WorldWideScience

Sample records for acid mine drainage

  1. Acid mine drainage research in Canada

    Acidic drainage resulting from base metal, precious metal, and uranium mining is the largest single environmental problems facing the Canadian mining industry today. Technologies to prevent acidic drainage from occurring in waste rock piles and tailings sites, and on the walls of open pits and underground mines, need to be developed and demonstrated. There are two grounds in Canada which have accepted this challenge: the national Mine Environment Neutral Drainage (MEND) program and the British Columbia Acid Mine Drainage (BC AMD) Task Force. This paper summarizes the activities of these two organizations

  2. FISH HABITATS IMPACTED BY ACIDIC MINE DRAINAGE

    This data set represents in-stream fish spawning and hatching areas that have been impacted by elevated acid content waters discharging from areas near mining activities. It is based on an EPA fisheries survey completed in 1995. Acid Mine Drainage, or AMD, occurs when water co...

  3. GROUNDWATER IMPACTED BY ACID MINE DRAINAGE

    The generation and release of acidic, metal-rich water from mine wastes continues to be an intractable environmental problem. Although the effects of acid mine drainage (AMD) are most evident in surface waters, there is an obvious need for developing cost-effective approaches fo...

  4. Biological alkalinity generation in acid mine drainage

    Ecological Engineering and Biological Polishing technologies are a decommissioning approach to inactive coal, uranium and base metal mining operations. To improve acid mine drainage water, some fundamental aspects of wetland ecology and sediment microbiology are combined. The combination provides conditions which allow biomineralization of the contaminants. The authors report here the first records of microbial alkalinity generation in acid mine drainage, through the utilization of the ARUM (Acid Reduction Using Microbiology) process. Increases in pH are brought about by alkalinity-generating microbes such as sulfate reducers, iron reducers, methanogens, or denitrifiers. The ARUM process has been successful in increasing pH from 2.5 to 7.0 in laboratory-scale flow-through reactors operated continuously for more than 120 days. Ni was also reduced from 13 mg/l to < 0.01 mg/l. Batch ARUMators in the field have also performed well. Design parameters are being developed for low flow rates of 5 l/min in a pilot-scale system receiving seepage from mine tailings

  5. Evolution of Acid Mine Drainage Formation in Sulphidic Mine Tailings

    Bernhard Dold

    2014-01-01

    Sulphidic mine tailings are among the largest mining wastes on Earth and are prone to produce acid mine drainage (AMD). The formation of AMD is a sequence of complex biogeochemical and mineral dissolution processes. It can be classified in three main steps occurring from the operational phase of a tailings impoundment until the final appearance of AMD after operations ceased: (1) During the operational phase of a tailings impoundment the pH-Eh regime is normally alkaline to neutral and reduci...

  6. Chemical abatement of acid mine drainage formation

    Steven, J.

    1987-01-01

    Chemical and thermodynamic data were used to develop a unified model of hydroxo-, sulfato-, and bisulfato-iron complexes and their stability constants in iron-sulfate solutions. Free energy of formation for each ligand series species was hypothesized to be linear in ligand number because of supporting evidence from the literature. Laboratory tests on the inhibition of acid mine drainage bacteria were conducted. Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds. Low-pH cultures of Thiobacillus thioxidans significantly increased zinc sulfide dissolution rates relative to sterile controls. Sodium lauryl sulfate, benzoic acid, and sorbic acid at concentrations of 10, 25, and 50 mg/liter, respectively, in identical low-pH, batch cultures of Thiobacillus thiooxidans, were sufficient for complete inhibition of bacterial zinc sulfide dissolution. Pilot-scale experiments on the abatement of acid mine drainage formation in both fresh and weathered pyritic coal refuse were also conducted. At doses of 0.5 g/kg and 5.0 g/kg in fresh and weathered refuse, respectively, sodium benzoate, potassium sorbate, and most significantly, sodium lauryl surface, reduced the rate of iron, sulfate, and acidity production in water-leached barrels of coal refuse material.

  7. Bioreactor for acid mine drainage control

    Zaluski, Marek H.; Manchester, Kenneth R.

    2001-01-01

    A bioreactor for reacting an aqueous heavy metal and sulfate containing mine drainage solution with sulfate reducing bacteria to produce heavy metal sulfides and reduce the sulfuric acid content of the solution. The reactor is an elongated, horizontal trough defining an inlet section and a reaction section. An inlet manifold adjacent the inlet section distributes aqueous mine drainage solution into the inlet section for flow through the inlet section and reaction section. A sulfate reducing bacteria and bacteria nutrient composition in the inlet section provides sulfate reducing bacteria that with the sulfuric acid and heavy metals in the solution to form solid metal sulfides. The sulfate reducing bacteria and bacteria nutrient composition is retained in the cells of a honeycomb structure formed of cellular honeycomb panels mounted in the reactor inlet section. The honeycomb panels extend upwardly in the inlet section at an acute angle with respect to the horizontal. The cells defined in each panel are thereby offset with respect to the honeycomb cells in each adjacent panel in order to define a tortuous path for the flow of the aqueous solution.

  8. Remediation of Acid Mine Drainage with Sulfate Reducing Bacteria

    Hauri, James F.; Schaider, Laurel A.

    2009-01-01

    Sulfate reducing bacteria have been shown to be effective at treating acid mine drainage through sulfide production and subsequent precipitation of metal sulfides. In this laboratory experiment for undergraduate environmental chemistry courses, students design and implement a set of bioreactors to remediate acid mine drainage and explain observed…

  9. Copper isotope fractionation in acid mine drainage

    Kimball, B.E.; Mathur, R.; Dohnalkova, A.C.; Wall, A.J.; Runkel, R.L.; Brantley, S.L.

    2009-01-01

    We measured the Cu isotopic composition of primary minerals and stream water affected by acid mine drainage in a mineralized watershed (Colorado, USA). The ??65Cu values (based on 65Cu/63Cu) of enargite (??65Cu = -0.01 ?? 0.10???; 2??) and chalcopyrite (??65Cu = 0.16 ?? 0.10???) are within the range of reported values for terrestrial primary Cu sulfides (-1??? fractionation (??aq-min = ??65Cuaq - ??65Cumin, where the latter is measured on mineral samples from the field system), equals 1.43 ?? 0.14??? and 1.60 ?? 0.14??? for chalcopyrite and enargite, respectively. To interpret this field survey, we leached chalcopyrite and enargite in batch experiments and found that, as in the field, the leachate is enriched in 65Cu relative to chalcopyrite (1.37 ?? 0.14???) and enargite (0.98 ?? 0.14???) when microorganisms are absent. Leaching of minerals in the presence of Acidithiobacillus ferrooxidans results in smaller average fractionation in the opposite direction for chalcopyrite (??aq-mino = - 0.57 ?? 0.14 ???, where mino refers to the starting mineral) and no apparent fractionation for enargite (??aq-mino = 0.14 ?? 0.14 ???). Abiotic fractionation is attributed to preferential oxidation of 65Cu+ at the interface of the isotopically homogeneous mineral and the surface oxidized layer, followed by solubilization. When microorganisms are present, the abiotic fractionation is most likely not seen due to preferential association of 65Cuaq with A. ferrooxidans cells and related precipitates. In the biotic experiments, Cu was observed under TEM to occur in precipitates around bacteria and in intracellular polyphosphate granules. Thus, the values of ??65Cu in the field and laboratory systems are presumably determined by the balance of Cu released abiotically and Cu that interacts with cells and related precipitates. Such isotopic signatures resulting from Cu sulfide dissolution should be useful for acid mine drainage remediation and ore prospecting purposes. ?? 2008 Elsevier Ltd.

  10. Acid drainage (AD) in nature and environmental impact of acid mine drainage (AMD) in Southern Tuscany

    Acid drainage (AD) is a natural process occurring locally at the Earth's surface. It consists in a substantial increase of acidity of surface waters as a result of chemical reactions occurring in the atmosphere (i.e. acid rain) or involving reactive phases (i.e. pyrite) present in the percolated medium. Acidic surface waters (usually pH < 4) can be produced by oxidation of sulphides (mainly pyrite and other iron sulphides) exposed to atmospheric oxygen, while human activities, such as mining, can greatly enhance this process. Acid drainage promoted by mining activities is called acid mine drainage (AMD) and is a primary source of environmental pollution and a world-wide problem in both active and abandoned mining areas. In fact, exposure of iron sulphides to oxidising conditions produces strongly acidic drainage waters rich in sulphate and a variety of heavy elements (i.e. As, Cd, Pb, Sb). Several occurrences of active acid mine drainage have been found in the Metalliferous Hills (southern Tuscany). The most important AMD phenomena were observed in the Fenice Capanne and Niccioleta mining areas

  11. Origin of acid mine drainage in Enugu

    Mine flooding is a serious problem in the Enugu Coal Mines and has led to the abandonment of two of the four mines. About 1800 m3 of water is pumped out daily from the mines into the nearby streams. The source of this enormous volume of water has been established based on the hydrodynamics and hydrology of the area. Two prolific aquifers - an unconfined and a confined system - overlie the mines, but the mine water is derived principally from the unconfined aquifer. The pathway of flow is, provided by the numerous fractures connecting the two aquifers and the mine tunnel. The major hydrochemical activity resulting in pollution of the mine water occurs within the sumps in the floor of the longwalls. These sumps act as oxidation chambers where groundwater from the fractures mixes and subsequently reacts with sulfur-rich solutes released by coal mining. Contrary to general belief, the mine drainage has not seriously degraded the chemistry of receiving streams. The pH and electric conductivity, representing, the dissolved ions, were increased less than 10% of the values in the unaffected region

  12. Acid mine drainage: mining and water pollution issues in British Columbia

    NONE

    1998-12-31

    The importance of protecting water quality and some of the problems associated with mineral development are described. Negative impacts of mining operations such as sedimentation, water disturbances, and water pollution from waste rock and tailings are considered. Mining wastes, types of water pollution from mining, the legacy of acid mine drainage, predicting acid mine drainage, preventing and mitigating acid mine drainage, examples from the past, and cyanide heap-leaching are discussed. The real costs of mining at the Telkwa open pit coal mine are assessed. British Columbia mines that are known for or are potentially acid generating are shown on a map. 32 refs., 10 figs.

  13. Copper isotope fractionation in acid mine drainage

    Kimball, Bryn E; Mathur, Ryan; Dohnalkova, Alice; Wall, A J; Runkel, R L; Brantley, Susan L

    2009-03-01

    We surveyed the Cu isotopic composition of primary minerals and stream water affected by acid mine drainage in a mineralized watershed located in southwestern Colorado, USA. The δ65Cu values (based on 65Cu/63Cu) of local enargite (δ65Cu = -0.01 ± 0.10‰; 2σ) and chalcopyrite (δ65Cu = 0.16 ± 0.10‰) are within the general range of previously reported values for terrestrial primary Cu sulfides (-1‰ < δ65Cu < 1). These mineral samples show lower δ65Cu values than stream waters (δ65Cu = 1.36 - 1.74 ± 0.10‰), with an average isotopic fractionation (quantified as Δaq-mino = δ65Cuaq – δ65Cu min, where Cuaq is leached Cu and Cu mino is the original mineral) of 1.60 ± 0.14‰ and 1.43 ± 0.14‰ for enargite and chalcopyrite, respectively.

  14. Ochre precipitates and Acid Mine Drainage in a mine environment

    Máša, B.; Pulišová, Petra; Bezdička, Petr; Michalková, E.; Šubrt, Jan

    2012-01-01

    Roč. 56, č. 1 (2012), s. 9-14. ISSN 0862-5468 R&D Projects: GA MŠk(CZ) MEB0810136 Grant ostatní: Ministry of Education of the Slovak Republic(SK) VEGA 1/0529/09 Institutional research plan: CEZ:AV0Z40320502 Keywords : ochre precipitate * Acid Mine Drainage ( AMD ) * X-ray diffraction analysis (XRD) * Scanning electron microscopy (SEM) * specific surface area and porosity Subject RIV: CA - Inorganic Chemistry Impact factor: 0.418, year: 2012

  15. Evolution of Acid Mine Drainage Formation in Sulphidic Mine Tailings

    Bernhard Dold

    2014-07-01

    Full Text Available Sulphidic mine tailings are among the largest mining wastes on Earth and are prone to produce acid mine drainage (AMD. The formation of AMD is a sequence of complex biogeochemical and mineral dissolution processes. It can be classified in three main steps occurring from the operational phase of a tailings impoundment until the final appearance of AMD after operations ceased: (1 During the operational phase of a tailings impoundment the pH-Eh regime is normally alkaline to neutral and reducing (water-saturated. Associated environmental problems include the presence of high sulphate concentrations due to dissolution of gypsum-anhydrite, and/or effluents enriched in elements such as Mo and As, which desorbed from primary ferric hydroxides during the alkaline flotation process. (2 Once mining-related operations of the tailings impoundment has ceased, sulphide oxidation starts, resulting in the formation of an acidic oxidation zone and a ferrous iron-rich plume below the oxidation front, that re-oxidises once it surfaces, producing the first visible sign of AMD, i.e., the precipitation of ferrihydrite and concomitant acidification. (3 Consumption of the (reactive neutralization potential of the gangue minerals and subsequent outflow of acidic, heavy metal-rich leachates from the tailings is the final step in the evolution of an AMD system. The formation of multi-colour efflorescent salts can be a visible sign of this stage.

  16. Proceedings of the international land reclamation and mine drainage conference and third international conference on the abatement of acidic drainage. Volume 1: Mine drainage -- SP 06A-94

    Volume 1 of these proceedings is divided into the following sections: Modeling mine water quality; Water treatment with wetlands; Predicting mine water quality; Water treatment--Chemical; Control of acid mine drainage--Wet covers; Site characterization monitoring; Control of acid mine drainage--Alkaline addition; and Mine water geochemistry. Papers dealing with or applicable to coal or uranium mining have been processed separately for inclusion on the data base

  17. Mine drainage treatment

    Golomeova, Mirjana; Zendelska, Afrodita; Krstev, Boris; Golomeov, Blagoj; Krstev, Aleksandar

    2012-01-01

    Water flowing from underground and surface mines and contains high concentrations of dissolved metals is called mine drainage. Mine drainage can be categorized into several basic types by their alkalinity or acidity. Sulfide rich and carbonate poor materials are expected to produce acidic drainage, and alkaline rich materials, even with significant sulfide concentrations, often produce net alkaline water. Mine drainages are dangerous because pollutants may decompose in the environment. In...

  18. Magnetites in acid mine drainage remediation

    Recently we have discovered a catalytic method of production of magnetites at low temperatures using stoichiometric quantities of iron salts. In addition, we have found that the presence of organic chelators can dramatically enhance or inhibit the removal of heavy metals using this technique. Our work with magnetite synthesis at below room temperature was initiated to meet the demand from the US Bureau of Reclamation for the remediation of heavy metals from the Leadville Mine Drainage Tunnel effluent. They presently use a typical high pH treatment process and generate large quantities of sludge that requires extensive dewatering. The Bureau is interested in new cost effective technologies that meet their discharge levels and reduce sludge and the plant footprint. In a combined effort between Los Alamos National Laboratory and New Mexico State University, we are attempting to meet this challenge. Another aspect of our work is the examination of the effect of chelators on the removal of heavy metals from waters using an in-situ method of magnetite formation. Other researchers have used strong oxidants, such as permanganate, to chew up organics before forming magnetites. This was done in the belief that these chelators would inhibit the removal of heavy metals by tying them up and preventing their incorporation into the magnetite matrix. Although perfectly reasonable, in our attempts to quantify the extent of inhibition, we have found this premise to be somewhat simplistic. For example, with Pb2+, Cd2+ and Hg2+, we have found that the presence of chelators, such as EDTA, can either inhibit or enhance the removal efficiencies. In fact, with the appropriate selection of chelators we can chemically separate these three ions using magnetites. We have investigated this effect on several transition metal ions with a variety of chelators. The precise nature of this selectivity is under investigation in our laboratory. (authors)

  19. HANDBOOK FOR CONSTRUCTED WETLANDS RECEIVING ACID MINE DRAINAGE

    In the summer of 1987, a pilot constructed wetland was built at the Big Five Tunnel in Idaho Springs, Colorado. This report details the theory, design and construction of wetlands receiving acid mine drainages, based on the second and third year of operation of this wetland, whic...

  20. Coal acid mine drainage treatment using cement kiln dust

    Edgar Alberto Martínez; Jorge Iván Tobón; Juan Guillermo Morales

    2014-01-01

    Sulphurs are present in different rocks. During mining activities and the sulphur removal processes Acid Mine Drainage (AMD) may be produced, by sulphate ions (SO4 2-) in solution. AMDs are the main source of pollution from mining operations and in Colombia their discharge into natural bodies of water must comply with national environmental regulations (pH between 5 and 9). Cement Kiln Dust (CKD), with calcium carbonate as its main component, from a Cementos Argos S.A. plant was used to neutr...

  1. The Mining Environment Database on abandoned mines, acid mine drainage, and land reclamation

    Laurentian University Library has developed an on-line Mining Environment Database. The database provides references and abstracts to journal articles, books and government reports dealing with acid mine drainage, land reclamation, and abandoned mines. The database, created in 1988, now contains over 7,900 citations on reclamation planning, acid mine drainage, sulfide-based tailings, soil and water contamination, mine closure techniques, and other related topics dealing with mining environment studies. Subject coverage is international and focuses on hard rock mining topics. A stand-alone product for IBM-compatible computers is now available. The database is mastered on four high-density diskettes, and special search software is provided to allow full keyword searching of the database citations. Laurentian has acquired copies of all the materials cited in the database. Access to the on-line database is free of charge, with the exception of long-distance costs, and copy, delivery, or Fax charges for requested material. Suggestions for materials not found in the database and donations of pertinent research information from individuals, corporations, institutions, and government departments are welcomed. Private consulting reports (with the appropriate client approval) are especially welcomed, because this category of research literature cannot be purchased or obtained using normal methods, and is often discarded after a mine property is closed. The process of building a comprehensive research database requires a continuing partnership of information specialists and research users to develop a world class research literature database on mining environment and reclamation

  2. Acid mine-drainage problem of the Patoka River watershed

    Corbett, D.M.

    1969-10-01

    Of the 20,000 acres of cast overburden ground-water aquifers in Pike County, less than 4,000 acres produce acidic water. The remaining 16,000 acres produce nonacidic water, most of which is high in sulfate, and in some instances, high in chloride. The acid mine-drainage problem is a creation of past mining operations for coal, and not one of current origin as many have suspected. Most of the abandoned mine areas that produce sustained flows of acidic water, unaffected by storm runoff, are confined to disturbed areas. Acid contributions from storm runoff are usually many times greater than those from sustained flow, and most generally originate in the compacted 5 to 10% of the areas disturbed by surface mining that accelerate runoff. These compacted areas are essentially comprised of mine-waste piles, haulroads and abandoned railroad grades; open pits, and preparation plant and tipple areas. In the early 1950's several dams were constructed in the area forming lakes and reservoirs that ''bottled up'' the acidic water that would have essentially been discharged by gravity; consequently, the sustained flows from the area are still acidic, as is the water in the several lakes. It is not only impracticable but probably infeasible for the coal industry and society to correct the mine-drainage problem in the Patoka River Watershed without first removing the flushout menace. This flushout hazard can be effectively corrected through a well managed program of draining out the ''bottled up'' acidic water in lakes, ponds, and cast overburden in the areas and covering this material either with nontoxic landfill, or continual inundation with nonacidic water. Stabilization of acidic flows at a reduced level would make feasible the treatment of 5,000,000 gallons of water per day.

  3. OCHRE PRECIPITATES AND ACID MINE DRAINAGE IN A MINE ENVIRONMENT

    BRANISLAV MÁŠA

    2012-03-01

    Full Text Available This paper is focused to characterize the ochre precipitates and the mine water effluents of some old mine adits and settling pits after mining of polymetallic ores in Slovakia. It was shown that the mine water effluents from two different types of deposits (adits; settling pits have similar composition and represent slightly acidic sulphate water (pH in range 5.60-6.05, sulphate concentration from 1160 to 1905 g.dm-3. The ochreous precipitates were characterized by methods of X-ray diffraction analysis (XRD, scanning electron microscopy (SEM and B.E.T. method for measuring the specific surface area and porosity. The dominant phases were ferrihydrite with goethite or goethite with lepidocrocide.

  4. Acid mine drainage systems and metal pollution around the active polymetallic mines in the Eastern Macedonia

    Serafimovski, Todor; Dolenec, Tadej; Tasev, Goran; Dolenec, Matej; Rogan, Nastja

    2007-01-01

    The study of acid mine waters and drainage systems of certain poiymctallic and active mines in the Eastern Macedonia have shown that pH values are in the range 4.0 - 7.8 in the Bucim porphyry Cu-deposit, 4.8 - 5.1 in Pb-Zn mines Sasa and Toranica, and 3.4 - 5.1 in the Zletovo Pb-Zn mine. Both the underground and open pit mines drainage systems on a vertical scale are of several hundreds of meters (from surface to depth) and are affecting the adjacent waters with heavy metals. Determined metal...

