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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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Gerth, A., & Kießig, G. (2001). (A. Leeson, Ed.). Phytoremediation, wetlands and sediments. (6)5: Battelle Press.
Abstract: Treatment of radioactively-contaminated and metal-laden mine waters and of seepage fiom tailings ponds and waste rock piles is among the key issues facing WISMUT GmbH in their task to remediate the legacy of uranium mining and processing in the Free States of saxony and rhuringia, Federal Republic of Germany. Generally, contaminant loads of feed waters wn aimnisn over time. At a certain level of costs for the removal of one contaminant unit, continued operation of conventional water treatment plants can hardly be justified any longer. As treatment is still required for water protection, there is an urgent need for-the development and implementation of more cost efficient technologies. WISMUT GmbH and BioPlanta GmbH have studied the suitability of helophye species for contaminant removal from mine waters. In a fust step, original waters were used for an in vitro bioassay. The test results allowed for the determination of the effects of biotic and abiotic factors on helophy'tes'tolerancer ange, growth, and uptake capability of radionuclides and metals. Test series were carried out using Phiagmites australis, Carex disticha, Typha latifolia, and Juncus effusus. Relevant cont-aminant components of the mine waters under investigation included uraniunl iron, arsenic, manganese, nickel, and copper. Investigations led to a number of recommendations conceming plant selection for specific water treatment needs. In a second step, based on these results, a constructed wetland was built in l99g as a pilot plant for the treatment of flood waters liom the pöhla-Tellerhäuser mine and went on-line. Relevant constituents of the neutral flood waters include radium, iron, and arsenic. This wetland specifically uses both physico-chemical and microbiological processes as well as contaminant accumulation by helophytes to achieve the treatment objectives. with the pilot plant in operation for three years now, average removal rates achieved are 95 Yo for kon, 86 yo for arsenic, and 75 % for raäium. WISMUT GmbH intends to put a number of other projects of passive/biological mine water treatment into operation before the end of 2001_
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Goulet, R. R. (2001). Changes in dissolved and total Fe and Mn in a young constructed wetland: Implications for retention performance. Ecological Engineering, 17(4), 373–384.
Abstract: Surface-flow wetlands are generally considered sinks for Fe and Mn but they may also export and affect the partitioning of these metals. This study was undertaken to evaluate the effect of a young constructed wetland on the retention and transformation of both dissolved and particulate Fe and Mn. Duplicate water samples were collected every three days at the inlet and outlet structures of the Monahan Wetland, Kanata, Ontario, from spring of 1997 to 1999. While on a yearly basis the wetland showed significant retention of che dissolved phase, the retention of total Fe and Mn was poor. There were strong seasonal differences in retention and, during the winter, the wetland was a source. The wetland transformed dissolved into particulate Fe and Mn from spring to fall whereas during the winter, dissolved Fe and Mn were released. Changes in pH, alkalinity and temperature could explain 11% and 40% of the outlet variation in the ratio of dissolved to total Fe and Mn respectively. Furthermore, from spring to late summer, planktonic algal biomass was negatively related to the ratio of dissolved to total Fe and Mn implying a role in Fe and Mn transformations in young wetlands where emergent and submerged vegetation have yet to dominate the system. (C) 2001 Elsevier Science B.V. 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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Govind, R. (2001). Treatment of acid mine drainage using membrane bioreactors. Bioremediation of Inorganic Compounds, 6(9), 1–8.
Abstract: Acid mine drainage is a severe water pollution problem attributed to past mining activities. The exposure of the post-mining mineral residuals to water and air results in a series of chemical and biological oxidation reactions, that produce an effluent which is highly acidic and contains high concentrations of various metal sulfates. Several treatment techniques utilizing sulfate reducing bacteria have been proposed in the past; however few of them have been practically applied to treat acid mine drainage. This research deals with membrane reactor studies to treat the acid mine drainage water from Berkeley Pit in Butte, Montana using hydrogen-consuming sulfate reducing bacteria. Eventually, the membrane reactor system can be applied towards the treatment of acid mine drainage to produce usable water.
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