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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Brown, A. (1995). Geohydrology and adit plugging. In H. H. Posey, J. A. Pendleton, & D. J. A. Van Zyl (Eds.), Special Publication – Colorado Geological Survey, Report: 38 (pp. 87–98). Proceedings; Summitville forum '95.
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Demchak, J., Morrow, T., Skousen, J., Donovan, J. J., & Rose, A. W. (2001). Treatment of acid mine drainage by four vertical flow wetlands in Pennsylvania Evolution and remediation of acid-sulfate groundwater systems at reclaimed mine-sites. Geochemistry – Exploration, Environment, Analysis, 1(1), 71–80.
Abstract: Acid mine drainage (AMD) is a serious problem in many watersheds where coal is mined. Passive treatments, such as wetlands and anoxic limestone drains (ALDs), have been developed, but these technologies show varying treatment efficiencies. A new passive treatment technique is a vertical flow wetland or successive alkalinity producing system (SAPS). Four SAPS in Pennsylvania were studied to determine changes in water chemistry from inflow to outflow. The Howe Bridge SAPS removed about 130 mg l (super -1) (40%) of the inflow acidity concentration and about 100 mg l (super -1) (60%) iron (Fe). The Filson 1 SAPS removed 68 mg l (super -1) (26%) acidity, 20 mg l (super -1) (83%) Fe and 6 mg l (super -1) (35%) aluminium (Al). The Sommerville SAPS removed 112 mg l (super -1) (31%) acidity, exported Fe, and removed 13 mg l (super -1) (30%) Al. The McKinley SAPS removed 54 mg l (super -1) (91%) acidity and 5 mg l (super -1) (90%) Fe. Acid removal rates at our four sites were 17 (HB), 52 (Filson1), 18 (Sommerville) and 11 (McKinley) g of acid per m (super 2) of surface wetland area per day (g/m (super 2) d (super -1) ). Calcium (Ca) concentrations in the SAPS effluents were increased between 8 and 57 mg l (super -1) at these sites. Equilibrators, which were inserted into compost layers to evaluate redox conditions at our sites, showed that reducing conditions were generally found at 60 cm compost depths and oxidized conditions were found at 30 cm compost depths. Deeply oxidized zones substantiated observations that channel flow was occurring through some parts of the compost. The Howe Bridge site has not declined in treatment efficiency over a six year treatment life. The SAPS construction costs were equal to about seven years of NaOH chemical treatment costs and 30 years of lime treatment costs. So, if the SAPS treatment longevity is seven years or greater and comparable effluent water quality was achieved, the SAPS construction was cost effective compared to NaOH chemical treatment. Construction recommendations for SAPS include a minimum of 50 cm of compost thickness, periodic replacement or addition of fresh compost material, and increasing the number of drainage pipes underlying the limestone.
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Fischer, R., Reissig, H., Gockel, G., Seidel, K. H., & Guderitz, T. (1998). Direkte Neutralisation und Untergrundwasserbehandlung des Restwassers im Tagebaurestsee Heide VI. Direct neutralization and treatment of deep subsoil water of the residual water in the open-pit relic lake Heide VI. Braunkohle, Surface Mining, 50(3), 273–278.
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Guo, F., & Yu, H. (1993). Hydrogeochemistry and treatment of acid mine drainage in southern China. In B. A. Zamora, & R. E. Connolly (Eds.), Proceedings of the Annual National Meeting – American Society for Surface Mining and Reclamation, vol.10 (pp. 277–283). The challenge of integrating diverse perspectives in reclamation.
Abstract: Coal mines and various sulfide ore deposits are widely distributed in Southern China. Acid mine drainage associated with coal and metal sulfide deposits affects water quality in some mined areas of Southern China. Mining operations accelerate this natural deterioration of water quality by exposing greater surface areas of reactive minerals to the weathering effects of the atmosphere, hydrosphere, and biosphere. Some approaches to reduce the effects of acid mine drainage on water quality are adopted, and they can be divided into two aspects: (a) Man-made control technology based on long-term monitoring of acid mine drainage; and, (b) Neutralization of acidity through the addition of lime. It is important that metals in the waste water are removed in the process of neutralization. A new method for calculating neutralization dosage is applied. It is demonstrated that the calculated value is approximately equal to the actual required value.
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