  5. Geochemical characterisation of seepage and drainage water quality from two sulphide mine tailings impoundments: Acid mine drainage versus neutral mine drainage

    Heikkinen, P.M.; Raisanen, M.L.; Johnson, R.H.

    2009-01-01

    Seepage water and drainage water geochemistry (pH, EC, O2, redox, alkalinity, dissolved cations and trace metals, major anions, total element concentrations) were studied at two active sulphide mine tailings impoundments in Finland (the Hitura Ni mine and Luikonlahti Cu mine/talc processing plant). The data were used to assess the factors influencing tailings seepage quality and to identify constraints for water treatment. Changes in seepage water quality after equilibration with atmospheric conditions were evaluated based on geochemical modelling. At Luikonlahti, annual and seasonal changes were also studied. Seepage quality was largely influenced by the tailings mineralogy, and the serpentine-rich, low sulphide Hitura tailings produced neutral mine drainage with high Ni. In contrast, drainage from the high sulphide, multi-metal tailings of Luikonlahti represented typical acid mine drainage with elevated contents of Zn, Ni, Cu, and Co. Other factors affecting the seepage quality included weathering of the tailings along the seepage flow path, process water input, local hydrological settings, and structural changes in the tailings impoundment. Geochemical modelling showed that pH increased and some heavy metals were adsorbed to Fe precipitates after net alkaline waters equilibrated with the atmosphere. In the net acidic waters, pH decreased and no adsorption occurred. A combination of aerobic and anaerobic treatments is proposed for Hitura seepages to decrease the sulphate and metal loading. For Luikonlahti, prolonged monitoring of the seepage quality is suggested instead of treatment, since the water quality is still adjusting to recent modifications to the tailings impoundment.

  6. Acid mine drainage as an important mechanism of natural radiation enhancement in mining areas

    Acid mine drainage (AMD) is a world wide problem that occurs whenever sulfidic material is present in association to the mined ore. The acidic waters generated by the process of sulfide minerals oxidation can mobilize important amounts of pollutants and cause significant environmental impacts. The composition of the drainage will depend, on a very large extent, on the mineralogy of the rocks. The purpose of this paper is to demonstrate that acid mine drainage has the potential to enhance the natural levels of environmental radioactivity. The paper revises some strategies to be used in the diagnostic of the problem. General mathematical formulations that can assist on the prediction of the duration of the problem, and the definition of the size of the oxidizing zones in a waste dump are given. A study case on a waste dump of the Pocos de Caldas Uranium Mining Site, Brazil is also presented. (author)

  7. Microbial communities, processes and functions in acid mine drainage ecosystems.

    Chen, Lin-Xing; Huang, Li-Nan; Méndez-García, Celia; Kuang, Jia-Liang; Hua, Zheng-Shuang; Liu, Jun; Shu, Wen-Sheng

    2016-04-01

    Acid mine drainage (AMD) is generated from the oxidative dissolution of metal sulfides when water and oxygen are available largely due to human mining activities. This process can be accelerated by indigenous microorganisms. In the last several decades, culture-dependent researches have uncovered and validated the roles of AMD microorganisms in metal sulfides oxidation and acid generation processes, and culture-independent studies have largely revealed the diversity and metabolic potentials and activities of AMD communities, leading towards a full understanding of the microbial diversity, functions and interactions in AMD ecosystems. This review describes the diversity of microorganisms and their functions in AMD ecosystems, and discusses their biotechnological applications in biomining and AMD bioremediation according to their capabilities. PMID:26921733

  8. Environmental geochemistry of acid mine drainage water at Indus coal mine at Lakhra, Sindh Pakistan

    The annual coal production of Pakistan is about 3,637, 825 tones which is about 6% of the country's energy resources, out of this 1,241, 965 tones of coal was produced/ mined from the Lakhra coal field, District Dadu, Sindh which after the Thar coal field is the second largest coal field of Pakistan. At this coal field more than 58 mining companies are engaged in exploring the hidden wealth of the country. The problem of acid mine drainage, is caused by the passage or seepage of water, through mines where iron disulfides, usually pyrites, are exposed to the oxidizing action of water, air and bacteria, is the main problem faced by the mining companies. The geochemical analysis of acid mine drainage water collected from Indus coal mine no. 6 shows that beside its higher pH, total Dissolved Solids and Sulfates, it also posses higher amount of heavy metals like Cd, Cu, Pb, Co, Ni and Fe. This acid mine drainage water not only damages the mine structures but is also harmful to soil and ecology. (author)

  9. Geochemical Processes Controlling the Generation and Environmental Impacts of Acid Mine Drainage in Semi Arid Conditions

    Magombedze, Chris

    2006-01-01

    This study evaluates the geochemical processes that control the geochemistry of acid mine drainage in semi arid conditions. The central objective is to characterise and understand the evolution of acid mine drainage and its potential environmental impacts on the Mazowe River sub-catchment, in north east Zimbabwe. The work is based on a case study at three neighbouring metal sulphide mines, namely Trojan Nickel Mine, Mazowe Gold Mine and Iron Duke Pyrites.The methodology used in this research ...

  10. Treatment of acid mine drainage and acidic effluents / by Marinda de Beer

    De Beer, Marinda

    2005-01-01

    The scarcity of water in South Africa is exacerbated by pollution of the surface- and ground- water resources. Typical pollutants of the aquatic environment include acid mine drainage and industrial effluents. AMD and acidic effluents can have detrimental effects on mining infrastructure, water reuse options and environmental discharge. As a result, some form of treatment is required at many mine sites. Unless treated, acid water cannot be discharged into public water courses. It ...

  11. Acid mine drainage biogeochemistry at Iron Mountain, California

    Gihring Thomas M

    2004-06-01

    Full Text Available The Richmond Mine at Iron Mountain, Shasta County, California, USA provides an excellent opportunity to study the chemical and biological controls on acid mine drainage (AMD generation in situ, and to identify key factors controlling solution chemistry. Here we integrate four years of field-based geochemical data with 16S rRNA gene clone libraries and rRNA probe-based studies of microbial population structure, cultivation-based metabolic experiments, arsenopyrite surface colonization experiments, and results of intermediate sulfur species kinetics experiments to describe the Richmond Mine AMD system. Extremely acidic effluent (pH between 0.5 and 0.9 resulting from oxidation of approximately 1 × 105 to 2 × 105 moles pyrite/day contains up to 24 g/1 Fe, several g/1 Zn and hundreds of mg/l Cu. Geochemical conditions change markedly over time, and are reflected in changes in microbial populations. Molecular analyses of 232 small subunit ribosomal RNA (16S rRNA gene sequences from six sites during a sampling time when lower temperature (0.8 conditions predominated show the dominance of Fe-oxidizing prokaryotes such as Ferroplasma and Leptospirillum in the primary drainage communities. Leptospirillum group III accounts for the majority of Leptospirillum sequences, which we attribute to anomalous physical and geochemical regimes at that time. A couple of sites peripheral to the main drainage, "Red Pool" and a pyrite "Slump," were even higher in pH (>1 and the community compositions reflected this change in geochemical conditions. Several novel lineages were identified within the archaeal Thermoplasmatales order associated with the pyrite slump, and the Red Pool (pH 1.4 contained the only population of Acidithiobacillus. Relatively small populations of Sulfobacillus spp. and Acidithiobacillus caldus may metabolize elemental sulfur as an intermediate species in the oxidation of pyritic sulfide to sulfate. Experiments show that elemental sulfur which

  12. Acid mine drainage in Australia: its extent and potential future liability. Supervising Scientist Report 125

    In order to better understand the impact of acid drainage in Australia and to provide a basis for assessing long-term management options, the Office of the Supervising Scientist (OSS) and the Australian Centre for Minesite Rehabilitation Research (ACMRR) initiated this study to prepare a status report on acid mine drainage in Australia. The study is supported by the Minerals Council of Australia. The coverage of this study includes all mine sites where sulphidic oxidation in mine wastes or mine workings leads to the release of contaminated drainage with off-site impacts. The objectives of the study were: 1. to quantify and characterise the generation of contaminated drainage by sulphidic oxidation from historic and current mining activities in Australia; 2. to develop a classification scheme to characterise the potential for off-site impacts from sulphidic oxidation in mine wastes; 3. to compare the cost at the national level of managing sulphidic oxidation in mine wastes and any resulting contaminated drainage with other mining and environmental costs; 4. to make recommendations based on the information received to improve the understanding and management of acid mine drainage in Australia. Information was collected on the extent and management of sulphidic oxidation and acid drainage at operating, historic and derelict mines in Australia. Mining operators, environmental officers, industry representatives, state government departments and others were asked about their experience with acid mine drainage and how it is currently managed at operating and historic mine sites. Based on the information collected, the additional cost of managing potentially acid generating wastes at operating mine sites is estimated to be about AUD 60 million per year. Potentially, the financial risk could be much greater if sulphide oxidation and release of pollutants is discovered after mine closure, as was the case for historic sites like Mt Lyell, Rum Jungle or Mt Morgan. The

  13. Acid mine drainage in the Iberian Pyrite Belt: 2. Lessons learned from recent passive remediation experiences

    Ayora Ibáñez, Carlos; Caraballo, Manuel A.; Macías Suárez, Francisco; Roetting, Tobias Stefan; Carrera Ramírez, Jesús; Nieto Liñán, José Miguel

    2013-01-01

    The Iberian Pyrite Belt (IPB), SW Spain and Portugal, contains about 100 abandoned mine wastes and galleries that release acid mine drainages (AMD) to the Tinto and Odiel rivers. In situ passive remediation technologies are especially suitable to remediate the drainages of these orphan sites. However, traditional remediation systems, designed for coal mines, have been demonstrated inefficient to treat the IPB mine waters. Due to their high acidity and metal loads, large amount of solids preci...

  14. Treatment and prevention systems for acid mine drainage and halogenated contaminants

    Jin, Song; Fallgren, Paul H.; Morris, Jeffrey M.

    2012-01-31

    Embodiments include treatments for acid mine drainage generation sources (10 perhaps by injection of at least one substrate (11) and biologically constructing a protective biofilm (13) on acid mine drainage generation source materials (14). Further embodiments include treatments for degradation of contaminated water environments (17) with substrates such as returned milk and the like.

  15. Development of a new methodology for mitigating acid mine drainage (AMD) at reclaimed surface mines

    A 1.2 hectare (ha) experimental site located on a 14.5 ha reclaimed surface mine in Greene County, PA was injected with a 141 cubic meters (m3) of fly ash and fluidized bed combustion (FBC) ash grout that included acid mine drainage (AMD) sludge. An evaluation of this AMD abatement approach by the Bureau of Mines found that the average net acidity and concentrations of several metal ions at the discharge seep and monitoring wells decreased after grouting. Changes in metal concentrations were assumed to be related to alkaline addition and/or encapsulation. Initial results indicate that this technique is potentially an effective AMD abatement method

  16. Modelling of acid mine drainage (AMD in columns

    C. M. Bernardes de Souza

    2011-09-01

    Full Text Available A model is proposed in this paper to describe the generation of acid mine drainage (AMD in leaching columns. The model considers: (i Water flow through the column, which is calculated using the 1 - D analytic solution of the Richards' equation assuming the existence of a similarity relationship between the water retention function and the water content profiles at a given time; and (ii Pyrite oxidation weighted by microbiological effects occurring in spherical particles according to the shrinking core model. Mass balances of oxygen and pyrite were derived in order to evaluate the intrinsic oxidation rate and the pyrite fraction reacted with time and column position. The model was used to simulate a six month operation of a leaching column, which comprised successive weekly cycles of dry and wet periods. Simulation results demonstrated that AMD generation is strongly affected by the presence of microorganisms. A relative deviation of 5% between simulation and experimental data was obtained.

  17. Fly ash grouts for remediation of acid mine drainage

    An engineering investigation into the use of electric utility wastes for grouting acidic mine spoil resulting from coal extraction has been undertaken. Laboratory investigations into the physical and chemical properties of various grout mixtures and grouted spoil materials are underway. Grout mixtures are placed in columns and permeated with distilled water. The hydraulic conductivity of the grout was measured. The effect of the high alkaline ashes on the acidic drainage is of particular interest. This series of experiments provided information so that the most favorable grout (low hydraulic conductivity and high alkalinity) could be selected for injection into acidic spoil material. Both standard combustion and fluidized bed ashes were tested. Grout mixtures include ashes, scrubber sludge, lime, bentonite and/or kaolinite. Permeabilities of the mixtures averaged approximately 1.OE-4 cm/sec. A second series of laboratory experiments consists of grouting large diameter drums of acidic spoil with the fly ash grouts. The drums have been constructed and filled with acidic spoil material. The ungrouted infiltration rates have been determined and the resulting effluents chemically analyzed

  18. Uranium in acidic mine drainage at the former Ogoya Mine in Ishikawa Prefecture of Japan

    Uranium in acidic mine drainage from the former Ogoya Mine in Ishikawa Prefecture, Japan, and in neutral surface waters from its surrounding rivers was investigated from the viewpoint of radioactive disequilibrium in the uranium decay series. Water samples were periodically collected from the mine pithead and its surrounding rivers and their U isotopes (238U and 234U) were measured together with chemical components. The 238U concentrations in the water samples varied widely from 0.0036 to 0.78 mBq/L with a factor of about 200. High 238U concentrations were observed in the strongly acidic drainage (pH: around 3.5) from the pithead and the 234U/238U activity ratios showed significant values of as high as 10-15. By taking into account of the measurement of Th isotopes, it appeared that probable processes controlling the high 234U/238U activity ratios in acidic mine drainage were due to that the acidic water flowing from the mine pithead was formed only in the upper water layer of the pits and 234U was preferentially leached in the deeper underground water under the neutral and reducing conditions. (author)

  19. Acid mine drainage abatement resulting from pressure grouting of buried bituminous mine spoils

    A 37 acre surface coal mine located in Clinton County, PA, USA, was mined and reclaimed between 1974 and 1977. Buried pyrite-rich pit floor cleanings and tipple refuse were found to be producing severe acid mine drainage. The pyritic material is located in discrete piles or pods in the backfill. The pods and the resulting contaminant plumes were initially defined using geophysical techniques and confirmed by drilling. The approach taken was to use a cementitious grout, composed of fluidized bed combustion ash and water, which would be placed in a manner which would prevent water and oxygen from contacting the pyritic materials. Statistically significant water quality improvements have been noted as a result of the grouting. After four years of post-grouting monitoring, reductions in concentrations of most of the mine drainage parameters range from 40 to 90%. 12 refs., 1 fig., 4 tabs

  20. Effectiveness of a constructed wetland for acid mine drainage reclamation

    Acid mine drainage (AMD) from an abandoned coal mine in southcentral Kentucky had pH levels as low as 2.5 and iron concentrations as high as 630 mg/L. In the summer of 1992, the SCS constructed a wetland system to treat the AMD that involved use of both physical and biological treatment. The AMD was fed into three anoxic limestone beds, followed by an aeration pond, before entering a series of four cattail cells and a polishing pond. Flow of AMD was initiated in the fall of 1992, and chemical and biological monitoring were conducted throughout the winter months. Chemical analysis of the water along the flow path of the AMD during the first six months of operation indicated that the limestone beds improved the pH substantially, and that most of the metals were removed prior to the water entering the cattail cells. The effectiveness of the wetland system to improve water quality also was monitored using the cladoceran (Ceriodaphnia dubia) survival and reproduction test. Determination of toxic levels indicated a substantial improvement in water quality below the limestone beds, and a slight decrease in toxicity throughout the cattail cells. However, toxic levels stayed the same or increased in the polishing pond. Water quality monitoring will continue through the growing season of 1993 to assess the impact of plant growth on the reclamation of the AMD

  1. Role of biologically assisted pyrrhotite oxidation in acid mine drainage

    Water contaminated by acidic mine drainage (AMD) from base metal tailings and waste rock is a serious environmental problem. Previous studies have focused on pyrite as the principal acid producing mineral. In this work, the significance of pyrrhotite (Fe1-xS) oxidation, both chemical and biochemical, on the acid generation process is discussed. Chemical and biochemical kinetic studies of pyrrhotite oxidation were conducted in pneumatically mixed, internal split flow reactors. Controlling variables included the specific surface area, temperature, pH, partial pressure of oxygen, and co-oxidation with pyrite. Bacterial oxidations, using Thiobacillus ferrooxidans as inoculant. included the inherent metabolic rate and cell sorption equilibria on the ore surface. Mathematical models were derived to couple the kinetics with oxygen mass transfer. The mass transport model combined mechanisms based on the shrinking radius (fine particles) and the shrinking reactive front (massive sulfides) concepts. The objective of the research was the application of fundamental kinetic and physical data to field conditions for simulating both the rate of mineral oxidation and simulating pore water quality

  2. Major hydrogeochemical processes in an Acid Mine Drainage affected estuary

    Highlights: • Mixing of acid riverine water with alkaline seawater was studied in an estuary. • Combination of data and geochemical tools allowed modeling the water mixing. • The main geochemical processes were identified and for the first time quantified. • Water chemistry is the result of mixing, dissolution-precipitation and sorption. • Main reactions: gypsum and calcite dissolution and Al and Fe solids precipitation. - Abstract: This study provides geochemical data with the aim of identifying and quantifying the main processes occurring in an Acid Mine Drainage (AMD) affected estuary. With that purpose, water samples of the Huelva estuary were collected during a tidal half-cycle and ion–ion plots and geochemical modeling were performed to obtain a general conceptual model. Modeling results indicated that the main processes responsible for the hydrochemical evolution of the waters are: (i) the mixing of acid fluvial water with alkaline ocean water; (ii) precipitation of Fe oxyhydroxysulfates (schwertmannite) and hydroxides (ferrihydrite); (iii) precipitation of Al hydroxysulfates (jurbanite) and hydroxides (amorphous Al(OH)3); (iv) dissolution of calcite; and (v) dissolution of gypsum. All these processes, thermodynamically feasible in the light of their calculated saturation states, were quantified by mass-balance calculations and validated by reaction-path calculations. In addition, sorption processes were deduced by the non-conservative behavior of some elements (e.g., Cu and Zn)

  3. Iron removal from acid mine drainage by wetlands

    Neutralization of acid mine drainage (AMD) in man-made cattail (Typha) wetlands was investigated over a four-year period utilizing experimental models constructed in a greenhouse. A naturally occurring AMD (430 mg/L Fe, 5 mg/L Mn, 2,900 mg/L sulfate, pH 2.75) was collected in the field and added to the greenhouse wetlands at 60.5 L/day. Monthly water samples from four depths (10, 20, 30, and 40 cm) were obtained from the influent, midpoint, and effluent locations of the wetland. During the first year of AMD treatment, near neutral pH (6.5) and anoxic conditions (minus300 mV) were observed in subsurface sediments of wetlands. The wetlands retained an estimated 65% of the total applied iron in the first year, primarily in the exchangeable, organically bound, and oxide form. During later years, 20 to 30% of the influent iron was retained predominantly as precipitated oxides. Iron sulfides resulting form sulfate reduction accounted for less than 5% of the iron retained, and were recovered primarily as monosulfides during the first year and as disulfides in the fourth year. Improvement in effluent pH was primarily attributed to limestone dissolution in the anaerobic subsurface sediments, which decreased with time. Constructed wetlands exhibit finite lives for effective AMD treatment and provisions should be made for their periodic rejuvenation or replacement

  4. Proceedings of the international land reclamation and mine drainage conference and third international conference on the abatement of acidic drainage. Volume 2: Mine drainage -- SP 06B-94

    Volume 2 of these proceedings is divided into six sessions: Mine drainage--Case studies (5 papers); Control of mine drainage--General (6); Control of mine drainage--Dry covers (6); Mine hydrology (6); a Poster session of miscellaneous papers (24); and a section of 59 abstracts. 78 papers dealing with or applicable to coal or uranium mining have been processed separately for inclusion on the data base

  5. Use of electric utility wastes for control of acid mine drainage

    Placement of fly ash in abandoned, reclaimed or active surface coal mines is intended to reduce the amount of acid mine drainage (AMD) produced. Water quality changes have been monitored at three surface mines where fly ash grout was injected after reclamation. Also, a laboratory column leaching study exposed samples of fly ash to AMS surrogates for 30 to 180 days. Changes in acidity and potential release of heavy metals were primary areas of interest. Both field and laboratory studies indicate that fly ash may be an economical reagent for ameliorating acid mine drainage without adverse environmental effects. 13 refs

  6. Acid Mine Drainage and Heavy Metal Pollution from Solid Waste in the Tongling Mines, China

    XU Xiaochun; XIE Qiaoqin; CHEN Fang; WANG Jun; WU Wentao

    2008-01-01

    Based on investigation of the characteristics of solid waste of two different mines, the Fenghuangshan copper mine and the Xinqiao pyrite mine in Tongling, Anhui province in central-east China, the possibility and the differences of acid mine drainage (AMD) of the tailings and the waste rocks are discussed, and the modes of occurrence of heavy metal elements in the mine solid waste are also studied. The Fenghuangshan copper mine hardly produces AMD, whereas the Xinqiao pyrite mine does and there are also differences in the modes of occurrence of heavy metal elements in the tailings. For the former, toxic heavy metals such as Cu, Pb, Zn, Cd, As and Hg exist mostly in the slag mode, as compared to the latter, where the dcoxidization mode has a much higher content, indicating that large amounts minerals in the waste rocks have begun to oxidize at the earth surface. AMD is proved to promote the migration and spread of the heavy metals in mining waste rocks and lead to environmental pollution of the surroundings of the mine area.

