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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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Sottnik, P., & Sucha, V. (2001). Moznosti upravy kysleho banskeho vytoku loziska Banska Stiavnica-Sobov. Remediation of acid mine drainage from Sobov Mine, Banska Stiavnica. Mineralia Slovaca, 33(1), 53–60.
Abstract: A waste dump formed during the exploitation of quartzite deposit in Sobov mine (Slovakia) produces large quantity of acid mine drainage (AMD) which is mainly a product of pyrite oxidation. Sulphuric acid--the most aggressive oxidation product--attacks gangue minerals, mainly clays, as well. This process lead to a sharp decrease of the pH values (2-2.5) and increase of Fe, Al and SO (super 2-) (sub 4) contents (TDS = 20-30 mg/1). Passive treatment system was designed to remediate AMD. Chemical redox reactions along with microbial activity cause a precipitation of mobile contamination into a more stable forms. The sulphides are formed in the anaerobic cell, under reducing conditions. Fe-, Al- oxyhydroxides are precipitated in the aerobic part of the system. Precipitation decreases the Fe and Al contents along with immobilization of some heavy metal closely related to oxyhydroxides. Besides oxidation, the wetland vegetation is an active part of on aerobic cell. The system has been working effectively since September 1999. The pH values of outflowing water are apparently higher (6.2-6.8) and contents of dissolved elements (Fe from 2.260 to 4.1; Al from 900 to 0.18; Mn from 51 to 23; Cu from 4.95 to 0.03 mg/l) is significantly lowers.
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Chung, I. J. (2001). Immobilization of arsenic in tailing by using iron and hydrogen peroxide. Environ. Technol., 22(7), 831–835.
Abstract: Under environmental conditions, arsenic (As) reveals anionic behavior and is converted into various forms in accordance with the Eh/pH condition. This causes the difficulty of treating As with other heavy metals in tailing. This study was carried out to develop the immobilization method of arsenic in tailing as ferric arsenate (FeAsO4) using hydrogen peroxide. According to experimental results, the extracted concentrations of arsenic and iron (Fe) from tailing were reduced up to 84% and 93%, respectively. In the experiment using pure Pyrite (FeS2) and As solution, As concentration decreased with an increase of hydrogen peroxide dosage. The experimental results of re-extraction showed that only 10% of As and 20% of Fe were extracted in the case of using hydrogen peroxide. As a result, the long-term stability of this method was clarified.
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Gatzweiler, R. (2001). Cover design for radioactive and AMD-producing mine waste in the Ronneburg area, Eastern Thuringia. Waste Management, 21(2), 175–184.
Abstract: At the former uranium mining site of Ronneburg, large scale underground and open pit mining for nearly 40 years resulted in a production of about 113 000 tonnes of uranium and about 200 million cubic metres of mine waste. In their present state, these materials cause risks to human health and strong environmental impacts and therefore demand remedial action. The remediation options available are relocation of mine spoil into the open pit and on site remediation by landscaping/contouring, placement of a cover and revegetation. A suitable vegetated cover system combined with a surface water drainage system provides long-term stability against erosion and reduces acid generation thereby meeting the main remediation objectives which are long-term reduction of radiological exposure and contaminant emissions and recultivation. The design of the cover system includes the evaluation of geotechnical, radiological, hydrological, geochemical and ecological criteria and models. The optimized overall model for the cover system has to comply with general conditions as, e.g. economic efficiency, public acceptance and sustainability. Most critical elements for the long-term performance of the cover system designed for the Beerwalde dump are the barrier system and its long-term integrity and a largely self-sustainable vegetation. (C) 2001 Elsevier Science Ltd. All rights reserved.
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Goulet, R. R. (2001). The evaluation of metal retention by a constructed wetland using the pulmonate gastropod Helisoma trivolvis (Say). Archives of Environmental Contamination and Toxicology, 40(3), 303–310.
Abstract: Constructed wetlands are built because they can act as sinks fur many pollutants, thereby protecting the water quality of downstream ecosystems. The treatment performance is generally assessed using mass balance calculations. Along with the mass balance approach, we compared the metal content of populations of a common pond snail (Helisoma trivolvis Say) collected upstream and downstream of a 3-year-old constructed wetland. Snails were collected in early May, June, and August 1998. At the same time, water samples for particulate and dissolved metals were taken every 3 days for the duration of the experiment. Overall, the wetland retained most dissolved metals, including Fe, Mn, Cu, Zn, Ni, and Pb, but released dissolved As. However, the wetland released particulate Fe and Mn. With the exception of Zn, the metal concentrations of the downstream snails were on average higher than those measured in the upstream population. The higher metal content of downstream snails was likely related to the significant export of particulate metals by the wetland, despite the overall retention of dissolved metals. This study points to the need for biological as well as chemical monitoring to determine the treatment efficiency and toxicological risk associated with constructed wetlands.
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