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Arnekleiv, J. V. (1995). Downstream Effects Of Mine Drainage On Benthos And Fish In A Norwegian River – A Comparison Of The Situation Before And After River Rehabilitation. Journal of Geochemical Exploration, 52(1-2), 35–43.
Abstract: Parts of the Norwegian river Gaula are strongly polluted from former mining activity in the area. In the most polluted parts of the river the concentration levels of Cu and Zn in 1986-1987 were up to 155 mug l-1 and 186 mug l-1, respectively. In 1989 the spoil heaps in the mining area were covered with protective layers of moss-covered plastic. In 1991-1992 the concentration levels of Cu and Zn had decreased by 75% and 65%, respectively. Animal life in the polluted area seemed to be strongly affected by the trace metals in 1986-1987. The 1991-1992 results showed a marked increase in the number of species and in the number of individuals of each species of Ephemeroptera and Plecoptera, compared with the results from 1986-87. Good correlations were found between the concentrations of Cu in the water and both the number of species and the number of individuals of Ephemeroptera and Plecoptera. Analysis of the species Baetis rhodani, Diura nanseni and Rhyacophila nubila showed an average total dry weight content of Cu up to 264 mug g-1, of Zn up to 1930 mug g-1 and of Cd up to 16 mug g-1. The contents of the three trace metals were significantly different from one species to another and in part between the stations for each species. In 1987 trout died after an exposure of one to two days on three test sites in the river, whereas in 1991-1992 40-75% of the trout survived an exposure period of several weeks at two of the sites. Electrofishing in 1991-1992 indicated recolonization of trout in the lower parts of the former affected and uninhabitable area.
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Guay, R. (1999). Effect of flooding of oxidized mine tailings on T-ferrooxidans and T-thiooxidans survival and acid mine drainage production: a 4 year restoration-environmental follow-up. Biohydrometallurgy and the Environment toward the Mining of the 21st Century, Pt B 1999, 9, 635–643.
Abstract: A pilot-scale study on the effect of flooding unoxidized and oxidized Cu/Zn tailings demonstrated the technical feasability of this technology to remediate a mining site where over 3 million tons of tailings were impounded. Full-scale flooding of the tailing pond with free running water was undertaken after the construction of an impervious dam; approximately 2 million m(3) of surface water at pH 7,4 completely covered the tailings after 16 months. The minimal water column over the tailings was established at 1,20 m and reached 4,5 m, depending on the site topography. Water and tailings samples were collected from 9 different locations from the surface of the man-made lake using a specially designed borer and were analyzed for pH, conductivity, iron- and sulfur-oxidizing bacteria activity and numbers as well as the sulfate reducing bacteria (SRB) population. We showed that over a four year period of flooding, the overall population of iron-oxidizers decreased considerably; their numbers drastically fell from 1 x 10(6) to 1 x 10(2) active cells per g of oxidized tailings while the SRBs increased from 10(1) to 10(5)/g. The pH of the influent, the reservoir and the effluent water remained fairly constant between 6,9 up to 7,4 over the entire period. During this time, interstitial water pH increased from 2,9 to 4,3 in flooded tailings where lime could not be incorporated in the first 20 cm of tailings; elsewhere, the pH of the tailings suspensions remained fairly constant around neutral values (pH 7,0). Dissolved oxygen was measured at fixed intervals and remained also constant between 6 and 7.5 mg/L while water temperatures fluctuated below freezing point to +20C respectively in winter and summer season.
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Jarvis, A. P. (2006). Effective remediation of grossly polluted acidic, and metal-rich, spoil heap drainage using a novel, low-cost, permeable reactive barrier in Northumberland, UK. Environmental Pollution, 143(2), 261–268.
Abstract: A permeable reactive barrier (PRB) for remediation of coal spoil heap drainage in Northumberland, UK, is described. The drainage has typical chemical characteristics of pH < 4, [acidity] > 1400 mg/L as CaCO3, [Fe] > 300 mg/L, [Mn] > 165 mg/L, [Al] > 100 mg/L and IS041 > 6500 mg/L. During 2 years of operation the PRB has typically removed 50% of the iron and 40% of the sulphate from this subsurface spoil drainage. Bacterial sulphate reduction appears to be a key process of this remediation. Treatment of the effluent from the PRB results in further attenuation; overall reductions in iron and sulphate concentrations are 95% and 67% respectively, and acidity concentration is reduced by an order of magnitude. The mechanisms of attenuation of these, and other, contaminants in the drainage are discussed. Future research and operational objectives for this novel, low-cost, treatment system are also outlined. (c) 2005 Elsevier Ltd. All rights reserved.
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Norris, R. H. (1987). Effectiveness Of Mine Rehabilitation In Relation To Water-Quality. Acta Biologica Hungarica, 38(1), 127–139.
Abstract: When mining is completed the sites may be completely restored to the originalecosystem, rehabilitated for some desirable environmental characteristics, desirable alternative ecosystemscreated or just neglected. The strategy adopted will depend on the intended uses of the parts of theenvironment (including water) affected by the mining. An example of rehabilitation of a metal mine nearthe Australian Federal Capital is used to illustrate the problems that may be encountered. These include:lack of controls while mining is underway; catastrophic events, such as the collapse of a settling dam,lack of site specific understanding of pyrite oxidation processes, particularly those that are biologicallyenhanced; the need for adequate biological information on which to base decisions to meet biologicalinformation on which to base decisions to meet biological objectives. Experience has shown that biologicalcollections such studies should be stored in museums where they will be valuable for comparisons of changesover long periods.
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Orava, D. (1995). Evaluating alternative long-term strategies for treatment of acid mime drainage (AMD). Sudbury '95 – Mining and the Environment, Conference Proceedings, Vols 1-3, , 505–514.
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