  7. LABORATORY EVALUATION OF ZERO-VALENT IRON TO TREAT GROUNDWATER IMPACTED BY ACID MINE DRAINAGE

    The generation and release of acidic, metal-rich water from mine wastes continues to be an intractable environmental problem. Although the effects of acid mine drainage (AMD) are most evident in surface waters, there is an obvious need for developing cost-effective approaches fo...

  8. Injection of alkaline ashes into underground coal mines for acid mine drainage abatement

    The injection of alkaline coal combustion waste products into abandoned underground coal mines for acid mine drainage (AMD) abatement has obvious conceptual appeal. This paper summarizes the findings of the baseline hydrogeologic and water quality evaluations at two sites--one in West Virginia and one in Maryland--where field demonstrations of the technique are being pursued in cooperative efforts among State and Federal agencies and/or private companies. The West Virginia site produces severe AMD from three to seven AMD sources that are spaced over about a 1.2 km stretch of the down-dip side of the mine workings. By completely filling the most problematic portion of the mine workings with coal combustion ashes, the State expects that the costs and problems associated with AMD treatment will be greatly reduced. At the Maryland site, it is expected that the AMD from a relatively small target mine will be eliminated completely by filling the entire mine void with a grout composed of a mixture of fly ash, fluidized-bed combustion ash, and flue gas desulfurization sludge. This project will also demonstrate the potential cost-effectiveness of the technique at other sites, both for the purpose of AMD remediation and control of land subsidence

  9. Bioelectrochemical treatment of acid mine drainage dominated with iron

    Highlights: ► Treatment of AMD dominated with Fe is problematic due to its low pH. ► The goal of AMD treatment is pH increasing and Fe controlled removal. ► An MFC could fulfill both these requirements by treating AMD at the aerated cathode. ► The performance was proportional to the charge transfer up to 880 C. ► The treated AMD met the discharge limits both for Fe (>99% recovery) and pH (7.9). - Abstract: Treatment of acid mine drainage (AMD) dominated with iron (Fe), the most common metal, is a long-term expensive commitment, the goal of which is to increase the pH and remove Fe. In the present study, a proton exchange membrane microbial fuel cell (MFC) showed promise for the efficient treatment of an AMD dominated with ferric iron (pH 2.4 ± 0.1; 500 mg L−1 Fe3+). Briefly, Fe3+ was reduced to Fe2+ at the cathode of the MFC, followed by Fe2+ re-oxidation and precipitation as oxy(hydroxi)des. Oxygen reduction and cation transfer to the cathode of the MFC further caused a rise in pH. A linear relationship was observed between the charge transferred in the MFC and the performance of the system up to 880 C. Optimal conditions were found at a charge of 662 C, achieved within 7 d at an acetate concentration of 1.6 g L−1 in a membrane MFC. This caused the pH to rise to 7.9 and resulted in a Fe removal of 99%. Treated effluent met the pH discharge limits of 6.5–9. The maximum power generation achieved under these conditions averaged 8.6 ± 2.3 W m−3, which could help reduce the costs of full-scale bioelectrochemical treatment of AMD dominated with Fe.

  10. Injection of FGD Grout to Abate Acid Mine Drainage in Underground Coal Mines

    Acid Mine Drainage (AMD) from abandoned underground coal mines in Ohio is a concern for both residents and regulatory agencies. Effluent from these mines is typically characterized by low pH and high iron and sulfate concentrations and may contaminate local drinking-water supplies and streams. The objective of this project is to demonstrate the technical feasibility of injecting cementitious alkaline materials, such as Flue Gas Desulfurization (FGD) material to mitigate current adverse environmental impacts associated with AMD in a small, abandoned deep mine in Coshocton County Ohio. The Flue Gas Desulfurization material will be provided from American Electric Power's (AEP) Conesville Plant. It will be injected as a grout mix that will use Fixated Flue Gas Desulfurization material and water. The subject site for this study is located on the border of Coshocton and Muskingum Counties, Ohio, approximately 1.5 miles south-southwest of the town of Wills Creek. The study will be performed at an underground mine designated as Mm-127 in the Ohio Department of Natural Resources register, also known as the Roberts-Dawson Mine. The mine operated in the mid-1950s, during which approximately 2 million cubic feet of coal was removed. Effluent discharging from the abandoned mine entrances has low pH in the range of 2.8-3.0 that drains directly into Wills Creek Lake. The mine covers approximately 14.6 acres. It is estimated that 26,000 tons of FGD material will be provided from AEP's Conesville Power Plant located approximately 3 miles northwest of the subject site

  11. Historical overview and future directions of the microbial role in the acidic coal mine drainage system

    Bacteria have been implicated and analyzed at every step in the production of acidic coal mine drainage (AMD). This review paper provides detailed information about microbial studies in mines, laboratory settings, waste piles, ground water, receiving streams, and downstream rivers and lakes. Research on AMD treatment, beneficial uses, and seasonal variability is also reviewed. 102 refs

  12. Integrated acid mine drainage management using fly ash.

    Vadapalli, Viswanath R K; Gitari, Mugera W; Petrik, Leslie F; Etchebers, Olivier; Ellendt, Annabelle

    2012-01-01

    Fly Ash (FA) from a power station in South Africa was investigated to neutralise and remove contaminants from Acid Mine Drainage (AMD). After this primary treatment the insoluble FA residue namely solid residue (SR) was investigated as a suitable mine backfill material by means of strength testing. Moreover, SR was used to synthesise zeolite-P using a two-step synthesis procedure. Furthermore, the zeolite-P was investigated to polish process water from the primary FA-AMD reaction. The main objective of this series of investigations is to achieve zero waste and to propose an integrated AMD management using FA. Fly Ash was mixed with AMD at various predetermined FA-AMD ratios until the mixtures achieved circumneutral pH or higher. The supernatants were then analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Ion Chromatography (IC) for cations and anions respectively. The physical strength testing of SR was carried out by mixing it with 3% Ordinary Portland Cement (OPC) and curing for 410 days. Synthesis of zeolite-P using SR was carried out by two step synthesis procedure: ageing for 24 hours followed by a mild hydrothermal synthesis at 100°C for 4 days. The polishing of process water from primary AMD treatment using FA was ascertained by mixing the process water with zeolite at a liquid to solid ratio of 100:1 for 1 hour. The results indicated that FA can be successfully used to ameliorate AMD. High removal of major AMD contaminants Fe, Al, Mg, Mn and sulphate was achieved with the ash treatment and trace elements such as Zn, Ni, Cu and Pb were also removed by the FA. Strength testing over 410 days indicated that the material gained strength over the testing period. The maximum unconfined compressive strength and elastic modulus was observed to be approximately 0.3 MPa and 150 Mpa respectively. The X-ray diffraction (XRD) analysis of the synthesized product indicated that SR was successfully converted into zeolite-P with some mullite phase

  13. Acid mine drainage from the Panasqueira mine and its influence on Zêzere river (Central Portugal)

    Candeias, Carla; Ávila, Paula Freire; Ferreira da Silva, Eduardo; Ferreira, Adelaide; Salgueiro, Ana Rita; Teixeira, João Paulo

    2014-11-01

    The Panasqueira hydrothermal mineralization, located in central Portugal, is the biggest Sn-W deposit of the Western Europe. The main evidences of the mining exploitation and ore treatment operations are testified with huge tailings, mainly, in the Rio and Barroca Grande areas. The mining and beneficiation processes, at the site, produces metal rich mine wastes. Oxidation of sulfides tailings and flow from open impoundments are responsible for the mobilization and migration of metals from the mine wastes into the environment. Acid mine drainage (AMD) discharged from Rio tailing has a pH around 3 and high metal concentrations. In Zêzere river, Fe and As are the most rapidly depleted downstream from AMD once As adsorbs, coprecipitate and form compounds with iron oxyhydroxides. The Zêzere river waters are oversaturated with respect to kaolinite and goethite and ferrihydrite can precipitate on stream with a near-neutral pH. At sites having low pH the dissolved Fe species in the water, mainly, occur as sulfate complexes due to a high SO4 concentration. Melanterite (Fe2+(SO4)·7(H2O)) and minor amounts of rozenite (Fe2+(SO4)·4(H2O)) and szomolnokite (Fe2+(SO4)·(H2O)) were observed on Rio tailing basement.

  14. Investigation of the acid mine drainage potential of the Kopanang rock dump, Vaal Reefs / Charl Labuschagne

    Labuschagne, Charl

    2008-01-01

    The Kopanang rock dump is one of several rock dumps in the Vaal Reefs gold mining area that may have an impact on the surface and groundwater quality. Few Acid Mine Drainage (AMD) studies exist on rock dumps in the South African gold industry due to the overwhelming acid generation from slime dams. Due to the existence of sulfide minerals in the Kopanang rock dump, there is a possibility that acid generation can occur, depending on the mineralogical composition of the ...

  15. Macroinvertebrate response to acid mine drainage: community metrics and on-line behavioural toxicity bioassay

    The hypothesis is tested that toxicity of acid mine drainage can be detected by a selection of existing macroinvertebrate community and bioindicator metrices supplemented by toxicity tests with the local mosquitofish Gambusia holbrooki Girard and the shrimp Atyaephyra desmaresti Millet. The behavioural responses of A. desmaresti to acid mine drainage were recorded in the Multispecies Freshwater Biomonitor[reg], based on behaviour and survival as parameters. Bioassessment methods were based on community diversity, structure, function, and bioindicators and supplemented by chemical analysis (temperature, pH, metals). The Biological Monitoring Working Party adapted for the Iberian Peninsula, the number of predators (Coleoptera, Hemiptera) and the number of Ephemeroptera and Trichoptera taxa differentiated the sites well. The on-line toxicity test revealed pH-dependent acute toxicity of the acid mine drainage for the shrimp (LC50-48 h: pH-AMD=5.8) and a pH- dependent decrease in locomotory activity with the lowest-observed-response-times (LORTs) within 5 h of exposure. Shrimp were more sensitive to acid mine drainage than fish (LC50-48 h: pH-AMD=4.9). A new multimetric index combining toxicity testing and bioassessment methods is proposed. - Toxicity of acid mine drainage was evaluated by macroinvertebrate bioassessment and a new on-line rapid behavioural toxicity test with Atyaephyra desmaresti (Crustacea)

  16. Impact of acid mine drainages on surficial waters of an abandoned mining site.

    García-Lorenzo, M L; Marimón, J; Navarro-Hervás, M C; Pérez-Sirvent, C; Martínez-Sánchez, M J; Molina-Ruiz, José

    2016-04-01

    Weathering of sulphide minerals produces a great variety of efflorescences of soluble sulphate salts. These minerals play an important role for environmental pollution, since they can be either a sink or a source for acidity and trace elements. This paper aims to characterise surface waters affected by mining activities in the Sierra Minera of Cartagena-La Union (SE, Spain). Water samples were analysed for trace metals (Zn, Cd, Pb, Cu, As and Fe), major ions (Na(+), K(+), Ca(2+) and Mg(2+)) and anions (F(-), Cl(-), NO3 (-), CO3 (2-), SO4 (2-)) concentrations and were submitted to an "evaporation-precipitation" experiment that consisted in identifying the salts resulting from the evaporation of the water aliquots sampled onsite. Mineralogy of the salts was studied using X-ray diffraction and compared with the results of calculations using VISUAL MINTEQ. The study area is heavily polluted as a result of historical mining and processing activities that has produced large amount of wastes characterised by a high trace elements content, acidic pH and containing minerals resulting from the supergene alteration of the raw materials. The mineralogical study of the efflorescences obtained from waters shows that magnesium, zinc, iron and aluminium sulphates predominate in the acid mine drainage precipitates. Minerals of the hexahydrite group have been quantified together with minerals of the rozenite group, alunogen and other phases such as coquimbite and copiapite. Calcium sulphates correspond exclusively to gypsum. In a semiarid climate, such as that of the study area, these minerals contribute to understand the response of the system to episodic rainfall events. MINTEQ model could be used for the analysis of waters affected by mining activities but simulation of evaporation gives more realistic results considering that MINTEQ does not consider soluble hydrated salts. PMID:26347422

  17. Use of Natural and Applied Tracers to Guide Targeted Remediation Efforts in an Acid Mine Drainage System, Colorado Rockies, USA

    Rory Cowie; Williams, Mark W.; Mike Wireman; Robert L. Runkel

    2014-01-01

    Stream water quality in areas of the western United States continues to be degraded by acid mine drainage (AMD), a legacy of hard-rock mining. The Rico-Argentine Mine in southwestern Colorado consists of complex multiple-level mine workings connected to a drainage tunnel discharging AMD to passive treatment ponds that discharge to the Dolores River. The mine workings are excavated into the hillslope on either side of a tributary stream with workings passing directly under the stream channel. ...

  18. Remediation of acid mine drainage from the Santa Fe tin mine, Bolivia

    Calvo, Daniel; Zamora Echenique, Gerardo; Alfonso, Pura; Casado, Jordi; Trujillo, Elvys; Jiménez-Franco, Abigail; Garcia-Valles, Maite

    2015-04-01

    The Santa Fe mine, department of Oruro, is located in the Andean Tin belt, is exploited for tin, zinc, lead and silver. This in an underground mine mined up to the -108 level. Today it is only mined up to the -50 level. Under this level the table water covers the mine. Water reaches the surface with a very acidic composition, with a high content in potentially toxic elements. This water drains directly to the Santa Fe River and contribute to the pollution present in this river that directly affect to the aquatic communities. In addition, population of this area have problems in the supply of drinking water, so remediation by obtaining cleaning water is a priority for this area. This study presents a neutralization-precipitation treatment with lime to the acid water inside the mine. The ore mineralogy of the Santa Fe mined deposit consists mainly in cassiterite, pyrite, sphalerite, galena, arsenopyrite argentite and sulphosalts. The host mineral is mainly quartz, with a minor content in feldspars and tourmaline. Alteration minerals as alunite, goethite and pumbojarosite are abundant and indicate the occurrence of reactions that lead to the formation of acid mine drainage. The mean pH of water drained from the Santa Fe mine is 2.2 and chemical analyses show high contents in potentially toxic elements: 27-295 ppm Zn, 0.05-0.2 ppm Pb, 0.06-0.09 ppm Cd, 04-0.12 ppm Cu, 113-165 ppm Fe, 4 ppm Mn and 564-664 ppm S. As and Sb were under 0.5 ppm. A settler tank inside the mine was designed by means of seal a selected gallery to clean the mine water. The function of this gallery is to sediment the sludge resulting from the neutralization - precipitation treatment process to obtain a clear water overflow continuously to the outside. The neutralization tests indicate that 0.65g/L of lime and 2ml of flocculant should be added to neutralize water up to pH 6-7. A flow rate of 80 L /s was considered. After a geotechnical study, a chamber located in the mine was selected to locate

  19. Quality and quantity of the alkaline amendments needed to prevent acid mine drainage

    Control of acid mine drainage requires not only treatment of existing drainage but prevention of future acidic drainage. Waste rock exposed during coal mining and processing may contain up to 6% pyritic sulfur. These rocks may have little inherent neutralization capacity and appear to be very long lived acid generators. This paper summarizes recent research into the influence of additives to coal waste rock for the prevention of acidic mine drainage. Methods have been developed whereby additives can be evaluated using an extended acid-base accounting method and by Soxhlet extraction methods. The former method provides a means for gross determination of dose and the latter method provides some kinetic information on acid release. In addition to the evaluation of the effect of ameliorants on acidity, metal release has also been examined. Mass balances on sulfur, iron manganese and aluminum are used to discuss the nature of the treatment chemical reactions. The economics and efficacy of various treatment products (lime, combustion ash, kiln dust, and phosphate in particular) are discussed

  20. Integrative Bioassessment of Acid Mine Drainage Impacts on the Upper Powell River Watershed, Southwestern Virginia

    Soucek, David John

    2001-01-01

    Acid mine drainage (AMD), a result of oxidation of minerals containing reduced forms of sulfur (pyrites, sulfides) upon exposure to water and oxygen, is an environmental problem associated with abandoned mined lands (AML). Numerous studies have documented the impacts of AMD upon aquatic communities within acidified stream reaches; these impacts include reduced taxonomic richness and abundance, and/or a shift from pollution sensitive to pollution tolerant species. This dissertation comprises ...

  1. REMOVAL OF NICKEL WITH ELEMENTAL IRON, WHICH IS COMMONLY FOUND IN ACID MINE DRAINAGE

    Maria A. Liendo; Carlos H. Sampaio; Gelsa E. Navarro

    2011-01-01

    The aim of this study was to evaluate the Ni2+ removal with commercial iron particles. That cation is often found in acid mine drainage (AMD), which is one of the most serious environmental problems in the mining industry that affects natural waters sources. Laboratory tests were performed with commercial iron and synthetic solutions containing Ni2+, to observe not only the kinetic of the removal but the equilibrium data as well. The obtained data showed that these followed the Langmuir adsor...

  2. Metal cycling during sediment early diagenesis in a water reservoir affected by acid mine drainage

    Torres, Ester; Ayora, Carlos; Canovas, C. R.;

    2013-01-01

    The discharge of acid mine drainage (AMD) into a reservoir may seriously affect the water quality. To investigate the metal transfer between the water and the sediment, three cores were collected from the Sancho Reservoir (Iberian Pyrite Belt, SW Spain) during different seasons: turnover event...

  3. TREATMENT OF ACID MINE DRAINAGE BY THE ALUMINA-LIME-SODA PROCESS

    The alumina-lime-soda process is a chemical desalination process for waters in which the principal sources of salinity are sulfate salts and has been field tested at the Commonwealth of Pennsylvania's Acid Mine Drainage Research Facility, Hollywood, Pennsylvania, as a method to r...

  4. Metals Recovery from Acid Mine Drainage and Possibilities for their Utilization

    Michalková, E.; Schwarz, M.; Pulišová, Petra; Máša, B.; Sudovský, P.

    2013-01-01

    Roč. 22, č. 4 (2013), s. 1111-1118. ISSN 1230-1485 R&D Projects: GA MŠk 7AMB12SK155 Institutional support: RVO:61388980 Keywords : acid mine drainage * ferric pigments * adsorbent Subject RIV: CA - Inorganic Chemistry Impact factor: 0.600, year: 2013

  5. COMPOST-FREE BIOREACTOR TREATMENT OF ACID ROCK DRAINAGE LEVIATHAN MINE, CALIFORNIA INNOVATIVE TECHNOLOGY EVALUATION REPORT

    As part of the Superfund Innovative Technology Evaluation (SITE) program, an evaluation of the compost-free bioreactor treatment of acid rock drainage (ARD) from the Aspen Seep was conducted at the Leviathan Mine Superfund site located in a remote, high altitude area of Alpine Co...

  6. A full-scale porous reactive wall for prevention of acid mine drainage

    The generation and release of acidic drainage containing high concentrations of dissolved metals from decommissioned mine wastes is an environmental problem of international scale. A potential solution to many acid drainage problems is the installation of permeable reactive walls into aquifers affected by drainage water derived from mine waste materials. A permeable reactive wall installed into an aquifer impacted by low-quality mine drainage waters was installed in August 1995 at the Nickel Rim mine site near Sudbury, Ontario. The reactive mixture, containing organic matter, was designed to promote bacterially mediated sulfate reduction and subsequent metal sulfide precipitation. The reactive wall is installed to an average depth of 12 feet (3.6 m) and is 49 feet (15 m) long perpendicular to ground water flow. The wall thickness (flow path length) is 13 feet (4 m). Initial results, collected nine months after installation, indicate that sulfate reduction and metal sulfide precipitation is occurring. The reactive wall has effectively removed the capacity of the ground water to generate acidity on discharge to the surface. Calculations based on comparison to previously run laboratory column experiments indicate that the reactive wall has potential to remain effective for at least 15 years

  7. BONE MEAL AS ALTERNATIVE TREATMENT FOR ACIDIC AND METAL CONTAMINATED ACID MINE DRAINAGE WATER EFFLUENT: LAB SCALE

    Carolyn Payus; Olga David; Moh Pak Yan

    2014-01-01

    The typical methods of treatment for acidic and metal contaminated water effluent such as the Acid Mine Drainage (AMD) will always focus on either civil engineering methods, such as disposal, excavation, drainage and encapsulation or process based technologies such as effluent washing and treatment. These techniques are not environmental friendly, costly and unsustainable, thus environmental damaging. Nowadays, there is a growing need for an alternative remediation treatment that is innovativ...

