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Author Arango, I. openurl 
  Title Evaluation of the beneficial effects of the acidophilic alga Euglena mutabilis on acid mine drainage systems Type Book Whole
  Year 2002 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords (up) acid mine drainage atmospheric precipitation benthic taxa bioremediation dissolved materials dissolved oxygen electron microscopy data Euglena mutabilis Green Valley Mine ICP mass spectra Indiana iron mass spectra metals microorganisms mines oxygen pH photochemistry photosynthesis pollution rain remediation sediments soils spectra temperature United States Vigo County Indiana water 22, Environmental geology  
  Abstract Euglena mutabilis is an acidophilic, photosynthetic protozoan that forms benthic mats in acid mine drainage (AMD) channels. At the Green Valley mine, western Indiana, E. mutabilis resides in AMD measuring <4.2 pH, with high concentrations of dissolved constituents (up to 22.67 g/l). One of the main factors influencing E. mutabilis distribution is water temperature. The microbe forms thick (>1 mm), extensive mats during spring and fall, when water temperature is between 13 and 28 degrees C. During winter and summer, when temperatures are outside this range, benthic communities have a very patchy distribution and are restricted to areas protected from extreme temperature changes. E. mutabilis also responds to rapid increases in pH, which are associated with rainfall events. During these events pH can increase above 4.0, causing precipitation of Fe and Al oxy-hydroxides that cover the mats. The microbe responds by moving through the precipitates, due to phototaxis, and reestablishing the community at the sediment-water interface within 12 hours. The biological activities of E. mutabilis may have a beneficial effect on AMD systems by removing iron from effluent via oxygenic photosynthesis, and/or by internal sequestration. Photosynthesis by E. mutabilis contributes elevated concentrations of dissolved oxygen (DO), up to 17.25 mg/l in the field and up to 11.83 mg/l in the laboratory, driving oxidation and precipitation of reduced metal species, especially Fe (II), which are dissolved in the effluent. In addition, preliminary electro-microscopic and staining analyses of the reddish intracellular granules in E. mutabilis indicate that the granules contain iron, suggesting that E. mutabilis sequesters iron from AMD. Inductive coupled plasma analysis of iron concentration in AMD with and without E. mutabilis also shows that E. mutabilis accelerates the rate of Fe removal from the media. Whether iron removal is accelerated by internal sequestration of iron and/or by precipitation via oxygenic photosynthesis has yet to be determined. These biological activities may play an important role in the natural remediation of AMD systems.  
  Address  
  Corporate Author Thesis Ph.D. thesis  
  Publisher Indiana State University, Place of Publication Terre Haute Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Evaluation of the beneficial effects of the acidophilic alga Euglena mutabilis on acid mine drainage systems; GeoRef; English; References: 39; illus. incl. 3 tables Approved no  
  Call Number CBU @ c.wolke @ 16491 Serial 476  
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Author Herbert, R.B., Jr.; Benner, S.G.; Blowes, D.W. url  isbn
openurl 
  Title Reactive barrier treatment of groundwater contaminated by acid mine drainage; sulphur accumulation and sulphide formation Type Book Chapter
  Year 1998 Publication Groundwater Quality: Remediation and Protection Abbreviated Journal  
  Volume Issue Pages 451-457  
  Keywords (up) acid mine drainage Canada chemical analysis contaminant plumes Eastern Canada ground water hydraulic conductivity hydrolysis Nickel Rim Mine Ontario pH pollution porosity pyrrhotite remediation sample preparation Sudbury Basin sulfides sulfur tailings water pollution 22, Environmental geology  
  Abstract A permeable reactive barrier was installed in August 1995 at the Nickel Rim Mine near Sudbury, Ontario, Canada, for the passive remediation of groundwater contaminated with acid mine drainage. The reactive component of the barrier consists of a mixture of municipal and leaf compost and wood chips: the organic material promotes bacterially-mediated sulphate reduction. Hydrogen sulphide, a product of sulphate reduction, may then complex with aqueous ferrous iron and precipitate as iron sulphide. This study presents the solid phase sulphur chemistry of the reactive wall after two years of operation, and discusses the formation and accumulation of iron sulphide minerals in the reactive material. The results from the solid-phase chemical analysis of core samples indicate that there is an accumulation of reduced inorganic sulphur in the reactive wall, with levels reaching 190 mu mol g (super -1) (dry weight) by July 1997.  
