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Hedin, R. S., Nairn, R. W., & Kleinmann, R. L. P. (1994). Passive Treatment of Coal Mine Drainage. Bureau of Mines Information Circular, Ic-9389, 1–35.
Abstract: Passive methods of treating mine water utilize chemical and biological processes that decrease metal concentrations and neutralize acidity. Compared to conventional chemical treatment, passive methods generally require more land area, but utilize less costly reagents and require less operational attention and maintenance. Currently, three types of passive technologies exist: aerobic wetlands, wetlands that contain an organic substrate, and anoxic limestone drains. Aerobic wetlands promote mixed oxidation and hydrolysis reactions, and are most effective when the raw mine water is net alkaline. Organic substrate wetlands promote anaerobic bacterial activity that results in the precipitation of metal sulfides and the generation of bicarbonate alkalinity. Anoxic limestone drains generate bicarbonate alkalinity and can be useful for the pretreatment of mine water before it flows into a wetland. Rates of metal and acidity removal for passive systems have been developed empirically. Aerobic wetlands remove Fe and Mn from alkaline water at rates of 10-20 g×m-2×d-1 and 0.5-1.0 g×m-2×d-1, respectively.
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Hedin, R. S., Watzlaf, G. R., & Nairn, R. W. (1994). Passive treatment of acid-mine drainage with limestone. J. Environ. Qual., 23(6), 1338–1345.
Abstract: The water treatment performances of two anoxic limestone drains (ALDs) were evaluated. Anoxic limestone drains are buried beds of Limestone that are intended to add bicarbonate alkalinity to flow-through acid mine drainage. Both ALDs received mine water contaminated with Fe2+ (216-279 mg L(-1)) and Mn (41-51 mg L(- 1)). Flow through the Howe Bridge ALD increased alkalinity by an average 128 mg L(-1) (CaCO3 equivalent) and Ca by 52 mg L(- 1), while concentrations of Fe, K, Mg, Mn, Na, and SO42- were unchanged. The Morrison ALD increased alkalinity by an average 248 mg L(-1) and Ca by 111 mg L(-1). Concentrations of K, Mg, Mn, and SO42- all decreased by an average 17%, an effect attributed to dilution with uncontaminated water. Iron, which decreased by 30%, was partially retained within the Morrison ALD. Calcite dissolution was enhanced at both sites by high P- CO2. Untreated mine waters at the Howe Bridge and Morrison sites had average calculated P-CO2 values of 6.39 kPa (10(- 1.20) atm) and 9.24 kPa (10(-1.04) atm), respectively. At both sites, concentrations of bicarbonate alkalinity stabilized at undersaturated values (SICalcite = 10(-1.2) at Howe Bridge and 10(-0.8) at Morrison) after flowing through approximately half of the limestone beds. Flow through the second half of each ALD had little additional effect on mine water chemistry. At the current rates of calcite solubilization, 17.9 kg d(-1) CaCO3 at Howe Bridge and 2.7 kg d(-1) CaCO3 at Morrison, the ALDs have theoretical effective lifetimes in excess of 20 yr. By significantly increasing alkalinity concentrations in the mine waters; both ALDs increased metal removal in downstream constructed wetlands.
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Nairn, R. W., Griffin, B. C., Strong, J. D., & Hatley, E. L. (2001). Remediation challenges and opportunities at the Tar Creek Superfund Site, Oklahoma. In R. Vincent, J. A. Burger, G. G. Marino, G. A. Olyphant, S. C. Wessman, R. G. Darmody, et al. (Eds.), Proceedings of the Annual National Meeting – American Society for Surface Mining and Reclamation, vol.18 (pp. 579–584).
Abstract: The Tar Creek Superfund Site is a portion of the abandoned lead and zinc mining area known as the Tri-State Mining District (OK, KS and MO) and includes over 100 square kilometers of disturbed land surface and contaminated water resources in extreme northeastern Oklahoma. Underground mining from the 1890s through the 1960s degraded over 1000 surface hectares, and left nearly 50 km of tunnels, 165 million tons of processed mine waste materials (chat), 300 hectares of tailings impoundments and over 2600 open shafts and boreholes. Approximately 94 million cubic meters of contaminated water currently exist in underground voids. In 1979, metal-rich waters began to discharge into surface waters from natural springs, bore holes and mine shafts. Six communities are located within the boundaries of the Superfund site. Approximately 70% of the site is Native American owned. Subsidence and surface collapse hazards are of significant concern. The Tar Creek site was listed on the National Priorities List (NPL) in 1983 and currently receives a Hazard Ranking System score of 58.15, making Tar Creek the nation's number one NPL site. A 1993 Indian Health Service study demonstrated that 35% of children had blood lead levels above thresholds dangerous to human health. Recent remediation efforts have focused on excavation and replacement of contaminated residential areas. In January 2000, Governor Frank Keating's Tar Creek Task Force was created to take a “vital leadership role in identifying solutions and resources available to address” the myriad environmental problems. The principle final recommendation was the creation of a massive wetland and wildlife refuge to ecologically address health, safety, environmental, and aesthetic concerns. Additional interim measures included continuing the Task Force and subcommittees; study of mine drainage discharge and chat quality; construction of pilot treatment wetlands; mine shaft plugging; investigations of bioaccumulation issues; establishment of an authority to market and export chat, a local steering committee, and a GIS committee; and development of effective federal, state, tribal, and local partnerships.
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Nairn, R. W., & Hedin, R. S. (1992). Designing wetlands for the treatment of polluted coal mine drainage. In M. C. Landin (Ed.), Wetlands; proceedings of the 13th annual conference; Society of Wetland Scientists (pp. 224–229).
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