  8. A review of acid drainage from waste rock dumps and mine sites (Australian and Scandinavia)

    This report reviews the literature from Australia and Scandinavia on acid drainage from pyritic waste rock dumps with an emphasis on measurements and theory of processes that control the rage of oxidation and the release of pollutants. Conditions within waste rock dumps have been measured at several mine sites and a range of rehabilitation treatments have been tried to reduce the release of pollutants. A number of models have been proposed to calculate air flow, water transport and geochemistry. The data and experience at the mine sites are compared with predictions of the models. Details of Australian and Swedish mine sites where waste rock is a source of acid drainage are described in the Appendices. 92 refs., 2 tabs., 10 figs

  9. Study of environmental pollution and mineralogical characterization of sediment rivers from Brazilian coal mining acid drainage

    Silva, Luis F.O., E-mail: felipeqma@hotmail.com [Environmental Science and Nanotechnology Department, Institute of Environmental Research and Human Development – IPADH, Capivari de Baixo, Santa Catarina (Brazil); Laboratory of Environmental Researches and Nanotechnology Development, Centro Universitário La Salle, Victor Barreto, 2288 Centro 92010-000, Canoas, RS (Brazil); Fdez- Ortiz de Vallejuelo, Silvia; Martinez-Arkarazo, Irantzu; Castro, Kepa [Department of Analytical Chemistry, University of the Basque Country (EHU/UPV), P.O. Box 644, 48080 Bilbao, Basque Country (Spain); Oliveira, Marcos L.S. [Environmental Science and Nanotechnology Department, Institute of Environmental Research and Human Development – IPADH, Capivari de Baixo, Santa Catarina (Brazil); Sampaio, Carlos H.; Brum, Irineu A.S. de [Universidade Federal do Rio Grande do Sul, Escola de Engenharia, Departamento de Metalurgia, Centro de Tecnologia, Av. Bento Gonçalves, 9500, Bairro Agronomia, CEP: 91501-970, Porto Alegre, RS (Brazil); Leão, Felipe B. de; Taffarel, Silvio R. [Laboratory of Environmental Researches and Nanotechnology Development, Centro Universitário La Salle, Victor Barreto, 2288 Centro 92010-000, Canoas, RS (Brazil); Madariaga, Juan M. [Department of Analytical Chemistry, University of the Basque Country (EHU/UPV), P.O. Box 644, 48080 Bilbao, Basque Country (Spain)

    2013-03-01

    Acid drainage from coal mines and metal mining is a major source of underground and surface water contamination in the world. The coal mining acid drainage (CMAD) from mine contains large amount of solids in suspension and a high content of sulphate and dissolved metals (Al, Mn, Zn, Cu, Pb, Fe, etc.) that finally are deposited in the rivers. Since this problem can persist for centuries after mine abandonment, it is necessary to apply multidisciplinary methods to determine the potential risk in a determinate area. These multidisciplinary methods must include molecular and elemental analysis and finally all information must be studied statistically. This methodology was used in the case of coal mining acid drainage from the Tubarao River (Santa Catarina, Brazil). During molecular analysis, Raman Spectroscopy, electron bean, and X-ray diffraction (XRD) have been proven very useful for the study of minerals present in sediment rivers near this CMAD. The obtained spectra allow the precise identification of the minerals as jarosite, quartz, clays, etc. The elemental analysis (Al, As, Fe, K, Na, Ba, Mg, Mn, Ti, V, Zn, Ag, Co, Li, Mo, Ni, Se, Sn, W, B, Cr, Cu, Pb and Sr) was realised by inductively coupled plasma mass spectrometry (ICP-MS). Statistical analysis (Principal Component Analysis) of these dates of concentration reveals the existence of different groups of samples with specific pollution profiles in different areas of the Tubarao River. Highlights: ► Increasing coal drainage sediments geochemical information will increase human health information in this area. ► Brazilian coal mining information will increase recuperation planning information. ► The nanominerals showed strong sorption ability to aqueous hazardous elements.

  10. Study of environmental pollution and mineralogical characterization of sediment rivers from Brazilian coal mining acid drainage

    Acid drainage from coal mines and metal mining is a major source of underground and surface water contamination in the world. The coal mining acid drainage (CMAD) from mine contains large amount of solids in suspension and a high content of sulphate and dissolved metals (Al, Mn, Zn, Cu, Pb, Fe, etc.) that finally are deposited in the rivers. Since this problem can persist for centuries after mine abandonment, it is necessary to apply multidisciplinary methods to determine the potential risk in a determinate area. These multidisciplinary methods must include molecular and elemental analysis and finally all information must be studied statistically. This methodology was used in the case of coal mining acid drainage from the Tubarao River (Santa Catarina, Brazil). During molecular analysis, Raman Spectroscopy, electron bean, and X-ray diffraction (XRD) have been proven very useful for the study of minerals present in sediment rivers near this CMAD. The obtained spectra allow the precise identification of the minerals as jarosite, quartz, clays, etc. The elemental analysis (Al, As, Fe, K, Na, Ba, Mg, Mn, Ti, V, Zn, Ag, Co, Li, Mo, Ni, Se, Sn, W, B, Cr, Cu, Pb and Sr) was realised by inductively coupled plasma mass spectrometry (ICP-MS). Statistical analysis (Principal Component Analysis) of these dates of concentration reveals the existence of different groups of samples with specific pollution profiles in different areas of the Tubarao River. Highlights: ► Increasing coal drainage sediments geochemical information will increase human health information in this area. ► Brazilian coal mining information will increase recuperation planning information. ► The nanominerals showed strong sorption ability to aqueous hazardous elements

  11. ROTATING DISC BIOLOGICAL TREATMENT OF ACID MINE DRAINAGE

    Pilot scale (0.5-m diameter) and prototype (2.0-m diameter) rotating biological contactors (RBC) were investigated for oxidation of ferrous Fe(II) iron contained in six heterogeneous mine waters located at three coal mining sites in Pennsylvania and West Virginia. Continuous biol...

  12. Phycomicrobial ecology of acid mine drainage in the Piedmont of Virginia

    Krishnaswamy, R.; Hanger, R.A. [George Washington Univ., Washington, DC (United States). Dept. of Geology

    1998-12-31

    Acid mine drainage encompasses 18 km{sup 2} of Louisa County, Virginia. Heavy metal laden acidic leachate flows from abandoned mines along the Piedmont`s Gold-Pyrite Belt. The oxidation of pyrite, sphalerite, chalcopyrite and other sulfide minerals that are disseminated throughout the mine tailings release H{sub 2}SO{sub 4}, Fe, Cu, Zn, Ni, Cd, As, Pb and other heavy metals into the Contrary Creek watershed and beyond, into Lake Anna. Downstream of these abandoned pyrite mines, high levels of acidity and heavy metals have made this a severely stressed environment incapable of supporting a healthy creek ecosystem. In an effort to assess in-situ, bioaccumulatory remediation of acid mine drainage by phycomicrobial mats, surveys have been conducted for 11 months in Contrary Creek; several extremophiles that are tolerant of acid mine systems have been found. Twelve to thirteen genera of algae and a few cocci and bacilli have been identified in surface waters. Predominant genera include Ulothrix, Pinnularia and Oscillatoria. Preliminary results demonstrate that the phycomicrobial communities found in this acid mine system maintain density and species diversity independent of pH and heavy metal fluctuations. These extremophiles also demonstrate high potential for heavy metal sorption. Phycomicrobial mats bioaccumulate 60--70% more heavy metals than concentrations found in surface waters and the creek. To date, remediatory attempts to restore Contrary Creek have not been successful. Results suggest that the extremophile ecology found in this system will facilitate the remediation process of other, similar acid mine affected ecosystems.

  13. Diatoms as biomonitors in two temporary streams affected by acid drainage from disused mines

    Diatoms are increasingly used as biomonitors of water quality in Australia, partly as an extension of the AUSRIVAS concept and partly through the increasing emphasis on biological/ecological monitoring of stream health that is acknowledged in the Australian and New Zealand water quality guidelines (ANZECC and ARMCANZ, 2000). This work brings together the findings of three studies relating diatom populations to the water chemistry of two temporary streams affected by acid drainage. In the three studies reported, changes in the benthic diatom flora have been successfully used to: show the toxic effects of acid drainage from two mine sites; differentiate between nutrient and acid drainage pollution in a stream system affected by more than one pollutant and provide independent corroboration of the AQUARISK ecological risk assessment code

  14. Chemical evolution of coal mine drainage in a non-acid producing environment, Wasatch Plateau, Utah, USA

    Mayo, A. L.; Petersen, E. C.; Kravits, C.

    2000-09-01

    The causes and problems of coal mine drainage, particularly acid mine drainage, in the Eastern and Interior Coal Provinces of the United States are well documented. West of the Mississippi River, where coal mines account for about 45% of total US coal production and where acid mine drainage is rare, the chemical evolution of coal mine drainage is less well documented and understood. In this investigation, we have used solute and isotopic compositions of non-evolved inflow groundwater and evolved mine discharge water to quantify the chemical evolution of mine discharge water in a western underground coal mine. Water enters the mine from fractures and roof bolt holes, which intercept groundwater in the overlying rock. Carbon-14, and 3H data indicate that these waters recharged between 12,000 and 19,500 years ago. The TDS and solute compositions of roof drip waters are spatially zoned and TDS concentrations range from about 300 to 550 mg l -1. After the water encounters minerals and other substances in the mine, the chemical differences between various mine regions become more pronounced and the TDS of mine drainage water increases to about 850 mg l -1. The TDS of mine drainage is related to water-rock ratios. Mine drainage issuing from the older mined areas, where water-rock ratios are low, has the greatest TDS. Geochemical and isotopic mass balance calculations were performed to quantify chemical reactions in the mine, and to identify sources contributing to the TDS of mine drainage. Chemical reaction pathways evaluated include pyrite oxidation, dissolution of native and rock dust gypsum, dissolution of calcite and dolomite, precipitation of calcite, ion exchange, precipitation of iron hydroxide, and organic decomposition of mining machine emulsion fluid. Solute and isotopic mass transfer reaction calculations demonstrate that the oxidation of pyrite triggers a series of cascading in-mine chemical reactions that are the primary cause of the elevated TDS of mine

  15. Geochemical study of acid mine drainage of the Big Lick Tunnel area, Williamstown, PA

    Acid mine drainage in the anthracite region of Pennsylvania continues to be a significant environmental problem. This study examines the acid mine outflow from the Big Lick Tunnel, north of Williamstown, Dauphin County, Pennsylvania. The tunnel drains abandoned mines on the north side of the Big Lick Mountain. Mining ceased in the area circa 1940, and the tunnel has been in operation since that time. The water, soil and stream bed sediment geochemistry has been studied to determine their changes in chemistry over distance. The pH, TDS and metal concentrations were the primary focus. Metal concentrations were determined using an ICP unit. Data indicates the pH of the outflow to range between 6.7 and 7.3 Fe and Mn concentrations are as high as 9.7 ppb. Extensive metal precipitation (''yellow boy'') occurs within the tunnel and for several hundred meters from the mouth of the tunnel. The combination of near neutral pH and high metal concentration suggest that the drainage is in contact with highly alkaline materials prior to discharge from the tunnel. The geology of the area does not suggest bedrock as the possible source of alkaline material. One hypothesis is that the acidic water is reacting with the concrete tunnel and being neutralized. Data also suggests that the Fe precipitates much quicker than the Mn, resulting in a zonation between Fe-rich and Mn-rich sediments along the length of the drainage

  16. Effects of acid mine drainage on southwestern Pennsylvania stream

    Moon, T.C.; Lucostic, C.M.

    1979-01-01

    Physicochemical parameters and benthic macroinvertebrate community structure were studied in a small valley stream in southwestern Pennsylvania, where the pH value below a coal mine effluent discharge was 5.8-7.0. The major factor affecting the benthic community seemed to be ferric hydroxide. Certain taxa were abundant at station sites above the mine discharge, while only those taxa tolerant of polluted conditions, such as Chironomidae and Tubifex, were prevalent at the downstream station sites. An analysis of benthic populations demonstrated environmental stress within the aquatic ecosystem.

  17. Metal release from fly ash upon leaching with sulfuric acid or acid mine drainage

    Generation of electricity by coal-fired power plants produces large quantities of bottom ash and fly ash. New power plants commonly use fluidized bed combustion (FBC) boilers, which create ashes with high neutralization potential (NP). These ashes, due to their alkaline nature, are often used in surface mine reclamation to neutralize acidity and reduce hydraulic conductivity of disturbed overburdens. Conventional fly ashes from older power plants exhibit a range of pH and NP, with some ashes having neutral or acidic pH and low NP values, and may not be good candidates for supplying alkalinity in reclamation projects. In this study, the authors used two acidic solutions to leach a low NP fly ash (LNP ash) and two FBC ashes (FBC1 and FBC2). After passing 78 pore volumes of sulfuric acid and 129 pore volumes of acid mine drainage (AMD) through these ash materials several trace elements were found at high levels in the leachates. LNP fly ash leachates had high arsenic and selenium concentrations with sulfuric acid leaching, but showed low arsenic and selenium concentrations after leaching with AMD. Leaching with AMD caused the iron and aluminum inherent in AMD to complex these elements and make them unavailable for leaching. Lead, cadmium, and barium concentrations in fly ash leachates were not high enough to cause water pollution problems with either leaching solution. For both leaching solutions, manganese was released from LNP ash at a constant level, FBC1 ash did not release manganese, and FBC2 ash released manganese only after the NP had been exhausted by >60 pore volumes of leaching

  18. The use of constructed wetlands in the treatment of acid mine drainage

    US government regulations require that all effluents from industrial operations, including mining, meet certain water quality standards. Constructed wetlands have proven to be useful in helping to attain those standards. Application of this biotechnology to mine water drainage can reduce water treatment costs and improve water quality in streams and rivers adversely affected by acidic mine water drainage from abandoned mines. Over 400 constructed wetland water treatment systems have been built on mined lands largely as a result of research by the US Bureau of Mines. Wetlands are passive biological treatment systems that are relatively inexpensive to construct and require minimal maintenance. Chemical treatment costs are reduced sufficiently to repay the cost of construction in less than a year. The mine waste water is typically treated in a series of excavated ponds that resemble small marsh areas. The ponds are engineered to facilitate bacterial oxidation of iron. Ideally, the water then flows through a composted organic substrate supporting a population of sulphate-reducing bacteria which raises the pH. Constructed wetlands in the USA are described - their history, functions, construction methodologies, applicabilities, limitations and costs. (author). 26 refs, 2 figs

  19. Benthic Communities of Low-Order Streams Affected by Acid Mine Drainages: A Case Study from Central Europe

    Marek Svitok; Milan Novikmec; Peter Bitušík; Branislav Máša; Jozef Oboňa; Miroslav Očadlík; Eva Michalková

    2014-01-01

    Only little attention has been paid to the impact of acid mine drainages (AMD) on aquatic ecosystems in Central Europe. In this study, we investigate the physico-chemical properties of low-order streams and the response of benthic invertebrates to AMD pollution in the Banská Štiavnica mining region (Slovakia). The studied streams showed typical signs of mine drainage pollution: higher conductivity, elevated iron, aluminum, zinc and copper loads and accumulations of ferric precipitates. Elect...

  20. Uniform particles formed by hydrolysis of acid mine drainage with urea

    Šubrt, Jan; Michalková, E.; Boháček, Jaroslav; Lukáč, Jozef; Gánovská, Z.; Máša, B.

    2011-01-01

    Roč. 106, 1-2 (2011), s. 12-18. ISSN 0304-386X R&D Projects: GA MŠk LC523; GA MŠk(CZ) MEB0810136 Institutional research plan: CEZ:AV0Z40320502 Keywords : acid mine drainage * urea hydrolysis * morphology * particles * surface area Subject RIV: CA - Inorganic Chemistry Impact factor: 2.027, year: 2011

  1. Sediment-water interaction in a water reservoir affected by acid mine drainage : experimental and modeling

    Torres Sánchez, Ester

    2013-01-01

    The discharge of acid mine drainage into a water reservoir may seriously affect the water quality. In this setting, sediment is commonly thought to act as a sink for pollutants. However, redox oscillations in the bottom water promoted by stratification-turnover events may significantly alter the metal cycling. A new sequential extraction procedure has been developed to study the metal partitioning in the sediment. The new scheme for iron, sulfur and organic carbon rich sediments was evaluated...

  2. Mineralogy and acid-mine drainage of La Creusaz uranium prospect, Switzerland

    The hydrothermal uranium deposit La Creusaz is located in the Aiguilles Rouges massif in the Western Swiss Alps. Alpine metamorphism and Quaternary erosion and alteration affected this late Variscan deposit. Numerous neoformed U(VI) sulfates, comprising several new mineral species, result of acid mine drainage process. A study of U-migration in soil and plants suggest that the grass species Agrostis schraderiana is a bioaccumulator ideally suited for the decontamination of U-polluted sites in alpine regions. (author)

  3. Macroinvertebrate community response to acid mine drainage in rivers of the High Andes (Bolivia)

    Several High Andes Rivers are characterized by inorganic water pollution known as acid mine drainage (AMD). The aim of this study was to assess the relationship between metal concentrations in the sediments and the macroinvertebrate communities in two river basins affected by AMD. In general, the taxon diversity of the macroinvertebrate community at the family level was low. The concentrations of Cd, Cu, Zn, Pb and Ni at mining sites were higher than at unpolluted sites. The pH of the water was alkaline (7.0-8.5) in unpolluted sites, whereas it dropped to very low values (<3) at mining sites. Redundancy Analysis (RDA) showed that pH was the best predictor of macroinvertebrate community richness. The number of macroinvertebrate families decreased gradually with increasing acidity, both in pools and riffles, though it is suggested that riffle communities were more affected because they are in closer contact with the acid water. - Community response to AMD

  4. Macroinvertebrate community response to acid mine drainage in rivers of the High Andes (Bolivia)

    Van Damme, Paul Andre [Asociacion Faunagua, Cochabamba (Bolivia, Plurinational State of); Centre of Limnology and Aquatic Resources, University of San Simon, Casilla 5263, Cochabamba (Bolivia, Plurinational State of); Hamel, Caroli; Ayala, Alfredo [Centre of Limnology and Aquatic Resources, University of San Simon, Casilla 5263, Cochabamba (Bolivia, Plurinational State of); Bervoets, Lieven [Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)], E-mail: lieven.bervoets@ua.ac.be

    2008-12-15

    Several High Andes Rivers are characterized by inorganic water pollution known as acid mine drainage (AMD). The aim of this study was to assess the relationship between metal concentrations in the sediments and the macroinvertebrate communities in two river basins affected by AMD. In general, the taxon diversity of the macroinvertebrate community at the family level was low. The concentrations of Cd, Cu, Zn, Pb and Ni at mining sites were higher than at unpolluted sites. The pH of the water was alkaline (7.0-8.5) in unpolluted sites, whereas it dropped to very low values (<3) at mining sites. Redundancy Analysis (RDA) showed that pH was the best predictor of macroinvertebrate community richness. The number of macroinvertebrate families decreased gradually with increasing acidity, both in pools and riffles, though it is suggested that riffle communities were more affected because they are in closer contact with the acid water. - Community response to AMD.

  5. Acid mine drainage treatment using by-products from quicklime manufacturing as neutralization chemicals.

    Tolonen, Emma-Tuulia; Sarpola, Arja; Hu, Tao; Rämö, Jaakko; Lassi, Ulla

    2014-12-01

    The aim of this research was to investigate whether by-products from quicklime manufacturing could be used instead of commercial quicklime (CaO) or hydrated lime (Ca(OH)2), which are traditionally used as neutralization chemicals in acid mine drainage treatment. Four by-products were studied and the results were compared with quicklime and hydrated lime. The studied by-products were partly burnt lime stored outdoors, partly burnt lime stored in a silo, kiln dust and a mixture of partly burnt lime stored outdoors and dolomite. Present application options for these by-products are limited and they are largely considered waste. Chemical precipitation experiments were performed with the jar test. All the studied by-products removed over 99% of Al, As, Cd, Co, Cu, Fe, Mn, Ni, Zn and approximately 60% of sulphate from acid mine drainage. However, the neutralization capacity of the by-products and thus the amount of by-product needed as well as the amount of sludge produced varied. The results indicated that two out of the four studied by-products could be used as an alternative to quicklime or hydrated lime for acid mine drainage treatment. PMID:25193795

  6. Microbial stratification in low pH oxic and suboxic macroscopic growths along an acid mine drainage

    Méndez-García, Celia; Mesa, Victoria; Sprenger, Richard Remko;

    2014-01-01

    Macroscopic growths at geographically separated acid mine drainages (AMDs) exhibit distinct populations. Yet, local heterogeneities are poorly understood. To gain novel mechanistic insights into this, we used OMICs tools to profile microbial populations coexisting in a single pyrite gallery AMD (...

