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Wieder, R. K. (1989). A survey of constructed wetlands for acid coal mine drainage treatment in the Eastern United States. Wetlands, 9(2), 299–315.
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Carlson, L., & Kumpulainen, S. (2001). Retention of harmful elements by ochreous precipitates of iron. Tutkimusraportti Geologian Tutkimuskeskus, -(154), 30–33.
Abstract: The capability of soil fines to fix harmful elements, e.g. heavy metals and arsenic, depends on specific surface area and other characteristics, such as surface charge. In the pH-range typical of natural waters (pH 5,5-7,5), the surfaces of fine-grained silicate particles and manganese oxides are negatively charged; consequently cations, such as heavy metals, fix effectively to them. The iron oxide surfaces are usually positively charged and typically fix anions, such as sulphate and arsenate. Retention of anions is especially extensive to precipitates formed from acid mine drainage (pH 2,5-5,0). For example, precipitates found at Paroistenjarvi mine, Finland, contain more than 70 g/kg of arsenic (dry matter). Adsorbed anions, e.g. sulphate, enhance the capacity of precipitate to fix heavy metal cations in low-pH environments.
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Younger, P. L., Neal, C., House, W. A., Leeks, G. J. L., & Marker, A. H. (1997). The longevity of minewater pollution; a basis for decision-making U.K. fluxes to the North Sea; Land Ocean Interaction Study (LOIS); river basins research, the first two years. The Science of the Total Environment, 194-195, 457–466.
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Pettit, C. M., Scharer, J. M., Chambers, D. B., Halbert, B. E., Kirkaldy, J. L., & Bolduc, L. (1999). Neutral mine drainage. In D. Goldsack, N. Belzile, P. Yearwood, & G. J. Hall (Eds.), Sudbury '99; mining and the environment II; Conference proceedings. Sudbury: Sudbury Environmental.
Abstract: Acid mine drainage is recognized as a serious environmental issue at mine sites world wide. While sulphate and metal concentrations in acidic drainage can reach exceptionally high levels, these can also be elevated and of concern in neutral drainage from waste rock and tailings. “Neutral mine drainage” (NMD) has not yet received as widespread attention as acid mine drainage (AMD). The oxidation of sulphide minerals and the production of either acidic or neutral contaminated drainage is affected by many factors. This paper examines the specific factors that result in the production of “neutral mine drainage” from mine wastes. Several case studies are presented which involve predictive geochemical modelling to illustrate the possible time frame and magnitude of contaminated neutral drainage.
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Parker, G., Noller, B., & Waite, T. D. (1999). Assessment of the use of fast-weathering silicate minerals to buffer AMD in surface waters in tropical Australia. In D. E. Goldsack, N. Belzile, P. Yearwood, & G. J. Hall (Eds.), Sudbury '99; Mining and the environment II; Conference proceedings.
Abstract: Surface waters in the Pine Creek Geosyncline (located in Australia's “Top End”, defined as the area of Australia north of 15 degrees S) are characterized by their low carbonate buffering capacity. These waters are buffered by silicate weathering and hence are slightly acidic, ranging in pH from 4.0 to 6.0. The Pine Creek Geosyncline contains most of the Top Ends' economic mineral deposits and characteristically shows no correlation between carbonate minerals and sulfidic orebodies hosting gold deposits (unlike uranium deposits). Thus many gold mines do not have ready access to carbonate minerals for buffering acid mine drainage (AMD). It is possible that locally available fast-weathering silicate minerals may be used to buffer AMD seeps. The buffering intensity of silicate minerals exceeds that of carbonate minerals, but their slow dissolution kinetics has ensured that these materials have received little attention in treating AMD. In addition, carbonate mineral dissolution is retarded when contacted with intense AMD solutions due to the formation of surface coatings of iron minerals. The lower pH range of silicate mineral dissolution may prevent the formation of such coatings. The Pine Creek Geosyncline consists of a complex geochemistry, and a number of fast-weathering silicate minerals have been noted in various areas. The difficulty in assessing such minerals for use in buffering AMD is the lack of kinetic data available under conditions prevalent AMD (i.e., low pH solutions saturated with aluminium and silica). This study sets out to evaluate the applicability of using such minerals to treat AMD surface seeps.
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