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Bamforth, S. M. (2006). Manganese removal from mine waters – investigating the occurrence and importance of manganese carbonates. Appl. Geochem., 21(8), 1274–1287.
Abstract: Manganese is a common contaminant of mine water and other waste waters. Due to its high solubility over a wide pH range, it is notoriously difficult to remove from contaminated waters. Previous systems that effectively remove Mn from mine waters have involved oxidising the soluble Mn(II) species at an elevated pH using substrates such as limestone and dolomites. However it is currently unclear what effect the substrate type has upon abiotic Mn removal compared to biotic removal by in situ micro-organisms (biofilms). In order to investigate the relationship between substrate type, Mn precipitation and the biofilm community, net-alkaline Mn-contaminated mine water was treated in reactors containing one of the pure materials: dolomite, limestone, magnesite and quartzite. Mine water chemistry and Mn removal rates were monitored over a 3-month period in continuous-flow reactors. For all substrates except quartzite, Mn was removed from the mine water during this period, and Mn minerals precipitated in all cases. In addition, the plastic from which the reactor was made played a role in Mn removal. Manganese oxyhydroxides were formed in all the reactors; however, Mn carbonates (specifically kutnahorite) were only identified in the reactors containing quartzite and on the reactor plastic. Magnesium-rich calcites were identified in the dolomite and magnesite reactors, suggesting that the Mg from the substrate minerals may have inhibited Mn carbonate formation. Biofilm community development and composition on all the substrates was also monitored over the 3-month period using denaturing gradient gel electrophoresis (DGGE). The DGGE profiles in all reactors showed no change with time and no difference between substrate types, suggesting that any microbiological effects are independent of mineral substrate. The identification of Mn carbonates in these systems has important implications for the design of Mn treatment systems in that the provision of a carbonate-rich substrate may not be necessary for successful Mn precipitation. (c) 2006 Elsevier Ltd. All rights reserved.
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Banks, D., Younger, P. L., Arnesen, R. - T., Iversen, E. R., & Banks, S. B. (1997). Mine-water chemistry: The good, the bad and the ugly. Environ. Geol., 32(3), 157–174.
Abstract: Contaminative mine drainage waters have become one of the major hydrogeological and geochemical problems arising from mankind's intrusion into the geosphere. Mine drainage waters in Scandinavia and the United Kingdom are of three main types: (1) saline formation waters; (2) acidic, heavy-metal-containing, sulphate waters derived from pyrite oxidation, and (3) alkaline, hydrogen-sulphide-containing, heavy-metal-poor waters resulting from buffering reactions and/or sulphate reduction. Mine waters are not merely to be perceived as problems, they can be regarded as industrial or drinking water sources and have been used for sewage treatment, tanning and industrial metals extraction. Mine-water problems may be addressed by isolating the contaminant source, by suppressing the reactions releasing contaminants, or by active or passive water treatment. Innovative treatment techniques such as galvanic suppression, application of bactericides, neutralising or reducing agents (pulverised fly ash-based grouts, cattle manure, whey, brewers' yeast) require further research.
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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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Banks, S. B. (2003). The Coal Authority Minewater Treatment Programme: An update on the performance of operational schemes. Land Contam. Reclam., 11(2), 161–164.
Abstract: The performance of mine water treatment schemes, operated under the Coal Authority's national Minewater Treatment Programme, is summarised. Most schemes for which data are available perform successfully and remove over 90% iron. Mean area-adjusted iron removal rates for reedbed components of treatment schemes, range from 1.5 to 5.5 g Fe/m2, with percentage iron removal rates ranging from 68% to 99%. In the majority of cases, calculated area-adjusted removal rates are limited by influent iron loadings, and the empirical sizing criterion for aerobic wetlands, based on American removal rates of 10 g Fe/m2day, remains a valuable tool in the initial stages of treatment system design and estimation of land area requirements. Where a number of schemes have required modification after becoming operational, due consideration must always be given to the potential for dramatic increases in influent iron loadings, and to how the balance between performance efficiency and aesthetic appearance can best be achieved. Continual review and feedback on the performance of treatment systems, and the problems encountered during design implementation, will enhance the efficiency and effectiveness of the Minewater Treatment Programme within the UK.
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Banks, S. B., & Banks, D. (2001). Abandoned mines drainage; impact assessment and mitigation of discharges from coal mines in the UK. In R. N. Yong, & H. R. Thomas (Eds.), Geoenvironmental engineering Engineering Geology (pp. 31–37). 60.
Abstract: The UK has a legacy of pollution caused by discharges from abandoned coal mines, with the potential for further pollution by new discharges as groundwaters continue to rebound to their natural levels. In 1995, the Coal Authority initiated a scoping study of 30 gravity discharges from abandoned coal mines in England and Scotland. Mining information, geological information and water quality data were collated and interpreted in order to allow a preliminary assessment of the source and nature of each of the discharges. An assessment of the potential for remediation was made on the basis of the feasibility and relative costs of alternative remediation measures. Environmental impacts of the discharges and of the proposed remediation schemes were also assessed. The results, together with previous Coal Authority studies of discharges in Wales, were used by the Coal Authority, in collaboration with the former National Rivers Authority and the former Forth and Clyde River Purification Boards, to rank discharge sites in order of priority for remediation.
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