  7. Behaviour of U-Isotopes in an Estuary Affected by Acid Mine Drainage and Industrial Releases

    Tinto and Odiel rivers (SW of Spain) is an ecosystem of great interest that is seriously affected by acid mine drainage (AMD) from long-term mining activities (pH < 3). Additionally, a large industrial complex is located in the surroundings of this estuary and Huelva town, which includes two phosphate rock processing plants that produce about 3 millions of tons per year of a byproduct called phosphogypsum (PG) containing high U-series radionuclides concentrations. For these reasons, the estuary of Huelva is one of the most heavy metals and radionuclides polluted estuarine systems in Europe with extremely low pH.

  8. Iron-mineral accretion from acid mine drainage and its application in passive treatment

    Florence, K.; Sapsford, D.J.; Johnson, D.B.; Kay, C. M.; Wolkersdorfer, C.

    2016-01-01

    ABSTRACT This study demonstrates substantial removal of iron (Fe) from acid mine drainage (pH ≈3) in a passive vertical flow reactor (VFR) with an equivalent footprint of 154 m2 per L/s mine water and residence times of >23 h. Average Fe removal rate was 67% with a high of 85% over the 10-month trial. The fraction of Fe passing a 0.22 µm filter (referred to here as Fe-filt) was seen to be removed in the VFR even when Fe(II) was absent, indicating that the contribution of microbial Fe(II) oxid...

  9. Acid mine drainage and stream recovery: Effects of restoration on water quality, macroinvertebrates, and fish

    Williams K.M.; Turner A.M.

    2015-01-01

    Acid mine drainage (AMD) is a prominent threat to water quality in many of the world’s mining districts as it can severely degrade both the biological community and physical habitat of receiving streams. There are relatively few long-term studies investigating the ability of stream ecosystems to recover from AMD. Here we assess watershed scale recovery of a cold-water stream from pollution by AMD using a 1967 survey of the biological and chemical properties of the stream as a pre-restoration ...

  10. Oxidative Precipitation of Manganese from Acid Mine Drainage by Potassium Permanganate

    Regeane M. Freitas; Perilli, Thomaz A. G.; Ladeira, Ana Claudia Q.

    2013-01-01

    Although oxidative precipitation by potassium permanganate is a widely recognised process for manganese removal, research dealing with highly contaminated acid mine drainage (AMD) has yet to be performed. The present study investigated the efficiency of KMnO4 in removing manganese from AMD effluents. Samples of AMD that originated from inactive uranium mine in Brazil were chemically characterised and treated by KMnO4 at pH 3.0, 5.0, and 7.0. Analyses by Raman spectroscopy and geochemical mode...

  11. Interaction of trace elements in acid mine drainage solution with humic acid.

    Suteerapataranon, Siripat; Bouby, Muriel; Geckeis, Horst; Fanghänel, Thomas; Grudpan, Kate

    2006-06-01

    The release of metal ions from a coal mining tailing area, Lamphun, Northern Thailand, is studied by leaching tests. Considerable amounts of Mn, Fe, Al, Ni and Co are dissolved in both simulated rain water (pH 4) and 10 mg L(-1) humic acid (HA) solution (Aldrich humic acid, pH 7). Due to the presence of oxidizing pyrite and sulfide minerals, the pH in both leachates decreases down to approximately 3 combined with high sulfate concentrations typical to acid mine drainage (AMD) water composition. Interaction of the acidic leachates upon mixing with ground- and surface water containing natural organic matter is simulated by subsequent dilution (1:100; 1:200; 1:300; 1:500) with a 10 mg L(-1) HA solution (ionic strength: 10(-3) mol L(-1)). Combining asymmetric flow field-flow fractionation (AsFlFFF) with UV/Vis and ICP-MS detection allows for the investigation of metal ion interaction with HA colloid and colloid size evolution. Formation of colloid aggregates is observed by filtration and AsFlFFF depending on the degree of the dilution. While the average HA size is initially found to be 2 nm, metal-HA complexes are always found to be larger. Such observation is attributed to a metal induced HA agglomeration, which is found even at low coverage of HA functional groups with metal ions. Increasing the metal ion to HA ratio, the HA bound metal ions and the HA entities are growing in size from 450 nm. At high metal ion to HA ratios, precipitation of FeOOH phases and HA agglomeration due to colloid charge neutralization by complete saturation of HA complexing sites are responsible for the fact that most of Fe and Al precipitate and are found in a size fraction >450 nm. In the more diluted solutions, HA is more relevant as a carrier for metal ion mobilization. PMID:16631855

  12. Water Quality Based Design Guidelines for Successive Alkalinity-Producing Systems Used in the Treatment of Acidic Mine Drainage

    Jage, Christopher Raymond

    2000-01-01

    Water Quality Based Design Guidelines for Successive Alkalinity-Producing Systems Used in the Treatment of Acidic Mine Drainage by Christopher Raymond Jage Carl Zipper, Chair Crop and Soil Environmental Sciences (ABSTRACT) Successive Alkalinity-Producing Systems (SAPS) have proven to be a viable alternative to chemical treatment for renovating acidic mine drainage (AMD). The lack of water quality based design guidelines, however, is believed to be a cause of the variability...

  13. A continuous pilot-scale system using coal-mine drainage sludge to treat acid mine drainage contaminated with high concentrations of Pb, Zn, and other heavy metals

    Highlights: ► Coal mine drainage sludge can effectively neutralize and treat the acidic drainage for a long time. ► We suggest that the continuous pilot system having CMDS can not only high removal efficiencies, but also high total rates for all heavy metals. ► The pilot system can have a much higher Zn(II) loading rate than other referenced systems such as wetland coupled with algal mat and anoxic limestone drain. - Abstract: A series of pilot-scale tests were conducted with a continuous system composed of a stirring tank reactor, settling tank, and sand filter. In order to treat acidic drainage from a Pb–Zn mine containing high levels of heavy metals, the potential use of coal-mine drainage sludge (CMDS) was examined. The pilot-scale tests showed that CMDS could effectively neutralize the acidic drainage due to its high alkalinity production. A previous study revealed that calcite and goethite contained in CMDS contributed to dissolutive coprecipitation and complexation with heavy metals. The continuous system not only has high removal efficiencies (97.2–99.8%), but also large total rate constants (Ktotal, 0.21–10.18 h−1) for all heavy metals. More specifically, the pilot system has a much higher Zn(II) loading rate (45.3 g m−3 day−1) than other reference systems, such as aerobic wetland coupled with algal mats and anoxic limestone drains. The optimum conditions were found to be a CMDS loading of 280 g L−1 and a flow rate of 8 L day−1, and the necessary quantity of CMDS was 91.3 g L−1 day−1, as the replacement cycle of CMDS was determined to be 70 days.

  14. Bioremediation of acid mine drainage: an introduction to the Wheal Jane wetlands project.

    Whitehead, P G; Prior, H

    2005-02-01

    Acid mine drainage (AMD) is a widespread environmental problem associated with both working and abandoned mining operations. As part of an overall strategy to determine a long-term treatment option for AMD, a pilot passive treatment plant was constructed in 1994 at Wheal Jane Mine in Cornwall, UK. The plant consists of three separate systems; each containing aerobic reed beds, anaerobic cell and rock filters, and represents the largest European experimental facility of its kind. The systems only differ by the type of pre-treatment utilised to increase the pH of the influent minewater (pHsystems. The project has led to data, knowledge, models and design criteria for the future design, planning and sustainable management of passive treatment systems. A multidisciplinary team of scientists and managers from the U.K. universities, the Environment Agency and the Mining Industry has been put together to obtain the maximum advantage from the excellent facilities facility at Wheal Jane. PMID:15680623

  15. Plan for injection of coal combustion byproducts into the Omega Mine for the reduction of acid mine drainage

    The Omega Mine Complex is located outside of Morgantown, West Virginia. The mine is in the Upper Freeport Coal, an acid-producing coal seam. The coal was mined in a manner that has resulted in acid mine drainage (AMD) discharges at multiple points. During the 1990's, the West Virginia Division of Environmental Protection (WVDEP) assumed responsibility for operating a collection and treatment system for the AMD. Collection and treatment costs are approximately $300,000 per year. Injecting grout into the mine workings to reduce AMD (and thus reducing treatment costs) is proposed. The procedure involves injecting grout mixes composed primarily of coal combustion byproducts (CCB's) and water, with a small quantity of cement. The intention of the injection program is to fill the mine voids in the north lobe of the Omega Mine (an area where most of the acidity is believed to be generated) with the grout, thus reducing the contact of air and water with potentially acidic material. The grout mix design consists of an approximate 1:1 ratio of fly ash to byproducts from fluidized bed combustion. Approximately 100 gallons of water per cubic yard of grout is used to achieve flowability. Observation of the mine workings via subsurface borings and downhole video camera confirmed that first-mined areas were generally open while second-mined areas were generally partially collapsed. The injection program was developed to account for this by utilizing closer injection hole spacing in second-mined areas. Construction began in January 1998, with grout injection expected to commence in mid-April 1998

  16. CCB-based encapsulation of pyrite for remediation of acid mine drainage.

    Bulusu, Sowmya; Aydilek, Ahmet H; Rustagi, Neha

    2007-05-17

    Acid mine drainage (AMD) from abandoned coal mines continues to be one of the most significant environmental problems. Remediation of AMD requires an addition of lime source to decrease the acidity, and grouting the entire mine and encapsulating the pyrite by calcium-rich additives is often employed. Utilization of alkaline coal combustion by-products (CCBs) has gained acceptance in such remediation applications because of their cost-effectiveness. A study was conducted to investigate the effectiveness of CCBs to abate acid mine drainage by encapsulation of pyrite. Geomechanical, hydraulic, and environmental tests were performed on grouts prepared with various ratios of CCBs as well as an alternative free lime source, lime kiln dust (LKD). The results indicated that the mechanical properties of grouts were dependent on their free lime contents. Hydraulic conductivities of pyrite-grout columns were relatively high due to the coating of the pyrite rock with the grout rather than the filling of all of the void spaces, as commonly experienced in field applications. The leaching tests indicated that the presence of high amounts of lime in a grout is not solely sufficient to improve the quality of AMD, since the rate of dissolution of a high lime content grout may be slow due to its rapid hardening. Therefore, it is recommended that grouts be selected with consideration of their hardening capacities, as well as the percentage of lime content present in the mixture. PMID:17303328

  17. Fe biogeochemistry in reclaimed acid mine drainage precipitates—Implications for phytoremediation

    At a 50-year-old coal mine drainage barrens in central Pennsylvania, USA, we evaluated the biogeochemistry of acidic, Fe(III)oxy(hydr)oxide precipitates in reclaimed plots and compared them to untreated precipitates in control areas. Reclaimed plots supported successional vegetation that became established after a one-time compost and lime treatment in 2006, while control plots supported biological crusts. Precipitates were sampled from moist yet unsaturated surface layers in an area with lateral subsurface flow of mine drainage above a fragipan. Fe(II) concentrations were three- to five-fold higher in reclaimed than control precipitates. Organically bound Fe and amorphous iron oxides, as fractions of total Fe, were also higher in reclaimed than control precipitates. Estimates of Fe-reducing and Fe-oxidizing bacteria were four- to tenfold higher in root-adherent than both types of control precipitates. By scaling up measurements from experimental plots, total Fe losses during the 5-yr following reclamation were estimated at 45 t Fe ha−1 yr−1. -- Highlights: • Reclaimed AMD precipitates contained more Fe(II) and organically bound Fe than control precipitates. • Fe(II) concentrations were positively correlated with organic C and Fe-reducing microbes. • Vegetative reclamation of AMD precipitates can mobilize Fe in hydrologically sensitive areas. -- Rooting zones of reclaimed acid mine drainage precipitates had higher Fe(II) and organically bound Fe than precipitates at lower depths and in unreclaimed control areas

  18. Policy for metal leaching and acid rock drainage at mine sites in British Columbia

    One of the major environmental issues facing the provincial government of British Columbia is the prevention of environmental impacts from metal leaching and acid rock drainage (ML/ARD). The government's major challenge in regulating ML/ARD is to ensure that all mines are planned and operated in a manner that allows for effective problem detection and mitigation, and that the mines emphasize problem prevention at the outset. This paper reviews the legislated requirements regarding ML/ARD prevention and lists guiding principles for the regulation of ML/ARD in the province. Some of the measures to predict and to mitigate ML/ARD include underwater storage of problematic materials, engineered covers, blending of wastes and drainage collection and treatment. Requirements applicable to construction materials, backfill, geotechnical and hydrological considerations, and security of funds for ML/ARD measures are also discussed

  19. Application of nanofiltration to the treatment of acid mine drainage waters

    This study investigated the separation of uranium and other elements in high concentrations from acid mine waters at Caldas Uranium Mining, in the southeast of Brazil, using nanofiltration membranes. Nanofiltrarion is widely used in water treatment due to the lower energy requirements and higher yields than reverse osmosis. Separation characteristics are dependent on both the molecular size and charge of the dissolved species in the feed solution as well as membrane properties. In this investigation the potential of nanofiltration to removed dissolved species like uranium from acid mine water drainage was measured. Two composite aromatic polyamide commercially membranes of FilmTec/Dow were tested and it found that uranium rejections of greater than 90% and also showed potential for the separation of aluminum and manganese. (author)

  20. Roles of Benthic Algae in the Structure, Function, and Assessment of Stream Ecosystems Affected by Acid Mine Drainage

    Tens of thousands of stream kilometers around the world are degraded by a legacy of environmental impacts and acid mine drainage (AMD) caused by abandoned underground and surface mines, piles of discarded coal wastes, and tailings. Increased acidity, high concentrations of metals...

  1. Acid mine drainage arising from gold mining activity in Johannesburg, South Africa and environs

    Ground water within the mining district is heavily contaminated and acidified. - The Witwatersrand region of South Africa is famous for its gold production and a major conurbation, centred on Johannesburg, has developed as a result of mining activity. A study was undertaken of surface and ground water in a drainage system in this area. Soils were also analysed from a site within the mining district. This study revealed that the ground water within the mining district is heavily contaminated and acidified as a result of oxidation of pyrite (FeS2) contained within mine tailings dumps, and has elevated concentrations of heavy metals. Where the water table is close to surface, the upper 20 cm of soil profiles are severely contaminated by heavy metals due to capillary rise and evaporation of the ground water. The polluted ground water is discharging into streams in the area and contributes up to 20% of stream discharge, causing a lowering of pH of the stream water. Much of the metal load is precipitated in the stream: Fe and Mn precipitate as a consequence of oxidation, while other heavy metals are being removed by co-precipitation. The oxidation of iron has created a redox buffer which controls the pH of the stream water. The rate of oxidation and of dilution is slow and the deleterious effect of the addition of contaminated water persists for more than 10 km beyond the source

  2. Electrochemical treatment of acidic aqueous ferrous sulfate and copper sulfate as models for acid mine drainage.

    Bunce, N J; Chartrand, M; Keech, P

    2001-12-01

    Acid mine drainage (AMD) is a serious environmental problem in the mining industry. The present work describes electrolytic reduction of solutions of synthetic AMD, comprising FeSO4/H2SO4 and CuSO4/H2SO4, in flow-through cells whose anode and cathode compartments were separated using ion exchange membranes. In the case of FeSO4/H2SO4 at constant flow rate, the pH of the effluent from the catholyte increased progressively with current at a variety of cathodes, due to electrolytic reduction of H+ ions to elemental hydrogen. Near-quantitative removal of iron was achieved by sparging air into the catholyte effluent, thereby precipitating iron outside the electrochemical cell, and avoiding fouling of the electrodes. The anode reaction was the oxidation of water to O2, a proton-releasing process. Using cation exchange membranes and sodium sulfate as the supporting electrolyte in the anode compartment, the efficiency of the process was compromised at high currents by transport of H+ competitively with Na+ from the anode to the cathode compartments. Higher efficiencies were obtained when anion exchange membranes were used, and in this case no additional supporting electrolyte other than dilute H2SO4 was needed, the net reaction being the electrochemically driven transfer of the elements of H2SO4 from the cathode to the anode compartments. Current efficiencies approximately 50% were achieved, the loss of efficiency being accounted for by ohmic heating of the solutions. In the case of CuSO4/H2SO4 and anion exchange membranes at high currents, reduction of Cu2+ and H+ ions and transport of SO4(2-) ions out of the catholyte caused unacceptably high potentials to be generated. PMID:11763043

  3. Flue gas desulfurization by-product weathering by acidic mine drainage

    The authors examined the suitability using a flue gas desulfurization grout (FGDG) for the attenuation and abatement of acidic mine drainage (AMD). The FGDG used was a mixture of fly ash (FA) and filter cake (FC) with a FA/FC ratio of 1:1 to improve handling. Five percent of lime (CaO) was added to improve strength development and allow the use of this FGDG as a hydrologic seal for underground mines. Acidic mine drainage solutions collect from wells located within mine voids were reacted with samples of FGDG for up to 168 d, to evaluate the potential for grout dissolution subsequent to subterranean implacement. Shortly upon reaction with AMD, FGDG released a number of ions into solution (As, B, Ca, K, Na, Se, SO4), a concomitant with a rapid increase in solution pH (8.5), causing decreases in the solubility of most cations (Al, Fe, Mn, Zn). Significant increases in dissolved As and B concentrations were noted. Both elements were present in solution at levels below respective regulatory limits for drinking water. Of the original quantities of As and B present in FGDG, 1.3 and 45.6%, respectively, were released to solution over a 168-d reaction period. Concomitant with changes in solution composition, reaction of FGDG with AMD resulted in a loss of ettringite and hannebachgite and a growth of gypsum. Additional changes in mineralogy were observed as FGDG equilibrated with AMD solutions. From these reactions, the long-term stability of FGDG in underground acidic mine environments is questionable and warrants study in situ

  4. Biochemical process for the removal of uranium from acid mine drainages

    A biochemical process has been assessed with a view to removing heavy metals from acid mine drainages in which the metal cation removed is accumulated in situ as insoluble metal phosphate on the surface of Citrobacter N 14 cells (Roig et al., 1995). The localized presence of inorganic phosphate (Pi) is brought about via the hydrolysis of a ''donor'' organic phosphate added to the solution of metals with precipitation as MHPO4 bound to the cells. The present work explores the potential of immobilized Citrobacter biomass for the recovery of uranium from the acid drainage waters of the ''Faith'' mine exploited by ENUSA (Ciudad Rodrigo, Salamanca). A physicochemical characterization of the acid waste-water from ENUSA was carried out and flow injection analysis methods for the determination of uranium and Pi in such water were developed and improved. The efficiencies of chemical precipitation (by the addition of Pi to the acid water) with regard to bioinsolubilization (supplementing the water with an organic phosphate that is (later) hydrolysed to Pi) were investigated and compared. Additionally, the efficiency of chemical and biochemical precipitation as phosphates of uranium present in ENUSA acid drainage water were assessed. Furthermore, the relative importance of chemical precipitation (by the addition of Pi to the acid water) with regard to bioinsolubilization (supplementing the water with an organic phosphate that is (later) hydrolysed to Pi plus alcohol) was established. To do so, a series of mass balances for chemical precipitation and for bioinsolubilization of the metal phosphate was performed. Once the efficiency of the bioprocess as regards the removal of uranium when glycerol-2-phosphate is used as a substrate had been determined, a major question was forthcoming: the search for an efficient and much more economical substrate for the process. In this sense, sodium tripolyphosphate, one of the main components of many formulations of commercial detergents

  5. Interaction of acid mine drainage with waters and sediments of West Squaw Creek in the West Shasta Mining District, California

    Filipek, L.H.; Kirk, Nordstrom D.; Ficklin, W.H.

    1987-01-01

    Acid mine drainage has acidified large volumes of water and added high concentrations of dissolved heavy metals to West Squaw Creek, a California stream draining igneous rocks of low acid-neutralizing capacity. During mixing of the acid sulfate stream waters in the South Fork of West Squaw Creek with an almost equal volume of dilute uncontaminated water, Cu, Zn, Mn, and Al remained in solution rather than precipitating or adsorbing on solid phases. Changes in the concentration of these generally conservative metals could be used to determine relative flow volumes of acid tributaries and the main stream. An amorphous orange precipitate (probably ferric hydroxides or a mixture of ferric hydroxides and jarosite) was ubiquitous in the acid stream beds and was intimately associated with algae at the most acid sites. Relative sorption of cations decreased with decreasing water pH. However, arsenic was almost completely scavenged from solution within a short distance from the sulfide sources.

