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Banks, S. B. (2003). The UK coal authority minewater-treatment scheme programme: Performance of operational systems. Jciwem, 17(2), 117–122.
Abstract: This paper summarises the performance of minewater-treatment schemes which are operated under the Coal Authority's National Minewater Treatment Programme. Commonly-used design criteria and performance indicators are briefly discussed, and the performance of wetland systems which are operated by the Coal Authority is reviewed. Most schemes for which data are available remove more than 90% iron, and average area-adjusted iron-removal rates range from 1.5 to 5.5 g Fe/m(2). d. These values, which are based on performance calculations, can be distorted by several factors, including the practice of maximising wetland areas to make best use of available land. Removal rates are limited by influent iron loadings, and area-adjusted iron-removal rates should be used with caution when assessing wetland performance. Sizing criteria for all types of treatment system might be refined if more detailed data become available.
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Barton, C. D. (1999). Renovation of a failed constructed wetland treating acid mine drainage. Environmental Geology, 39(1), 39–50.
Abstract: Acid mine drainage (AMD) from abandoned underground mines significantly impairs water quality in the Tones Branch watershed in McCreary Co., Kentucky, USA. A 1022-m(2) surface-flow wetland was constructed in 1989 to reduce the I AMD effects, however, the system failed after six months due to insufficient utilization of the treatment area, inadequate alkalinity production and metal overloading. In an attempt to improve treatment efficiencies, a renovation project was designed incorporating two anoxic limestone drains (ALDs) and a series of anaerobic subsurface drains that promote vertical now or mine water through a successive alkalinity producing system (SAPS) of limestone beds overlain by organic compost. Analytical results from the 19-month post-renovation period are very encouraging. Mean iron concentrations have decreased from 787 to 39 mg l(-1), pH increased from 3.38 to 6.46 and acidity has been reduced from 2244 to 199 mg l(-1) (CaCO3 equivalent). Mass removal rates averaged 98% for Al, 95% for Fe, 94% for acidity, 55% for sulfate and 49% for Mn during the study period. The results indicate increased alkalinity production from limestone dissolution and longer residence time have contributed to sufficient buffering and metal retention. The combination of ALDs and SAPS technologies used in the renovation and the sequence in which they were implemented within the wetland system proved to be an adequate and very promising design for the treatment of this and other sources of high metal load AMD.
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Bates, M. H., Veenstra, J. N., Barber, J., Bernard, R., Karleskint, J., Khan, P., et al. (1990). Physical-chemical treatment of acid-mine water from a superfund site. Journal of Environmental Systems, 19(3), 237–263.
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Bearcock, J. M. (2006). Accelerated precipitation of ochre for mine water remediation. Geochim. Cosmochim. Acta, 70(18), A42.
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Bechard, G. (1994). Use Of Cellulosic Substrates For The Microbial Treatment Of Acid-Mine Drainage. Journal of Environmental Quality, 23(1), 111–116.
Abstract: A mixed aerobic-anaerobic microbial treatment process was developed previously for acid mine drainage (AMD) using straw as a substrate. The process was effective only if AMD was supplemented with sucrose. The present study was conducted to determine which, if any, of three cellulosic materials could sustain the microbial treatment of AMD without the addition of a sucrose amendment and to determine the effect of the retention time on the performance of the reactors. The performance of small reactors that treated simulated AMD in the continuous mode was evaluated using alfalfa (Medicago sativa L.) hay, timothy (Phleum pratense L.) hay, and straw with a 5 d retention time. Parameters measured were pH, Fe, Al, sulfate, and ammonium. Timothy hay and straw sustained AMD mitigation for 3 wk, and thereafter all activity ceased. After the reactors ceased treating AMD, the mitigative activities were reinitiated by the addition of sucrose, but not by urea. Alfalfa sustained AMD mitigation for a longer time period than either straw or timothy. The effect of three retention times, 3.5, 7, and 35 d, was then investigated for reactors containing fresh alfalfa. Increasing the retention time resulted in better metal removal and a greater pH increase. With a 7-d retention time, 75 L of simulated AMD were neutralized from a pH of 3.5 to a pH value greater than 6.5. Reactors operating with a 3.5-d retention time treated only 58.3 L of simulated AMD before failing. Ammonium was detected in effluents of active reactors. The results of this study indicate that a low maintenance microbial treatment system can be developed with alfalfa as a substrate without the addition of a sucrose amendment.
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