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Cram, J. C. (1996). Diversion well treatment of acid water, Lick Creek, Tioga County, PA. Ph.D. thesis, Pennsylvania State University at University Park,, University Park.
Abstract: Diversion wells implement a fluidized bed of limestone for the treatment of acid water resulting from acid mine drainage or acid precipitation. This study was undertaken to better understand the operation of diversion wells and to define the physical and chemical factors having the greatest impact on the neutralization performance of the system. The study site was located near Lick Creek, a tributary stream of Babb Creek, near the Village of Arnot in Tioga County, Pennsylvania. Investigative methods included collection and analysis of site water quality and limestone data and field study of this as well as other diversion well sites. Analysis of data led to these general conclusions: The site received surface water influenced by three primary sources 1) precipitation, 2) mine drainage baseflow, and 3) melted snow. Water mostly influenced by precipitation events and mine drainage baseflow was more acidic than water influenced by melting snow conditions. The diversion wells were generally able to treat only half or less of the total stream flow of Lick Creek and under extremely high flow conditions the treatment provided was minimal. A range of flow conditions were identified which produced the best performance for the two diversion wells. Treatment produced by the system decreased through the loading cycle and increases to a maximum value after each weekly refilling of limestone. Fine grained sediment in the stream was found to be limestone of the same general composition as the material placed within the wells. Neutralization of acid water was largely due to microscopic particles rather than the limestone sediment discharged to the stream. Additional downstream buffering due to the limestone sediment physically discharged from the vessels was not apparent. Diversion well systems are inexpensive and simple to construct. In addition, the systems were found to be highly reliable and able to effectively treat acid water resulting from mine drainage and acid precipitation. Diversion wells provide better treatment when the treatment site is located at the source of the acidity (such as a mine discharge), rather than at the receiving stream. Systems should be designed with 15 to 20 feet of hydraulic head and the site must have year-round access. Diversion well systems require weekly addition of limestone gravel to the vessels to facilitate continual treatment. A great deal of commitment is necessary to maintain a diversion well system for long periods of time. These systems are more economical and require less attention that conventional chemical treatment of acid water. However, these systems require more attention that traditional passive treatment methods for treatment of acid, including mine drainage.
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Crawford, G. A. (1995). Environmental Improvements by the Mining-industry in the Sudbury Basin of Canada. J. Geochem. Explor., 52(1-2), 267–284.
Abstract: Responsible mining companies have done much to redress the environmental damage of earlier technologies and continue to do more. In the Sudbury Basin, one of the most important mining areas in the world, both Inco Limited and Falconbridge Limited, two of the largest nickel producers, have significantly decreased sulphur dioxide emissions in the last 40 years from substantially 100% to about 10% or less of the sulphur in the ore; decreased water effluents by recycling; treated effluents to comply with government regulations; revegetated mine rock and surface tailings deposits and rehabilitated landscapes in the surrounding communities. Inco and Falconbridge continue to develop improved means for environmentally sound handling of all wastes including recycling and to reclaim land at abandoned mine sites. They have developed and implemented environmental policies and codes of practice, not only to comply with regulations, but to anticipate them. The mining industry recognizes the need for regulation to protect human health and the environment. Existing regulations are based on a hazard assessment approach. A more realistic, pragmatic and cost-effective basis for regulation is risk management. This relates any documented effects to measured exposures and recognizes the need for exposure levels low enough that incidence of adverse health effects is as low as in the surrounding ecosystem.
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Curi, A. C., Granda, W. J. V., Lima, H. M., & Sousa, W. T. (2006). Zeolites and their application in the decontamination of mine waste water. Informacion Tecnologica, 17(6), 111–118.
Abstract: This paper describes the genesis, structure and classification of natural zeolites, including their most relevant properties such as porosity, adsorption and ionic exchange. The use of natural zeolites in the treatment of effluents containing heavy metals is reviewed based on current literature. These uses are focused on mineral-metallurgical effluents and mercury pollution related to artisan mining activities. The study shows that natural zeolites are efficient in removal of heavy metals in metal mining effluents, can be produced and improved at a low cost, and can also be used to adsorb mercury vapors from ovens used to fire amalgams.
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Davies, G. J., Holmes, M., Wireman, M., King, K., Gertson, J. N., & Stefanic, J. M. (2001). Water tracing at scales of hours to decades as an aid to estimating hydraulic characteristics of the Leadville Mine drainage tunnel.
Abstract: The Leadville Mine Drainage Tunnel (LMDT) is a 3.3 kilometer structure that was constructed in the complicated geology of the Leadville mine district in the 1940's. Discharge from the LMDT is impacted by heavy metals and is treated at a plant built in 1992 operated by the United States Bureau of Reclamation. On the surface waste rock and other remnants of the mining operations litter the landscape and this material is exposed to precipitation. As a result of contact with this material, surface water often has pH of less than 3 and its containment and disposal is necessary before it impacts surface drainage and the nearby Arkansas River. Using a borehole drilled into the mine workings the U.S. EPA has devised a plan in which the impacted water is contained on the surface which then can be discharged into the mine workings to discharge from the LMDT and be treated. The percentage of water discharging from the mining district along the drainage tunnel is unknown, and since there is no access, information about the condition of the tunnel with regards to blockages is also relatively obscure. Application of quantitative water tracing using fluorescent dyes was used to model the flow parameters at the scale of hours in the tunnel and evaluate the likelihood of blockages. Because the tunnel has intersected several lithologies and faults, other locations such as discharging shafts, adits and surface streams that could be hydraulically connected to the LMDT were also monitored. An initial tracer experiment was done using an instantaneous injection, which was followed by additional injections of water. Another tracer injection was done when there was a continuous flow of impacted water into the workings. Analysis of the tracer concentration responses at water-filled shafts and at the portal were used to model the flow along the tunnel and estimate several hydraulic parameters. Waters in these settings are mixtures of components with different residence times, so, qualitative tritium data were used to evaluate residence times of decades. The combined injected tracer and tritium data as well as other geochemical data were used to infer the nature of flow and recharge into the tunnel.
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Davis, L. (1994). A handbook of constructed wetlands: a guide to creating wetlands for: agricultural wastewater, domestic wastewater, coal mine drainage, stormwater in the Mid-Atlantic Region.
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