  6. Acid mine drainage mitigation using bulk blended fly ash/coal refuse mixtures: Column study results

    Many Appalachian coal refuse materials contain significant amounts of pyritic-S and are likely to produce acid mine drainage (AMD). A column technique was designed and implemented to evaluate the effects of various AMD mitigation treatments including fly ash, topsoil, lime, and rock-P. Two types of fly ash were tested, one at four rates of application, the other at two rates. Conventional lime plus topsoil, lime without topsoil, topsoil only, topsoil with fly ash, rock-P, rock-P plus topsoil, and rock-P plus fly ash were also evaluated and compared with pure refuse controls. The drainage from the unamended columns rapidly dropped to pH 2 with very high levels of Fe and Mn. Alkaline fly ash dramatically reduced drainage Fe concentrations as well as Mn when compared with untreated refuse. The rock-P treatment also improved drainage but eventually lost its mitigation capability. Leachate B concentrations were initially high for some of the ash columns, but decreased over time, while the unamended refuse B levels increased with time. Combined treatments of phosphate/ash, ash/topsoil, and pure refuse with topsoil were intermediate between the alkaline ash/lime treatments and unamended refuse in drainage quality. With further analysis, fly ash may prove to be a viable alternative to conventional topsoiling/lime treatments to control AMD if adequate alkalinity is present in the ash/refuse mixture. If fly ash alkalinity is inadequate to balance potential acidity, accelerated leaching of ash bound metals may occur. Therefore, the uncontrolled disposal of fly ash within coal refuse disposal facilities should be discouraged unless acid/base balance concerns are met

  7. Study of waste rock piles producing acid drainage in the Brazilian first uranium mine

    Oliveira, Alexandre P. de; Rey-Silva, Daniela V.F.M.; Barreto, Rodrigo P., E-mail: apolivei@cnen.gov.b [Brazilian National Commission for Nuclear Energy (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Pocos de Caldas Lab.; Souza-Santos, Marcio L. de, E-mail: dss@fem.unicamp.b [University of Campinas (UNICAMP), SP (Brazil). Faculty of Mechanical Engineering; Veronesi, Luciano da S., E-mail: lsv61@hotmail.co [Catholic University of Pocos de Caldas (PUC-PCaldas), MG (Brazil). Civil Engineering Dept.

    2009-07-01

    The Uranium Mine and Milling Facility located in the Pocos de Caldas Plateau stopped operating since mid-1990's and remediation actions for the mine areas are going to take place in the near future. However, environmental concerns should be addressed such as acid mine drainage (AMD) in the waste rock piles (WRPs), pit mine, and tailing dam, all driven by pyrite oxidation reactions. The AMD process leaches both heavy metals and radionuclides pollutants through the soil. This work shows the methodology applied for the determination of chemical species leaching from WRP4 as well the generation of acid waters. An experimental setup has been assembled to determine the acidity of water in contact with samples of material from the WRP4. Results are presented along a list of chemical species found in the remaining water. That is followed by discussions regarding its pH and chemical composition measured during the experiments. It has been observed that not only water and available oxygen are significant to the pyrite oxidation reaction, but also bacterial activity. This last effect should be addressed in the near future. Moreover, various important aspects regarding the experimental setup were noticed and are addressed as propositions for the continuation of the present work. (author)

  8. Study of waste rock piles producing acid drainage in the Brazilian first uranium mine

    The Uranium Mine and Milling Facility located in the Pocos de Caldas Plateau stopped operating since mid-1990's and remediation actions for the mine areas are going to take place in the near future. However, environmental concerns should be addressed such as acid mine drainage (AMD) in the waste rock piles (WRPs), pit mine, and tailing dam, all driven by pyrite oxidation reactions. The AMD process leaches both heavy metals and radionuclides pollutants through the soil. This work shows the methodology applied for the determination of chemical species leaching from WRP4 as well the generation of acid waters. An experimental setup has been assembled to determine the acidity of water in contact with samples of material from the WRP4. Results are presented along a list of chemical species found in the remaining water. That is followed by discussions regarding its pH and chemical composition measured during the experiments. It has been observed that not only water and available oxygen are significant to the pyrite oxidation reaction, but also bacterial activity. This last effect should be addressed in the near future. Moreover, various important aspects regarding the experimental setup were noticed and are addressed as propositions for the continuation of the present work. (author)

  9. Sulfate reduction at low pH to remediate acid mine drainage

    Sánchez-Andrea, Irene, E-mail: irene.sanchezandrea@wur.nl [Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid (Spain); Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen (Netherlands); Sanz, Jose Luis [Departamento de Biología Molecular, Universidad Autónoma de Madrid, 28049 Madrid (Spain); Bijmans, Martijn F.M. [Wetsus, Centre of Sustainable Water Technology, P.O. Box 1113, 8900 CC Leeuwarden (Netherlands); Stams, Alfons J.M. [Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen (Netherlands); IBB – Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, 4710-057 Braga (Portugal)

    2014-03-01

    Highlights: • Acid mine drainage (AMD) is an important environmental concern. • Remediation through biological sulfate reduction and metal recovery can be applied for AMD. • Microbial community composition has a major impact on the performance of bioreactors to treat AMD. • Acidophilic SRB are strongly influenced by proton, sulfide and organic acids concentration. - Abstract: Industrial activities and the natural oxidation of metallic sulfide-ores produce sulfate-rich waters with low pH and high heavy metals content, generally termed acid mine drainage (AMD). This is of great environmental concern as some heavy metals are highly toxic. Within a number of possibilities, biological treatment applying sulfate-reducing bacteria (SRB) is an attractive option to treat AMD and to recover metals. The process produces alkalinity, neutralizing the AMD simultaneously. The sulfide that is produced reacts with the metal in solution and precipitates them as metal sulfides. Here, important factors for biotechnological application of SRB such as the inocula, the pH of the process, the substrates and the reactor design are discussed. Microbial communities of sulfidogenic reactors treating AMD which comprise fermentative-, acetogenic- and SRB as well as methanogenic archaea are reviewed.

  10. Sulfate reduction at low pH to remediate acid mine drainage

    Highlights: • Acid mine drainage (AMD) is an important environmental concern. • Remediation through biological sulfate reduction and metal recovery can be applied for AMD. • Microbial community composition has a major impact on the performance of bioreactors to treat AMD. • Acidophilic SRB are strongly influenced by proton, sulfide and organic acids concentration. - Abstract: Industrial activities and the natural oxidation of metallic sulfide-ores produce sulfate-rich waters with low pH and high heavy metals content, generally termed acid mine drainage (AMD). This is of great environmental concern as some heavy metals are highly toxic. Within a number of possibilities, biological treatment applying sulfate-reducing bacteria (SRB) is an attractive option to treat AMD and to recover metals. The process produces alkalinity, neutralizing the AMD simultaneously. The sulfide that is produced reacts with the metal in solution and precipitates them as metal sulfides. Here, important factors for biotechnological application of SRB such as the inocula, the pH of the process, the substrates and the reactor design are discussed. Microbial communities of sulfidogenic reactors treating AMD which comprise fermentative-, acetogenic- and SRB as well as methanogenic archaea are reviewed

  11. Water table lowering to improve excavation performance and to reduce acid mine drainage

    This paper analyses the water table level fluctuations using wells located adjacent to the stripping cuts at the Butia-Leste coal mine, southernmost of Brazil. Piezometers monitored the water table fluctuations. Geological mapping provided additional information aiding the interpretation of the results. A contouring software was also used as tool to aid the interpretation of the data and the results visualisation. The parameters necessary in selecting the location of the wells and pumping volumes were calculated from the data obtained in the water table lowering tests. The results were used to minimise two main problems: the generation of acid mine drainage and the reduction of the excavation performance of the fleet used in overburden removal. 7 refs., 5 figs., 3 tabs

  12. Evolution of sulfide oxidation and attenuation mechanisms controlling acid mine drainage in decommissioned low-sulfide tailings

    Parviainen, Annika

    2012-01-01

    Environmental hazards derived from mining have been a major concern worldwide in the past years. Understanding of the consequences of malpractice in waste management and the lack of aftercare is crucial to the sustainability of the future mining industry. Mineralogical and geochemical studies are key to predicting the generation of acid mine drainage (AMD) and to evaluating the stability of a tailings system at an advanced stage of weathering. Site-specific data also assist in selecting the r...

  13. Monitoring the Extent of Contamination from Acid Mine Drainage in the Iberian Pyrite Belt (SW Spain) Using Hyperspectral Imagery

    Asuncion Riaza; Andreas Müller; Veronique Carrère; Eduardo García-Meléndez; Jorge Buzzi

    2011-01-01

    Monitoring mine waste from sulfide deposits by hyperspectral remote sensing can be used to predict surface water quality by quantitatively estimating acid drainage and metal contamination on a yearly basis. In addition, analysis of the mineralogy of surface crusts rich in soluble salts can provide a record of annual humidity and temperature. In fact, temporal monitoring of salt efflorescence from mine wastes at a mine site in the Iberian Pyrite Belt (Huelva, Spain) has been achieved using hyp...

  14. Geochemical processes controlling fate and transport of arsenic in acid mine drainage (AMD) and natural systems.

    Cheng, Hefa; Hu, Yuanan; Luo, Jian; Xu, Bin; Zhao, Jianfu

    2009-06-15

    Acid mine drainage (AMD) is often accompanied with elevated concentrations of arsenic, in the forms of arsenite, As(III), and/or arsenate, As(V), due to the high affinity of arsenic for sulfide mineral ores. This review summarizes the major geochemical processes controlling the release, speciation, fate, and distribution of inorganic arsenic in mine drainage and natural systems. Arsenic speciation depends highly on redox potential and pH of the solution, and arsenite can be oxidized to the less toxic arsenate form. Homogeneous oxidation of arsenite occurs rather slowly while its heterogeneous oxidation on mineral surfaces can greatly enhance the reaction rates. Little evidence suggests that precipitation reaction limits the concentrations of arsenic in natural water, while co-precipitation may lead to rapid arsenic removal when large amount of iron hydroxides precipitate out of the aqueous phase upon neutralization of the mine drainage. Both arsenate and arsenite adsorb on common metal oxides and clay minerals through formation of inner-sphere and/or outer-sphere complexes, controlling arsenic concentration in natural water bodies. Arsenite adsorbs less strongly than arsenate in the typical pH range of natural water and is more mobile. Part of the adsorbed arsenic species can be exchanged by common anions (e.g., PO(4)(3-) and SO(4)(2-)), especially phosphate, which leads to their re-mobilization. Understanding the geochemistry of arsenic is helpful for predicting its mobility and fate in AMD and natural systems, and for designing of cost-effective remediation/treatment strategies to reduce the occurrence and risk of arsenic contamination. PMID:19070955

  15. Hydrochemistry, mineralogy and sulfur isotope geochemistry of acid mine drainage at the Mt. Morgan mine environment, Queensland, Australia

    Mineralogical, hydrochemical and S isotope data were used to constrain hydrogeochemical processes that produce acid mine drainage from sulfidic waste at the historic Mount Morgan Au-Cu mine, and the factors controlling the concentration of SO4 and environmentally hazardous metals in the nearby Dee River in Queensland, Australia. Some highly contaminated acid waters, with metal contents up to hundreds of orders of magnitude greater than the Australia-New Zealand environmental standards, by-pass the water management system at the site and drain into the adjacent Dee River. Mine drainage precipitates at Mt. Morgan were classified into 4 major groups and were identified as hydrous sulfates and hydroxides of Fe and Al with various contents of other metals. These minerals contain adsorbed or mineralogically bound metals that are released into the water system after rainfall events. Sulfate in open pit water and collection sumps generally has a narrow range of S isotope compositions (δ 34S = 1.8-3.7%o) that is comparable to the orebody sulfides and makes S isotopes useful for tracing SO4 back to its source. The higher δ 34S values for No. 2 Mill Diesel sump may be attributed to a difference in the source. Dissolved SO4 in the river above the mine influence and 20 km downstream show distinctive heavier isotope compositions (δ 34S = 5.4-6.8%o). The Dee River downstream of the mine is enriched in 34S (δ 34S = 2.8-5.4%o) compared with mine drainage possibly as a result of bacterial SO4 reduction in the weir pools, and in the water bodies within the river channel. The SO4 and metals attenuate downstream by a combination of dilution with the receiving waters, SO4 reduction, and the precipitation of Fe and Al sulfates and hydroxides. It is suggested here that in subtropical Queensland, with distinct wet and dry seasons, temporary reducing environments in the river play an important role in S isotope systematics

  16. The geochemistry of rare earth elements (REE) in acid mine drainage from the Sitai coal mine, Shanxi Province, North China

    In this paper, geochemical characteristics of rare earth elements (REE) in acid mine drainage (AMD) from the Sitai coal mine of Shanxi Province, North China were investigated by determining concentrations of dissolved REEs and major solutes in the AMD samples, concentrations of REEs in the AMD precipitate samples and country rock samples (mudstone and coal), and modeling REEs species in the AMD. The results show that AMD in the Sitai coal mine have high REEs and SO42- concentrations in comparison with several terrestrial waters worldwide. The REE speciation modeling indicates that sulfate complexes (LnSO4+, > 60%) and free metal species (Ln3+, 20%-40%) are dominant REEs species in the AMD. AMD of the Sitai coal mine also shows a middle REE-enriched NASC (North American Shale Composite)-normalized pattern. The authors suggest that both REE sulfates (LnSO4+) in the AMD and country rock of coal measures are possible reasons for middle REE-enriched NASC-normalized pattern of the Sitai coal mine AMD. Further work on the AMD precipitates is needed to obtain more information on the origin of the middle REE-enriched NASC-normalized patterns. (author)

  17. Synthesising acid mine drainage to maintain and exploit indigenous mining micro-algae and microbial assemblies for biotreatment investigations.

    Orandi, Sanaz; Lewis, David M

    2013-02-01

    The stringent regulations for discharging acid mine drainage (AMD) has led to increased attention on traditional or emerging treatment technologies to establish efficient and sustainable management for mine effluents. To assess new technologies, laboratory investigations on AMD treatment are necessary requiring a consistent supply of AMD with a stable composition, thus limiting environmental variability and uncertainty during controlled experiments. Additionally, biotreatment systems using live cells, particularly micro-algae, require appropriate nutrient availability. Synthetic AMD (Syn-AMD) meets these requirements. However, to date, most of the reported Syn-AMDs are composed of only a few selected heavy metals without considering the complexity of actual AMD. In this study, AMD was synthesised based on the typical AMD characteristics from a copper mine where biotreatment is being considered using indigenous AMD algal-microbes. Major cations (Ca, Na, Cu, Zn, Mg, Mn and Ni), trace metals (Al, Fe, Ag, Na, Co, Mo, Pb and Cr), essential nutrients (N, P and C) and high SO(4) were incorporated into the Syn-AMD. This paper presents the preparation of chemically complex Syn-AMD and the challenges associated with combining metal salts of varying solubility that is not restricted to one particular mine site. The general approach reported and the particular reagents used can produce alternative Syn-AMD with varying compositions. The successful growth of indigenous AMD algal-microbes in the Syn-AMD demonstrated its applicability as appropriate generic media for cultivation and maintenance of mining microorganisms for future biotreatment studies. PMID:22684898

  18. Impact of acid mine drainage from mining exploitations on the Margajita River basin and the Hatillo reservoir (Dominican Republic)

    Mining of the Pueblo Viejo high-sulphidation epithermal deposit (Dominican Republic) leads to environmental impact due to the formation of acid mine drainage associated with the oxidative dissolution of sulphides and sulpho salts. In addition to the very low pH, the acid waters are capable of transporting away from the mining areas high concentrations of metals and metalloids in solution. In the present work, a geochemical study of sediments deposited in the Hatillo reservoir is carried out. This reservoir is fed by the Margajita and Yuna streams which transport leachates from the Pueblo Viejo and Falcondo-Bonao (Cr-Ni) mining areas, respectively. The results show that these sediments have very high concentrations of Fe, Al and sulphate, along with significant amounts of As, Zn and Te, which are of especial environmental concern. The main contributor to this metal discharge into the reservoir is the Margajita stream, whereas the Yuna stream does not transport significant amounts of metals in solution due to its neutral pH, although it is likely that metals such as Mn, Cr, Ni and Co can be mobilised as a particulate. (Author) 5 refs.

  19. Selective recovery of Cu, Zn, and Ni from acid mine drainage.

    Park, Sang-Min; Yoo, Jong-Chan; Ji, Sang-Woo; Yang, Jung-Seok; Baek, Kitae

    2013-12-01

    In Korea, the heavy metal pollution from about 1,000 abandoned mines has been a serious environmental issue. Especially, the surface waters, groundwaters, and soils around mines have been contaminated by heavy metals originating from acid mine drainage (AMD) and mine tailings. So far, AMD was considered as a waste stream to be treated to prevent environmental pollutions; however, the stream contains mainly Fe and Al and valuable metals such as Ni, Zn, and Cu. In this study, Visual MINTEQ simulation was carried out to investigate the speciation of heavy metals as functions of pH and neutralizing agents. Based on the simulation, selective pH values were determined to form hydroxide or carbonate precipitates of Cu, Zn, and Ni. Experiments based on the simulation results show that the recovery yield of Zn and Cu were 91 and 94 %, respectively, in a binary mixture of Cu and Zn, while 95 % of Cu and 94 % of Ni were recovered in a binary mixture of Cu and Ni. However, the recovery yield and purity of Zn and Ni were very low because of similar characteristics of Zn and Ni. Therefore, the mixture of Cu and Zn or Cu and Ni could be recovered by selective precipitation via pH adjustment; however, it is impossible to recover selectively Zn and Ni in the mixture of them. PMID:23754100

  20. Bio-Remediation of Acid Mine Drainage in the Sarcheshmeh Porphyry Copper Mine by Fungi: Batch and Fixed Bed Process

    Hanieh Soleimanifar

    2012-12-01

    Full Text Available Acid mine drainage (AMD containing high concentrations of iron and sulphate, low pH and variableconcentrations of heavy metals leads to many environmental problems. The concentrations of Cu and Mnare high in the AMD of the Sarcheshmeh porphyry copper mine, Kerman province, south of Iran. In thisstudy, the bio-remediation of Cu and Mn ions from acid mine drainage was investigated using two nativefungi called Aspergillus niger and Phanerochaete chrysosporium which were extracted from the soil andsediment samples of the Shour River at the Sarcheshmeh mine. The live fungi was first harvested andthen killed by boiling in 0.5 N NaOH solution. The biomass was finally dried at 60 C for 24 h andpowdered. The optimum biosorption parameters including pH, temperature, the amount of biosorbent andcontact time were determined in a batch system. The optimum pH varied between 5 and 6. It was foundthat the biosorption process increased with an increase in temperature and the amount of biosorbent.Biosorption data were attempted by Langmuir and Freundlich isotherm models and showed a good match.Kinetic studies were also carried out in the present study. The results show that the second-order kineticsmodel fits well the experimental data. The biosorption experiments were further investigated with acontinuous system to compare the biosorption capacities of two systems. The results show thatbiosorption process using a continuous system increases efficiency up to 99%. A desorption process waseventually performed in order to recover Copper and Manganese ions. This process was successful andfungi could be used again.

  1. Applications of multi-season hyperspectral remote sensing for acid mine water characterization and mapping of secondary iron minerals associated with acid mine drainage

    Davies, Gwendolyn E.

    Acid mine drainage (AMD) resulting from the oxidation of sulfides in mine waste is a major environmental issue facing the mining industry today. Open pit mines, tailings ponds, ore stockpiles, and waste rock dumps can all be significant sources of pollution, primarily heavy metals. These large mining-induced footprints are often located across vast geographic expanses and are difficult to access. With the continuing advancement of imaging satellites, remote sensing may provide a useful monitoring tool for pit lake water quality and the rapid assessment of abandoned mine sites. This study explored the applications of laboratory spectroscopy and multi-season hyperspectral remote sensing for environmental monitoring of mine waste environments. Laboratory spectral experiments were first performed on acid mine waters and synthetic ferric iron solutions to identify and isolate the unique spectral properties of mine waters. These spectral characterizations were then applied to airborne hyperspectral imagery for identification of poor water quality in AMD ponds at the Leviathan Mine Superfund site, CA. Finally, imagery varying in temporal and spatial resolutions were used to identify changes in mineralogy over weathering overburden piles and on dry AMD pond liner surfaces at the Leviathan Mine. Results show the utility of hyperspectral remote sensing for monitoring a diverse range of surfaces associated with AMD.

  2. Use of natural and applied tracers to guide targeted remediation efforts in an acid mine drainage system, Colorado Rockies, USA

    Cowie, Rory; Williams, Mark W.; Wireman, Mike; Runkel, Robert L.

