reclaim the Mike Horse and Anaconda mines, engineers with McCulley, Frick and Gilman Inc. (MFG), Boulder, Colo., developed an integrated, passive wetland treatment system that will take several years to reach full treatment capacity in the high-elevation environment, but will last for decades. (Constructed and restored wetlands have also been part of the remediation of other UBMC mines, such as the Carbonate and Paymaster mines.) The Mike Horse and Anaconda system, designed to meet National Pollutant Discharge Elimination Systems (NPDES) restrictions, concentrates primarily on zinc and iron and, to a lesser extent, on copper, lead and other metals.
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