  Address  
  Corporate Author Thesis  
  Publisher IAHS-AISH Publication, vol.250 Place of Publication Editor Herbert, M.; Kovar, K.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 1901502554 Medium  
  Area Expedition Conference  
  Notes Reactive barrier treatment of groundwater contaminated by acid mine drainage; sulphur accumulation and sulphide formation; GeoRef; English; 1999-065115; GQ 98 conference, Tubingen, Federal Republic of Germany, Sept. 21-24, 1998 References: 15; illus. Approved no  
  Call Number CBU @ c.wolke @ 16621 Serial 65  
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Author Benzaazoua, M.; Bussiere, B. isbn  openurl
  Title Desulphurization of tailings with low neutralizing potential; kinetic study and flotation modeling Type Book Chapter
  Year 1999 Publication Sudbury '99; Mining and the environment II; conference proceedings Abbreviated Journal  
  Volume Issue Pages  
  Keywords (up) acid mine drainage chemical properties chemical reactions environmental analysis environmental effects experimental studies flotation geochemistry kinetics laboratory studies mathematical models neutralization pH pollution sulfur tailings 22 Environmental geology 02A General geochemistry  
  Abstract Environmental desulphurization is an attractive alternative for acid generating tailings management as demonstrated during the last few years. In fact, such process placed at the end of the primary treatment circuit allows to reduce greatly the amount of problematic tailings by concentrating the sulphidic fraction. Moreover, the desulphurized tailings (non-acid generating) have the geotechnical and environmental properties for being used as fine material in a cover with capillary barrier effects. To produce desulphurized tailings, non selective froth flotation is the most adapted method as shown in many previous works. Desulphurization level is fixed by tailings sulphur content (or sulphide content) and neutralization potential NP. The final residue should have enough NP to compensate for his acid generating potential AP. In this paper, the authors present the results of laboratory tests conducted in Denver cells for studying the sulphide flotation kinetics of four mine tailings which are characterized by a weak neutralization potential (under 37 kg CaCO (sub 3) /t). Tailings 1, 2, 3 and 4 contain respectively 5.27, 10, 4.25 and 16.9 sulphur Wt. %. Tailings 1 and 2 are cyanide free and are well floated at pH around 11 by using amyl xanthate as collector. Collector dosage was optimized for these tailings and the results show that Tailing 2 need more collector. However, Tailings 3 and 4, which come from a gold cyanidation process, could not provide good sulphide recovery with xanthate collector because of the pyrite depression. To overcome this problem, amine acetate was used successfully but induces important entrainment. The consumption of this collector was also optimized. The results of kinetic tests and collector dosage were combined and modeled to establish relationships which allow to estimate the desulphurization performances.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor Goldsack, D.; Belzile, N.; Yearwood, P.; Hall, G.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 0886670470 Medium  
  Area Expedition Conference  
  Notes Desulphurization of tailings with low neutralizing potential; kinetic study and flotation modeling; GeoRef; English; 2002-060841; Sudbury '99; Mining and the environment II--Sudbury '99; L'exploitation miniere et l'environnement, Sudbury, ON, Canada, Sept. 13-17, 1999 References: 26; illus. incl. 5 tables Approved no  
  Call Number CBU @ c.wolke @ 16572 Serial 452  
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Author Aube, B.C.; Zinck, J.M. openurl 
  Title Comparison of AMD treatment processes and their impact on sludge characteristics Type Journal Article
  Year 1999 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords (up) acid mine drainage cost decontamination density discharge geochemistry hydrochemistry leaching lime metals mine dewatering neutralization pH pollution remediation sludge stability tailings toxicity viscosity waste disposal water treatment 22, Environmental geology  
  Abstract Lime neutralisation for the treatment of acid mine drainage is one of the oldest water pollution control techniques practised by the mineral industry. Several advances have been made in the process in the last thirty years, particularly with respect to discharge concentrations and sludge density. However, the impact of different treatment processes on metal leachability and sludge handling properties has not been investigated. A study of treatment sludges sampled from various water treatment plants has shown that substantial differences can be related to the treatment process and raw water composition. This study suggests that sludge densities, excess alkalinity, long-term compaction properties, metal leachability, crystallinity and cost efficiency can be affected by the neutralisation process and specific process parameters. The study also showed that the sludge density and dewatering ability is not positively correlated with particle size as previously suggested in numerous studies. The treatment process comparisons include sludge samples from basic lime treatment, the conventional High Density Sludge (HDS) Process, and the Geco HDS Process.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Sudbury Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Mining and the Environment II Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes 2002-060865; Sudbury '99; Mining and the environment II--Sudbury '99; L'exploitation miniere et l'environnement, Sudbury, ON, Canada, Sept. 13-17, 1999 References: 10; illus. incl. 6 tables; GeoRef; English Approved no  
  Call Number CBU @ c.wolke @ 16574 Serial 473  
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Author Pettit, C.M.; Scharer, J.M.; Chambers, D.B.; Halbert, B.E.; Kirkaldy, J.L.; Bolduc, L. isbn  openurl
  Title Neutral mine drainage Type Book Chapter
  Year 1999 Publication Sudbury '99; mining and the environment II; Conference proceedings Abbreviated Journal  
  Volume Issue Pages  
  Keywords (up) acid mine drainage drainage geochemistry mining mining geology models neutral mine drainage pH pollution remediation technology water management water quality water resources 22, Environmental geology  
  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.  
  Address  
  Corporate Author Thesis  
  Publisher Sudbury Environmental Place of Publication Sudbury Editor Goldsack, D.; Belzile, N.; Yearwood, P.; Hall, G.J.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 0886670470 Medium  
  Area Expedition Conference  
  Notes Neutral mine drainage; GeoRef; English; 2000-043769; Sudbury '99; Mining and the environment II--Sudbury '99; L'exploitation miniere et l'environnement II, Sudbury, ON, Canada, Sept. 13-17, 1999 References: 12; illus. incl. 3 tables Approved no  
  Call Number CBU @ c.wolke @ 16589 Serial 270  
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