    2014-01-01

    Stream water quality in areas of the western United States continues to be degraded by acid mine drainage (AMD), a legacy of hard-rock mining. The Rico-Argentine Mine in southwestern Colorado consists of complex multiple-level mine workings connected to a drainage tunnel discharging AMD to passive treatment ponds that discharge to the Dolores River. The mine workings are excavated into the hillslope on either side of a tributary stream with workings passing directly under the stream channel. There is a need to define hydrologic connections between surface water, groundwater, and mine workings to understand the source of both water and contaminants in the drainage tunnel discharge. Source identification will allow targeted remediation strategies to be developed. To identify hydrologic connections we employed a combination of natural and applied tracers including isotopes, ionic tracers, and fluorescent dyes. Stable water isotopes (δ18O/δD) show a well-mixed hydrological system, while tritium levels in mine waters indicate a fast flow-through system with mean residence times of years not decades or longer. Addition of multiple independent tracers indicated that water is traveling through mine workings with minimal obstructions. The results from a simultaneous salt and dye tracer application demonstrated that both tracer types can be successfully used in acidic mine water conditions.

  3. Use of Natural and Applied Tracers to Guide Targeted Remediation Efforts in an Acid Mine Drainage System, Colorado Rockies, USA

    Rory Cowie

    2014-03-01

    Full Text Available Stream water quality in areas of the western United States continues to be degraded by acid mine drainage (AMD, a legacy of hard-rock mining. The Rico-Argentine Mine in southwestern Colorado consists of complex multiple-level mine workings connected to a drainage tunnel discharging AMD to passive treatment ponds that discharge to the Dolores River. The mine workings are excavated into the hillslope on either side of a tributary stream with workings passing directly under the stream channel. There is a need to define hydrologic connections between surface water, groundwater, and mine workings to understand the source of both water and contaminants in the drainage tunnel discharge. Source identification will allow targeted remediation strategies to be developed. To identify hydrologic connections we employed a combination of natural and applied tracers including isotopes, ionic tracers, and fluorescent dyes. Stable water isotopes (δ18O/δD show a well-mixed hydrological system, while tritium levels in mine waters indicate a fast flow-through system with mean residence times of years not decades or longer. Addition of multiple independent tracers indicated that water is traveling through mine workings with minimal obstructions. The results from a simultaneous salt and dye tracer application demonstrated that both tracer types can be successfully used in acidic mine water conditions.

  4. Solubility relationships of aluminium and iron minerals associated with acid mine drainage

    The ability to properly manage the oxidation of pyritic minerals and associated acid mine drainage is dependent upon understanding the chemistry of the disposal environment. One accepted disposal method is placing pyritic-containing materials in the groundwater environment. The objective of this study was to examine solubility relationships of Al and Fe minerals associated with pyritic waste disposed in a low leaching aerobic saturated environment. Two eastern oil shales were used in this oxidizing equilibration study, a New Albany Shale (unweathered, 4.6 percent pyrite), and a Chattanooga Shale (weathered, 1.5 percent pyrite). Oil shale samples were equilibrated with distilled-deionized water from 1 to 180 d with a 1:1 solid-to-solution ratio. The suspensions were filtered and the clear filtrates were analyzed for total cations and anions. Ion activities were calculated from total concentrations. Below pH 6.0, depending upon SO42- activity, Al3+ solubility was controlled by AlOHSO4 (solid phase) for both shales. The results of this study indicate that below pH 6.0, Al3+ and Fe3+ solubilities, are limited by basic Al and Fe sulfate solid phases (AlOHSO4(s) and FeHSO4(s)). The results from this study further indicate that the acidity in oil shale waters is produced from the hydrolysis of Al3+ and Fe3+ activities in solution. These results indicate a fundamental change in the stoichiometric equations used to predict acidity from iron sulfide oxidation. The results of this study also indicate that water quality predictions associated with acid mine drainage can be based on fundamental thermodynamic relationships. As a result, waste management decisions can be based on waste-specific/site test methods

  5. Humic substances increase survival of freshwater shrimp Caridina sp. D to acid mine drainage.

    Holland, Aleicia; Duivenvoorden, Leo J; Kinnear, Susan H W

    2013-02-01

    Humic substances (HS) are known to decrease the toxicity of heavy metals to aquatic organisms, and it has been suggested that they can provide buffering protection in low pH conditions. Despite this, little is known about the ability for HS to increase survival to acid mine drainage (AMD). In this study, the ability of HS to increase survival of the freshwater shrimp (Caridina sp. D sensu Page et al. in Biol Lett 1:139-142, 2005) to acid mine drainage was investigated using test waters collected from the Mount Morgan open pit in Central Queensland with the addition of Aldrich humic acid (AHA). The AMD water from the Mount Morgan open pit is highly acidic (pH 2.67) as well as contaminated with heavy metals (1780 mg/L aluminum, 101 mg/L copper [Cu], 173 mg/L manganese, 51.8 mg/L zinc [Zn], and 51.8 mg/L iron). Freshwater shrimp were exposed to dilutions in the range of 0.5 % to 5 % AMD water with and without the addition of 10 or 20 mg/L AHA. In the absence of HS, all shrimp died in the 2.5 % AMD treatment. In contrast, addition of HS increased survival in the 2.5 % AMD treatment by ≤66 % as well as significantly decreased the concentration of dissolved Cu, cobalt, cadmium, and Zn. The decreased toxicity of AMD in the presence of HS is likely to be due to complexation and precipitation of heavy metals with the HS; it is also possible that HS caused changes to the physiological condition of the shrimp, thus increasing their survival. These results are valuable in contributing to an improved understanding of potential role of HS in ameliorating the toxicity of AMD environments. PMID:23135152

  6. Effects of acid mine drainage on a headwater stream ecosystem in Colorado

    The ecological effects of acid mine drainage were investigated during the summer of 1993 on St. Kevin Gulch, a headwater stream near Leadville, Colorado. The stream currently receives acidic water from an abandoned mine. The pH downstream of the mine is between 3.5 and 4.5, and several metals exceed concentrations toxic to aquatic organisms. Zinc is present at especially high concentrations (1 to 10 mg/L) Furthermore, the stream bottom is covered with a thick layer of iron hydroxide precipitates. Effects on stream biota have been dramatic. Aquatic flora in the affected reach is limited to a green filamentous alga, Ulothrix subtilissima. Macroinvertebrate densities are significantly lower in the affected reach (mean = 99 indiv/m2; SD = 88 indiv/M2) compared to an upstream (pristine) reference reach (mean = 1,735 indiv/m2; SD = 652 indiv/M2). Functional processes were also studied in the stream. Net primary production (NPP) was measured during midday with recirculating chambers. Production was significantly lower in the affected reach (mean NPP 13.3 MgO2hr-1m-2; SD = 87 MgO2hr-1m-2) than the upstream reference reach (NPP = 64.1 MgO2hr-1m-2; SD = 27.7 MgO2hr-1m-2). Decomposition, measured with litter bags, was also lower in the affected reach than the upstream site. In 1994, St. Kevin Gulch is scheduled to undergo remediation that will treat the acidic water from the mine. Further studies on this stream will provide information on the recovery processes in lotic ecosystems

  7. Efficacy assessment of acid mine drainage treatment with coal mining waste using Allium cepa L. as a bioindicator.

    Geremias, Reginaldo; Bortolotto, Tiago; Wilhelm-Filho, Danilo; Pedrosa, Rozangela Curi; de Fávere, Valfredo Tadeu

    2012-05-01

    The aim of this study was to evaluate the efficacy of the treatment of acid mine drainage (AMD) with calcinated coal mining waste using Allium cepa L. as a bioindicator. The pH values and the concentrations of aluminum, iron, manganese, zinc, copper, lead and sulfate were determined before and after the treatment of the AMD with calcinated coal mining waste. Allium cepa L. was exposed to untreated and treated AMD, as well as to mineral water as a negative control (NC). At the end of the exposure period, the inhibition of root growth was measured and the mean effective concentration (EC(50)) was determined. Oxidative stress biomarkers such as lipid peroxidation (TBARS), protein carbonyls (PC), catalase activity (CAT) and reduced glutathione levels (GSH) in the fleshy leaves of the bulb, as well as the DNA damage index (ID) in meristematic cells, were evaluated. The results indicated that the AMD treatment with calcinated coal mining waste resulted in an increase in the pH and an expressive removal of aluminum, iron, manganese and zinc. A high sub-chronic toxicity was observed when Allium cepa L. was exposed to the untreated AMD. However, after the treatment no toxicity was detected. Levels of TBARS and PC, CAT activity and the DNA damage index were significantly increased (Ptreatment and biomonitoring of these types of environmental contaminants. PMID:22239909

  8. Impact of Acid Mine Drainage on the hydrogeological system at Sia, Cyprus

    Ng, Stephen; Malpas, John

    2013-04-01

    Discontinued mining of the volcanogenic massive sulphide ore bodies of Cyprus has left significant environmental concerns including Acid Mine Drainage. Remnant sulphide ore and tailings in waste dumps react with oxygenated rainwater to produce sulphuric acid, a process which is multiplied when metal-loving acidophilic bacteria are present. Given that Cyprus has a Mediterranean climate, characterized by its warm and dry summers and cool and wet winters, the low pH effluent with high levels of trace elements, particularly metals, is leached out of the waste tips particularly during the wet season. The Sia site includes an open mine-pit lake, waste rock and tailings dumps, a river leading to a downstream dam-lake, and a localised groundwater system. The study intends to: identify the point source and nature of contamination; analyze the mechanism and results of local acid generation; and understand how the hydrogeological system responds to seasonal variations. During two sampling campaigns, in the wet and dry seasons of 2011, water samples were collected from the mine pit lake, from upstream of the adjacent river down to the dam catchment, and from various boreholes close to the sulphide mine. The concentration of ions in waters varies between wet and dry seasons but, in both, relative amounts are directly related to pH. In the mine-pit lake, Fe, Mn, Mg, Cu, Pb, Zn, Ni, Co and Cd are found in higher concentrations in the dry season, as a result of substantial evaporation of water. The Sia River runs continuously in the wet season, and waters collected close to the waste tips have pH as low as 2.5 and higher concentrations of Al, Cu, Fe and Zn. Further downstream there is a significant decrease in trace metal contents with a concomitant rise of pH. Al and Fe dominate total cation content when pH is lower than 4. Al is derived from the weathering of clay minerals, especially during the wet season. Fe is derived from the oxidation of pyrite. Once pH's exceed 4, a white

  9. The Regulation of Acid Mine Drainage in South Africa: Law and Governance Perspectives

    Loretta Feris

    2014-12-01

    Full Text Available Acid mine drainage (AMD is arguably one of the most serious environmental concerns in South Africa. AMD is a legacy left behind by abandoned, derelict and defunct mines, and is a continuing by-product of existing mining activities. In addition to its environmental impacts, AMD will also impact on all the parameters of sustainability, including ecological, social and economic concerns. In particular, AMD is set to affect infrastructure, displace people and affect their livelihoods, influence economic activity, impact on the resource extraction industry, and affect South Africa's policies and actions in relation to climate change and its efforts to move towards a low carbon economy; and it will test the efficiency of regulatory interventions emanating from both the private and the public sector to the extreme. Given these pervasive challenges, in this article we provide a survey of the AMD problem in South Africa through the law and governance lens. We commence by highlighting the various issues and challenges that result from AMD in the environmental context on the one hand, and the law and governance context on the other hand. We then describe the many provisions of the regulatory framework that we believe would be instrumental in responding to the threat. We conclude the article with brief remarks on what we believe are important considerations in the future regulation of AMD.

  10. Iron-mineral accretion from acid mine drainage and its application in passive treatment.

    Florence, K; Sapsford, D J; Johnson, D B; Kay, C M; Wolkersdorfer, C

    2016-06-01

    This study demonstrates substantial removal of iron (Fe) from acid mine drainage (pH ≈3) in a passive vertical flow reactor (VFR) with an equivalent footprint of 154 m(2) per L/s mine water and residence times of >23 h. Average Fe removal rate was 67% with a high of 85% over the 10-month trial. The fraction of Fe passing a 0.22 µm filter (referred to here as Fe-filt) was seen to be removed in the VFR even when Fe(II) was absent, indicating that the contribution of microbial Fe(II) oxidation and precipitation was not the dominant removal mechanism in the VFR. Removal rates of Fe-filt in the VFR were up to 70% in residence times as low as 8 h compared with laboratory experiments where much smaller changes in Fe-filt were observed over 60 h. Centrifugation indicated that 80-90% of the influent Fe had particle sizes water was contacted with VFR sludge, the Fe-filt fraction was destabilized, leading to an appreciably higher removal of this fraction. Heterogeneous precipitation and/or aggregation of nanoparticulate Fe(III) precipitates are considered predominant removal mechanisms. Microbial analyses of the mine water revealed the abundance of extracellular polymeric substance-generating Fe-oxidizing bacterium 'Ferrovum myxofaciens', which may aid the removal of iron and explain the unusual appearance and physical properties of the sludge. PMID:26675674

  11. Geochemistry of rare earth elements in a passive treatment system built for acid mine drainage remediation.

    Prudêncio, Maria Isabel; Valente, Teresa; Marques, Rosa; Sequeira Braga, Maria Amália; Pamplona, Jorge

    2015-11-01

    Rare earth elements (REE) were used to assess attenuation processes in a passive system for acid mine drainage treatment (Jales, Portugal). Hydrochemical parameters and REE contents in water, soils and sediments were obtained along the treatment system, after summer and winter. A decrease of REE contents in the water resulting from the interaction with limestone after summer occurs; in the wetlands REE are significantly released by the soil particles to the water. After winter, a higher water dynamics favors the AMD treatment effectiveness and performance since REE contents decrease along the system; La and Ce are preferentially sequestered by ochre sludge but released to the water in the wetlands, influencing the REE pattern of the creek water. Thus, REE fractionation occurs in the passive treatment systems and can be used as tracer to follow up and understand the geochemical processes that promote the remediation of AMD. PMID:26247412

  12. TREATMENT OF ACID MINE DRAINAGE: I. EQUILIBRIUM BIOSORPTION OF ZINC AND COPPER ON NON-VIABLE ACTIVATED SLUDGE

    Biosorption is potentially attractive technology for treament of acid mine drainage for separation/recovery of metal ions and mitigation of their toxicity to sulfate reducing bacteria. This study describes the equilibrium biosorptio of Zn(II) and CU(II) by nonviable activated slu...

  13. In situ studies with Asian clams (Carbacula fluminea) detect acid mine drainage and nutrient inputs in low-order streams

    This study evaluates the correlation between transplanted Asiatic clam and indigenous community responses to acid mine drainage and nutrient loading in first-to-third-order streams, by comparing the toxicological endpoints of clam survival and growth with benthic macro-invertebrate community indices as community responses to both acid mine drainage and nutrient loading. Clam survival was found to be positively correlated with water column pH and negatively correlated with conductivity and metal concentrations. There was also a positive correlation with the relative abundance of the macro-invertebrate Ephemeroptera, the most sensitive taxonomic group, to acid mine drainage in this watershed. No correlation was found between clam growth and acid mine drainage inputs, but there was evidence of positive correlation with nitrate concentrations and the relative abundance of collector-filterer functional feeding groups. These results suggest that clam growth is related to nutrient levels and accurately reflect benthic macro-invertebrate responses to nutrient loading. 28 refs., 5 tabs., 1 fig

  14. In-stream chemical neutralization: A whole watershed approach to mitigating acid mine drainage

    The North Branch of the Potomac River is adversely affected by acid mine drainage (AMD) throughout its entire length. As an alternative to mine-mouth treatment methods an in-stream AMD-neutralization demonstration program for an approximately 25-mile segment of the North Branch of the Potomac River was designed and implemented. This river segment was ranked as the highest priority site in Maryland for a demonstration project owing to its combination of very poor water quality and excellent potential for supporting a recreational sport fishery in the absence of toxic metal and acid loadings. A whole-watershed approach employing Scandinavian doser technologies and calcium carbonate neutralizing agents is the basis for the North Branch Potomac River demonstration project. The project involves four phases: feasibility (1), design (2), implementation (3), and monitoring (4). This watershed approach to mitigating AMD is expected to restore circumneutrial water quality and to promote desirable fishery resources throughout the mainstem and selected tributaries of the North Branch of the Potomac River Upstream of Jennings Randolph Dam. This paper summarizes Phases 1--3 of the demonstration project

  15. Acid mine drainage and stream recovery: Effects of restoration on water quality, macroinvertebrates, and fish

    Williams K.M.

    2015-01-01

    Full Text Available Acid mine drainage (AMD is a prominent threat to water quality in many of the world’s mining districts as it can severely degrade both the biological community and physical habitat of receiving streams. There are relatively few long-term studies investigating the ability of stream ecosystems to recover from AMD. Here we assess watershed scale recovery of a cold-water stream from pollution by AMD using a 1967 survey of the biological and chemical properties of the stream as a pre-restoration benchmark. We sampled water chemistry, benthic macroinvertebrates, and fish throughout the watershed during the spring and summer of 2011. Water chemistry results indicated that pH and total alkalinity increased post-restoration, while acidity, sulfate, and iron concentrations decreased. Watershed-level taxa richness, local taxa richness, biomass, diversity, and density of macroinvertebrates were significantly higher post-restoration; however, %EPT was not significantly different. Fish species richness, density, and brook trout density were all significantly higher post-restoration. These results provide clear evidence that both abiotic and biotic components of streams can recover from AMD pollution.

  16. Application of fracture-flow hydrogeology to acid-mine drainage at the Bunker Hill Mine, Kellogg, Idaho

    Lachmar, Thomas E.

    1994-03-01

    The mechanics of groundwater flow through fractured rock has become an object of major research interest during recent years. This project has investigated the flow of groundwater through fractured Precambrian metaquartzite rocks in a portion of the Bunker Hill Mine near Kellogg, Idaho. Groundwater flow through these types of rocks is largely dependent upon the properties of fractures such as faults, joints and relict bedding planes. Groundwater that flows into the mine via the fractures is acidic and is contaminated by heavy metals, which results in a severe acid mine drainage problem. A more complete understanding of how the fractures influence the groundwater flow system is a prerequisite of the evaluation of reclamation alternatives to reduce acid drainage from the mine. Fracture mapping techniques were used to obtain detailed information on the fracture properties observed in the New East Reed drift of the Bunker Hill Mine. The information obtained includes fracture type, orientation, trace length, the number of visible terminations, roughness, waviness, infilling material, and a qualitative measure of the amount of water flowing through each fracture. The hydrogeologic field data collected include routine measurements of the discharge from four individual structural features and four areas where large quantities of water are discharging from vertical rock bolts, the depths to water in three piezometer nests at the ground surface, the pressure variations in four diamond drillholes, and constant discharge flow tests conducted on three of the diamond drillholes. The field data indicate that relict bedding planes are the primary conduits for groundwater flow, and suggest that the two major joint sets that are present connect water flowing through the discontinuous bedding planes. The three minor joint sets that are present do not seem to have a significant impact on groundwater flow, but along with the two major joint sets may store relatively large quantities of

  17. Effects of acid mine drainage on water, sediment and associated benthic macroinvertebrate communities

    The toxic constituents of abandoned mined land (AML) discharges (acidic pH, heavy metals, total suspended solids) are extremely toxic to aquatic life . Studies were undertaken to ascertain environmental impacts to the upper Powell River, Lee and Wise Counties, Va. These impacts included disruptions in physical water quality, sediment quality, altered benthic macroinvertebrate assemblages, and toxicity of the water column and sediments from short-term impairment bioassays, and the potential to bioaccumulate selected metals (Al, Fe, Mn, P, Zn, Cu, Mg, S, Ni, Cd) by periphyton and resident bivalves. Water chemistry and macroinvertebrate assemblages were collected at upstream control, just below acid mine drainage and other downstream sites. Selected trace metal concentrations (Al, Fe, Mn, P, Zn, Cu, Mg, S, Ni, Cd) were determined for water, sediment and resident bivalves using ICP-AES. Acidic pH ranged from 2.15--3.3 at three AML-influenced seeps and varied from 6.4--8.0 at reference stations. At one AML-influenced creek, acidic pH conditions worsened from summer to fall and eradicated aquatic life throughout a 1.5 km stretch of that creek as it flowed into another creek. An additional dilution of 3.4 km in the second creek was needed to nearly neutralize the acidic pH problem. Conductivity (umhos/cm) ranged from 32--278 at reference sites and from 245--4,180 at AML-impact sites. Benthic macroinvertebrate abundance and taxon richness were essentially eliminated in the seeps or reached numbers of 1 -3 taxa totaling < 10 organisms relative to reference areas where richness values were 12--17 and comprised 300--977 organisms. Concentrations of Fe, Al, Mg and Cu and Zn were highest in the environmentally stressed stations of low pH and high conductivity relative to the reference stations. Iron was, by far, the element in highest concentration followed by Al and Mg

  18. Trace metals of an acid mine drainage stream using a chemical model (WATEQ) and sediment analysis

    The high metal contents common to the discharge of acid-mine drainage (AMD) from mines and mine spoils is an environmental concern to both government and industry. This paper reports the results of investigation of the behavior of metals in an AMD system at a former surface coal mine in Tuscarawas County, Oh. AMD discharges from seeps travels, in respective order through a laminar flow stream; a Typha-dominated wetland; a turbulent flow stream; and a sediment retention pond. Dissolved metals (Fe, Mn, Zn, Cr, Cd, Cu, and Al) major and minor components, and other parameters (pH, dissolved oxygen and Eh) were measured in the AMD water at each sample location. A chemical mineral equilibrium model (WATEQ) was used to predict the minerals which should precipitate at each site. Results suggest that the seeps are supersaturated and should be precipitating hematite, goethite and magnetite (iron oxides), and siderite (iron carbonate), whereas water of the other downstream sites were at or below equilibrium conditions for these minerals. The hydrogeochemistry of the AMD was further studied using sequential chemical attacks on the precipitate sediment surface coatings, in order to determine metal concentrations in the exchangeable, carbonate, Fe-Mn oxyhydroxide, and oxidizable fractions. The carbonate and exchangeable fractions of the precipitate are dominated by Ca and Fe, as well as Mg in the carbonate fraction. The Fe-Mn oxyhydroxide fraction contained Fe, Al, Mn, Mg, and trace metals, and also contained the greatest concentration of total elements in the system. The Fe-Mn oxyhydroxide is therefore, the major sink for metals of this AMD system. The decrease in the concentration of metals in the sediment precipitates in the downstream locations, is consistent with WATEQ and water analysis results

  19. Coupling of hydrologic transport and chemical reactions in a stream affected by acid mine drainage

    Kimball, B.A.; Broshears, R.E.; Bencala, K.E.; McKnight, Diane M.

