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Gobla, M. J. (2002). A rapid response to cleanup – Gilt Edge Superfund Site, South Dakota. Tailings and Mine Waste '02, , 421–425.
Abstract: The Gilt Edge gold mine is an acid drainage site that has been put on an accelerated closure schedule. The mine ceased activities in 1999 when Dakota Mining Corporation declared bankruptcy forcing the State of South Dakota to immediatly assume water treatment operations. Evaluation of conceptual closure plan options and cost estimates led the State of South Dakota to a decision to seek Federal assistance. The site has quickly moved into reclamation mode for the principal contamination source, the Ruby waste-rock dump. Designs and specifications for capping the Ruby waste-rock dump were prepared while Superfund listing was pursued. In October of 2000, mobilization of the first reclamation contractor began and by December the site was added to the National Priorities List. Capping the waste-rock dump will address a major acid drainage source. Water treatment requirements are expected to decline as conventional methods such as diverting clean water, backfilling, grading, capping, limestone neutralization, and revegetation are implemented. Acid seepage from underground workings, steep highwalls, and some pit backfills will remain. Major field trials of emerging technologies are nearing completion and some are showing promising results. Carbon reduction in a pit lake, and pyrite microencapsulation on simulated waste dumps, are showing initial success. Their application may minimize or eliminate the need for long-term active water treatment which has been a long sought goal for major acid rock drainage sites.
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Fischer, R., Luckner, L., Peukert, D., Reißig, H., & Roßbach, B. (2002). Einsatz alkalischer Substanzen zur Verbesserung der Wasserqualität in Bergbaukippen. Use of alcine substances for the improvement of water quality in mining areas. Das Gas und Wasserfach. Ausgabe Wasser, Abwasser, 143(12), 891–898.
Abstract: Eisendisulfidminerale im Abraum von Braunkohlentagebauen können nach ihrer Verwitterung im wiederaufsteigenden Grundwasser erhebliche Güteverschlechterungen hinsichtlich pH-Wert, Schwermetall- und Sulfatgehalt verursachen. Diesen kann durch Zusätze alkalischer Substanzen zum Abraum wie Kalkstein, Dolomit und Kraftwerksasche bzw. Gemischen dieser Stoffe entgegengewirkt werden. Die Ergebnisse entsprechender Untersuchungen sowie die naturwissenschaftlichen Grundlagen der Eisendisulfidverwitterung werden im Beitrag dargestellt und ein Anwendungsbeispiel beschrieben. Grundlagen zur Berechnung der einzusetzenden Kalk- oder Aschemengen (bzw. Gemische der beiden Substanzen) sind die Bestimmung der oxidierbaren Sulfidminerale in den einzelnen geologischen Schichten sowie die Bestimmung der Pufferkapazität der Asche bzw. des Kalksteins. Besonders Vorteilhaft ist der Einsatz alkalischer Substanzen dort, wo durch vorhandene hohe Pyrit- und Markasitkonzentrationen mit einer erheblichen Versauerung des Grundwassers gerechnet und dadurch eine potentielle Beeinträchtigung von Grundwassernutzern erwartet werden muss. Solche Bedingungen sind im Rheinischen Braunkohlerevier, insbesondere im Umfeld des Tagebaus Garzweiler II (RWE Rheinbraun AG) gegeben. Derzeit werden im Tagebau Garzweiler bereits 40000 t Kalkstein dem Abraum beigemischt. Auch für das Lausitzer Braunkohlenrevier könnte ein Einsatz alkalischer Substanzen in Betracht gezogen werden.
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Dennison, F. E. (2002). Constructed wetlands for the treatment of British mine drainage waters : a biogeochemical approach. Ph.D. thesis, University of Wales,, Bangor.
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Demin, O. A., Dudeney, A. W. L., & Tarasova, I. I. (2002). Remediation of Ammonia-rich Minewater in Constructed Wetlands. Environ. Technol., 23(5), 497–514.
Abstract: A three-year study of ammonia removal from minewater was carried out employing constructed wetland systems (surface flow wetland and subsurface flow wetland cells) at the former Woolley Mine in West Yorkshire, UK The 1.4 Ha surface flow wetland (constructed in 1995) reduced the ammonia concentration from 3.5 – 4.5 mg l(-1) to < 2 3 mg V during the first half of the study and to essentially zero in the last year (2000 – 2001). About 25 % of contained ammonia was converted to nitrate, about 10 % was consumed by the plants and up to 30 % was converted to nitrogen gas. This maturation effect was attributed to increased depth of sludge from sedimentation of ochre, providing increased surface area for immobilisation of ammonia oxidising bacteria. The surface flow wetland finally removed 23 g m(-2) day(-1) ammonia in comparison with 3.8 g m(-2) day' for the subsurface flow (pea gravel) wetland cells, constructed for the present work and dosed with ammonium salts. Removal of ammonia by both systems was consistent with well-established mechanisms of nitrification and denitrification. It was also consistent with ammonia removal in wastewater wetland systems, although the greater aeration in the minewater systems obviated the need for special aeration cycles. The general role of wetland plants in such aerated conditions was attributed to maintaining hydraulic conditions (such as hydraulic efficiency and hydraulic resistance of substratum in subsurface flow systems) in the wetlands and providing a suspended solids filter for minewater.
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Cravotta, C. A., III, Watzlaf, G. R., Naftz, D. L., Morrison, S. J., Fuller, C. C., & Davis, J. A. (2002). Design and performance of limestone drains to increase pH and remove metals from acidic mine drainage Handbook of groundwater remediation using permeable reactive barriers; applications to radionuclides, trace metals, and nutrients.. Amsterdam: Academic Press.
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