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Fisher, T. S. R., & Lawrence, G. A. (2006). Treatment of acid rock drainage in a meromictic mine pit lake. Journal of environmental engineering, 132(4), 515–526.
Abstract: The Island Copper Mine pit near Port Hardy, Vancouver Island, B.C., Canada, was flooded in 1996 with seawater and capped with fresh water to form a meromictic (permanently stratified) pit lake of maximum depth 350 m and surface area 1.72 km2. The pit lake is being developed as a treatment system for acid rock drainage. The physical structure and water quality has developed into three distinct layers: a brackish and well-mixed upper layer; a plume stirred intermediate layer; and a thermally convecting lower layer. Concentrations of dissolved metals have been maintained well below permit limits by fertilization of the surface waters. The initial mine closure plan proposed removal of heavy metals by metal-sulfide precipitation via anaerobic sulfate-reducing bacteria, once anoxic conditions were established in the intermediate and lower layers. Anoxia has been achieved in the lower layer, but oxygen consumption rates have been less than initially predicted, and anoxia has yet to be achieved in the intermediate layer. If anoxia can be permanently established in the intermediate layer then biogeochemical removal rates may be high enough that fertilization may no longer be necessary. < copyright > 2006 ASCE.
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Henderson, A. (1998). The implementation of paste fill at the Henty Gold Mine. Minefill'98, 98(1), 299–304.
Abstract: The Henty Gold Mine, located ill Western Tasmania uses innovative solutions to effectively manage a mining operation in an environmentally sensitive setting and has been presented with several environmental awards. Fill is required as part of the mining method to provide passive ground support, minimise rock exposure and ensure maximum recovery of the small but high-grade orebody. The use of the whole portion of leach residue in the backfill reduces the surface tailing disposal requirements. Therefore, High Density Paste Fill (HDPF) has been selected as the most appropriate fill method to meet these objectives. Additional benefits include the minimisation of excess water from fill and the subsequent need for the collection and treatment of water and slimes. There are minimal equipment requirements during placement, thereby optimising mine resources for production.
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Landers, J. (2006). Bioremediation method could cut cost of treating acid rock drainage. Civil Engineering, 76(7), 30–31.
Abstract: The Gilt Edge Mine in South Dakota's Lawrence County was a gold mine that was abandoned later when its recent owner went bankrupt. Seeking a cost-effective method for treating millions of gallons of acid rock drainage (ARD), CDM partnered with Green World Science, Inc. (GWS) of Boise, Idaho, for the development of an in situ bioremediation process that can be used to remove metals from pit lake water. Recent testing revealed that the in situ bioremediation method can successfully remove metals from highly acidic water without the need to construct costly water treatment facilities.
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Gobla, M. J. (2002). A rapid response to cleanup – Gilt Edge Superfund Site, South Dakota. Tailings and Mine Waste '02, , 421–425.
Abstract: The Gilt Edge gold mine is an acid drainage site that has been put on an accelerated closure schedule. The mine ceased activities in 1999 when Dakota Mining Corporation declared bankruptcy forcing the State of South Dakota to immediatly assume water treatment operations. Evaluation of conceptual closure plan options and cost estimates led the State of South Dakota to a decision to seek Federal assistance. The site has quickly moved into reclamation mode for the principal contamination source, the Ruby waste-rock dump. Designs and specifications for capping the Ruby waste-rock dump were prepared while Superfund listing was pursued. In October of 2000, mobilization of the first reclamation contractor began and by December the site was added to the National Priorities List. Capping the waste-rock dump will address a major acid drainage source. Water treatment requirements are expected to decline as conventional methods such as diverting clean water, backfilling, grading, capping, limestone neutralization, and revegetation are implemented. Acid seepage from underground workings, steep highwalls, and some pit backfills will remain. Major field trials of emerging technologies are nearing completion and some are showing promising results. Carbon reduction in a pit lake, and pyrite microencapsulation on simulated waste dumps, are showing initial success. Their application may minimize or eliminate the need for long-term active water treatment which has been a long sought goal for major acid rock drainage sites.
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Michaud, L. H. (1994). Recent technology related to the treatment of acid drainage. Earth and Mineral Sciences, 63(3), 53–55.
Abstract: The generation of acid mine drainage is a serious environmental problem associated with coal mining. The chemistry of acid mine drainage is outlined. The prevention and minimization of acid mine drainage formation is examined. The in situ inhibition and remediation of acid mine drainage is described. Methods for the passive treatment of acid mine drainage after formation are discussed. The design of treatment systems is considered. -P.M.Taylor
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