    1994-01-01

    Experiments in St. Kevin Gulch, an acid mine drainage stream, examined the coupling of hydrologic transport to chemical reactions affecting metal concentrations. Injection of LiCl as a conservative tracer was used to determine discharge and residence time along a 1497-m reach. Transport of metals downstream from inflows of acidic, metal-rich water was evaluated based on synoptic samples of metal concentrations and the hydrologic characteristics of the stream. Transport of SO4 and Mn was generally conservative, but in the subreaches most affected by acidic inflows, transport was reactive. Both 0.1-??m filtered and particulate Fe were reactive over most of the stream reach. Filtered Al partitioned to the particulate phase in response to high instream concentrations. Simulations that accounted for the removal of SO4, Mn, Fe, and Al with first-order reactions reproduced the steady-state profiles. The calculated rate constants for net removal used in the simulations embody several processes that occur on a stream-reach scale. The comparison between rates of hydrologie transport and chemical reactions indicates that reactions are only important over short distances in the stream near the acidic inflows, where reactions occur on a comparable time scale with hydrologic transport and thus affect metal concentrations.

  20. Accumulation of aluminium and iron by bryophytes in streams affected by acid-mine drainage

    Engleman, C.J.; McDiffett, W.F. [Bucknell University, Lewisburg, PA (United States). Dept. of Biology

    1996-12-31

    This paper examines the accumulation of two heavy metals (Al and Fe) by bryophytes in a northern Pennsylvania stream system affected by acid-mine drainage. Four sites within one watershed were selected on the basis of their pH and dissolved metal concentrations. Significant differences among sites were found with regard to bioaccumulation of Al an Fe. A negative relationship between pH and Fe concentrations in bryophyte tissues was found, with the highest accumulation of Fe observed at the most acidic site (pH 3.5), whereas accumulation of Al was highest at a site with an intermediate pH of 5.2. Bryophytes transplanted from a circum-neutral site to acidic sites showed highly significant increases in Fe and Al concentrations in tissues after 6 weeks, and transplants from more acidic sites to a circum-neutral site generally showed highly significant declines in Fe and Al concentration in tissues after the incubation period.

  1. Hydrogeochemical niches associated with hyporheic exchange beneath an acid mine drainage-contaminated stream

    Larson, Lance N.; Fitzgerald, Michael; Singha, Kamini; Gooseff, Michael N.; Macalady, Jennifer L.; Burgos, William

    2013-09-01

    Biological low-pH Fe(II)-oxidation creates terraced iron formations (TIFs) that remove Fe(III) from solution. TIFs can be used for remediation of acid mine drainage (AMD), however, as sediment depth increases, Fe(III)-reduction in anoxic subsurface areas may compromise treatment effectiveness. In this study we used near-surface electrical resistivity imaging (ERI) and in situ pore-water samplers to spatially resolve bulk conductivity changes within a TIF formed in a stream emanating from a large abandoned deep clay mine in Cambria County, Pennsylvania, USA. Because of the high fluid electrical conductivity of the emergent AMD (1860 μS), fresh water (42 μS) was added as a dilution tracer to visualize the spatial and temporal extent of hyporheic exchange and to characterize subsurface flow paths. Distinct hydrogeochemical niches were identified in the shallow subsurface beneath the stream by overlaying relative groundwater velocities (derived from ERI) with pore-water chemistry profiles. Niches were classified based on relatively “fast” versus “slow” rates of hyporheic exchange and oxic versus anoxic conditions. Pore-water concentrations and speciation of iron, pH, and redox potential differed between subsurface flow regimes. The greatest extent of hyporheic exchange was beneath the center of the stream, where a shallower (70 cm) Fe(II)-oxidizing zone. At these locations, relatively slower groundwater exchange may promote biotic Fe(II)-oxidation and improve the long-term stability of Fe sequestered in TIFs.

  2. Oxidative Precipitation of Manganese from Acid Mine Drainage by Potassium Permanganate

    Regeane M. Freitas

    2013-01-01

    Full Text Available Although oxidative precipitation by potassium permanganate is a widely recognised process for manganese removal, research dealing with highly contaminated acid mine drainage (AMD has yet to be performed. The present study investigated the efficiency of KMnO4 in removing manganese from AMD effluents. Samples of AMD that originated from inactive uranium mine in Brazil were chemically characterised and treated by KMnO4 at pH 3.0, 5.0, and 7.0. Analyses by Raman spectroscopy and geochemical modelling using PHREEQC code were employed to assess solid phases. Results indicated that the manganese was rapidly oxidised by KMnO4 in a process enhanced at higher pH. The greatest removal, that is, 99%, occurred at pH 7.0, when treated waters presented manganese levels as low as 1.0 mg/L, the limit established by the Brazilian legislation. Birnessite (MnO2, hausmannite (Mn3O4, and manganite (MnOOH were detected by Raman spectroscopy. These phases were consistently identified by the geochemical model, which also predicted phases containing iron, uranium, manganese, and aluminium during the correction of the pH as well as bixbyite (Mn2O3, nsutite (MnO2, pyrolusite (MnO2, and fluorite (CaF2 following the KMnO4 addition.

  3. Acid mine drainage abatement using fluidized bed combustion ash grout after geophysical site characterization

    Pyritic coal refuse and pit cleanings buried in a 15-ha (37-acre) surface mine produce severe acid mine drainage (AMD). The pyritic material had been buried in discrete piles or pods in the backfill. The pods and the resulting contaminant plumes were initially defined using geophysical techniques and were confirmed by drilling. Fluidized bed combustion (FBC) ash, mixed with water to form a grout, was used in different ways to isolate the pyritic material from water and oxygen. In the first approach, grout was pressure injected directly into the buried pods to fill the void spaces within the pods and to coat the pyritic materials with a cementitious layer. A second approach used the grout to divert water from specific areas. Pods which did not accept grout because of a clay matrix were isolated from percolating water with a cap and trench seal of the grout. The grout was also used in certain areas to blanket the clay pit floor since clays are believed to be a primary source of aluminum at this site. In certain areas, the AMD migrates downward though fractures in the pit floor to the groundwater table. Grout was injected along the fractures in some of these areas to seal them. This would inhibit further AMD migration toward one of the receiving streams. The initial postgrouting water quality data have been encouraging

  4. Quantitative microbial community analysis of three different sulfidic mine tailing dumps generating acid mine drainage.

    Kock, Dagmar; Schippers, Axel

    2008-08-01

    The microbial communities of three different sulfidic and acidic mine waste tailing dumps located in Botswana, Germany, and Sweden were quantitatively analyzed using quantitative real-time PCR (Q-PCR), fluorescence in situ hybridization (FISH), catalyzed reporter deposition-FISH (CARD-FISH), Sybr green II direct counting, and the most probable number (MPN) cultivation technique. Depth profiles of cell numbers showed that the compositions of the microbial communities are greatly different at the three sites and also strongly varied between zones of oxidized and unoxidized tailings. Maximum cell numbers of up to 10(9) cells g(-1) dry weight were determined in the pyrite or pyrrhotite oxidation zones, whereas cell numbers in unoxidized tailings were significantly lower. Bacteria dominated over Archaea and Eukarya at all tailing sites. The acidophilic Fe(II)- and/or sulfur-oxidizing Acidithiobacillus spp. dominated over the acidophilic Fe(II)-oxidizing Leptospirillum spp. among the Bacteria at two sites. The two genera were equally abundant at the third site. The acidophilic Fe(II)- and sulfur-oxidizing Sulfobacillus spp. were generally less abundant. The acidophilic Fe(III)-reducing Acidiphilium spp. could be found at only one site. The neutrophilic Fe(III)-reducing Geobacteraceae as well as the dsrA gene of sulfate reducers were quantifiable at all three sites. FISH analysis provided reliable data only for tailing zones with high microbial activity, whereas CARD-FISH, Q-PCR, Sybr green II staining, and MPN were suitable methods for a quantitative microbial community analysis of tailings in general. PMID:18586975

  5. Effects of bacterial action on waste rock producing acid drainage in the Brazilian first uranium mine

    This work is an evolution of the methodology showed in the paper 'Study of waste of waste rock piles producing acid drainage in the Brazilian first uranium mine', also submitted for INAC2009. Therefore, the present work also related to the determination of chemical species leaching from waste rock pile 4 (WRP4) of the Uranium Mine and Milling Facility located in the Pocos de Caldas Plateau, as well as the generation of acid waters. With the previous experimental setup, it has been observed that not only water and available oxygen are significant to pyrite oxidation reaction, but bacterial activity as well. As a first approach, the present work addresses the same experiment, but now testing without the influence of bacterial action. Therefore, the new methodology and experimental setup is now capable of determining the acidity of water in contact with material from the WRP4 and the concentration of chemical species dissolved as function of time. Such would also show the extent of bacterial action interference on the pyrite oxidation reaction. Results are based on mass balances comparing concentrations of chemical species in the waste rock before the experiment and in the waste rock plus the remaining water after the experiment. In addition, the evolution of the pH and EMF (electromotive force) values along with chemical species quantified through the experiment are presented through graphics. That is followed by discussions on the significance of such results in terms of concentration of the involved chemical species. The present work has also shown the need of improving the injection of air into the system. A more sophisticated experimental setup should be assembled in the near future, which would allow the quantification of differences between experimental tests with and without bacterial action. (author)

  6. The Wheal Jane wetlands model for bioremediation of acid mine drainage

    Acid mine drainage (AMD) is a widespread environmental problem associated with both working and abandoned mining operations. As part of an overall strategy to determine a long-term treatment option for AMD, a pilot passive treatment plant was constructed in 1994 at Wheal Jane Mine in Cornwall, UK. The plant consists of three separate systems, each containing aerobic reed beds, anaerobic cell and rock filters, and represents the largest European experimental facility of its kind. The systems only differ by the type of pretreatment utilised to increase the pH of the influent minewater (pH <4): lime dosed (LD), anoxic limestone drain (ALD) and lime free (LF), which receives no form of pretreatment. Historical data (1994-1997) indicate median Fe reduction between 55% and 92%, sulphate removal in the range of 3-38% and removal of target metals (cadmium, copper and zinc) below detection limits, depending on pretreatment and flow rates through the system. A new model to simulate the processes and dynamics of the wetlands systems is described, as well as the application of the model to experimental data collected at the pilot plant. The model is process based, and utilises reaction kinetic approaches based on experimental microbial techniques rather than an equilibrium approach to metal precipitation. The model is dynamic and utilises numerical integration routines to solve a set of differential equations that describe the behaviour of 20 variables over the 17 pilot plant cells on a daily basis. The model outputs at each cell boundary are evaluated and compared with the measured data, and the model is demonstrated to provide a good representation of the complex behaviour of the wetland system for a wide range of variables

  7. Bioassessment of a combined chemical-biological treatment for synthetic acid mine drainage.

    Pagnanelli, F; De Michelis, I; Di Muzio, S; Ferella, F; Vegliò, F

    2008-11-30

    In this work, ecotoxicological characteristics of synthetic samples of acid mine drainage (AMD) before and after a combined chemical-biological treatment were investigated by using Lepidium sativum and Daphnia magna. AMD treatment was performed in a two-column apparatus consisting of chemical precipitation by limestone and biological refinement by sulphate reducing bacteria. Synthetic samples of AMD before treatment were toxic for both L. sativum (germination index, G, lower than 10%) and D. magna (100% immobility) due to acid pH and presence of copper and zinc. Chemical treatment (raising pH to 5-6 and eliminating copper) generated effluents with reduced toxicity for L. sativum (G=33%), while 100% immobility was still observed for D. magna. Dynamic trends of toxicity for the first and fifth outputs of the biological column denoted a gradual improvement leading to hormesis for Lepidium (after the initial release of organic excess), while a constant residual toxicity remained for Daphnia (probably due to H(2)S produced by sulphate reducing bacteria). PMID:18394799

  8. Preparation of metal-resistant immobilized sulfate reducing bacteria beads for acid mine drainage treatment.

    Zhang, Mingliang; Wang, Haixia; Han, Xuemei

    2016-07-01

    Novel immobilized sulfate-reducing bacteria (SRB) beads were prepared for the treatment of synthetic acid mine drainage (AMD) containing high concentrations of Fe, Cu, Cd and Zn using up-flow anaerobic packed-bed bioreactor. The tolerance of immobilized SRB beads to heavy metals was significantly enhanced compared with that of suspended SRB. High removal efficiencies of sulfate (61-88%) and heavy metals (>99.9%) as well as slightly alkaline effluent pH (7.3-7.8) were achieved when the bioreactor was fed with acidic influent (pH 2.7) containing high concentrations of multiple metals (Fe 469 mg/L, Cu 88 mg/L, Cd 92 mg/L and Zn 128 mg/L), which showed that the bioreactor filled with immobilized SRB beads had tolerance to AMD containing high concentrations of heavy metals. Partially decomposed maize straw was a carbon source and stabilizing agent in the initial phase of bioreactor operation but later had to be supplemented by a soluble carbon source such as sodium lactate. The microbial community in the bioreactor was characterized by denaturing gradient gel electrophoresis (DGGE) and sequencing of partial 16S rDNA genes. Synergistic interaction between SRB (Desulfovibrio desulfuricans) and co-existing fermentative bacteria could be the key factor for the utilization of complex organic substrate (maize straw) as carbon and nutrients source for sulfate reduction. PMID:27058913

  9. Novel nickel resistance genes from the rhizosphere metagenome of plants adapted to acid mine drainage.

    Mirete, Salvador; de Figueras, Carolina G; González-Pastor, Jose E

    2007-10-01

    Metal resistance determinants have traditionally been found in cultivated bacteria. To search for genes involved in nickel resistance, we analyzed the bacterial community of the rhizosphere of Erica andevalensis, an endemic heather which grows at the banks of the Tinto River, a naturally metal-enriched and extremely acidic environment in southwestern Spain. 16S rRNA gene sequence analysis of rhizosphere DNA revealed the presence of members of five phylogenetic groups of Bacteria and the two main groups of Archaea mostly associated with sites impacted by acid mine drainage (AMD). The diversity observed and the presence of heavy metals in the rhizosphere led us to construct and screen five different metagenomic libraries hosted in Escherichia coli for searching novel nickel resistance determinants. A total of 13 positive clones were detected and analyzed. Insights about their possible mechanisms of resistance were obtained from cellular nickel content and sequence similarities. Two clones encoded putative ABC transporter components, and a novel mechanism of metal efflux is suggested. In addition, a nickel hyperaccumulation mechanism is proposed for a clone encoding a serine O-acetyltransferase. Five clones encoded proteins similar to well-characterized proteins but not previously reported to be related to nickel resistance, and the remaining six clones encoded hypothetical or conserved hypothetical proteins of uncertain functions. This is the first report documenting nickel resistance genes recovered from the metagenome of an AMD environment. PMID:17675438

  10. The chemistry of conventional and alternative treatment systems for the neutralization of acid mine drainage

    The oxidation of pyritic mining waste is a self-perpetuating corrosive process which generates acid mine drainage (AMD) effluent for centuries or longer. The chemical neutralization of these complex, buffered effluents result in unstable, metal-laden sludges, which require disposal to minimize long-term environmental consequences. A variety of passive treatment systems for AMD, developed in the past two decades, combine limestone and organic substrates in constructed wetlands. These systems work well initially but over the longer term fail due to clogging with and the depletion of available organic carbon. However, some ecologically engineered systems, which exploit the activities of acid reducing microbes in the sediment, rely on photosynthesis in the water column as a source of organic matter. The primary productivity in the water column, which also generates some alkalinity, provides electron donors for the microbial reduction processes in the sediment. In its consideration of 'passive' systems, the literature has placed undue emphasis on sulphate reduction; thermodynamical iron reduction is equally important as is the need to prevent iron oxidation. Secondary precipitates of iron play a significant role in sediment-driven biomineralization processes, which affect the anaerobic degradation of organic matter and the stability of the resulting metal sulfides. One such passive system, which utilized a floating root mass as a source of organic carbon, is described. An extensive review of the literature and the chemical and biogeochemical reactions of AMD treatment systems, lead to the conclusion, that sediment based ecological systems offer the greatest potential for the sustainable treatment of AMD

  11. The chemistry of conventional and alternative treatment systems for the neutralization of acid mine drainage.

    Kalin, Margarete; Fyson, Andrew; Wheeler, William N

    2006-08-01

    The oxidation of pyritic mining waste is a self-perpetuating corrosive process which generates acid mine drainage (AMD) effluent for centuries or longer. The chemical neutralization of these complex, buffered effluents result in unstable, metal-laden sludges, which require disposal to minimize long-term environmental consequences. A variety of passive treatment systems for AMD, developed in the past two decades, combine limestone and organic substrates in constructed wetlands. These systems work well initially but over the longer term fail due to clogging with and the depletion of available organic carbon. However, some ecologically engineered systems, which exploit the activities of acid reducing microbes in the sediment, rely on photosynthesis in the water column as a source of organic matter. The primary productivity in the water column, which also generates some alkalinity, provides electron donors for the microbial reduction processes in the sediment. In its consideration of 'passive' systems, the literature has placed undue emphasis on sulphate reduction; thermodynamical iron reduction is equally important as is the need to prevent iron oxidation. Secondary precipitates of iron play a significant role in sediment-driven biomineralization processes, which affect the anaerobic degradation of organic matter and the stability of the resulting metal sulfides. One such passive system, which utilized a floating root mass as a source of organic carbon, is described. An extensive review of the literature and the chemical and biogeochemical reactions of AMD treatment systems, lead to the conclusion, that sediment based ecological systems offer the greatest potential for the sustainable treatment of AMD. PMID:16375949

  12. The influence of biofilms on the migration of uranium in acid mine drainage (AMD) waters

    The uranium mine in Koenigstein (Germany) is currently in the process of being flooded. Huge mass of Ferrovum myxofaciens dominated biofilms are growing in the acid mine drainage (AMD) water as macroscopic streamers and as stalactite-like snottites hanging from the ceiling of the galleries. Microsensor measurements were performed in the AMD water as well as in the biofilms from the drainage channel on-site and in the laboratory. The analytical data of the AMD water was used for the thermodynamic calculation of the predominance fields of the aquatic uranium sulfate (UO2SO4) and UO2++ speciation as well as of the solid uranium species Uranophane [Ca(UO2)2(SiO3OH)2·5H2O] and Coffinite [U(SiO4)1-x(OH)4x], which are defined in the stability field of pH > 4.8 and Eh 0 and Eh 4.8. Even analysis by Energy-filtered Transmission Electron Microscopy (EF-TEM) and electron energy loss spectroscopy (EELS) within the biofilms did not provide any microscopic or spectroscopic evidence for the presence of uranium immobilization. In laboratory experiments the first phase of the flooding process was simulated by increasing the pH of the AMD water. The results of the experiments indicated that the F. myxofaciens dominated biofilms may have a substantial impact on the migration of uranium. The AMD water remained acid although it was permanently neutralized with the consequence that the retention of uranium from the aqueous solution by the formation of solid uranium species will be inhibited. - Highlights: → Redox potential and pH of the biofilm differ significantly compared to the AMD water. → Formation of an aqueous uranium(VI) sulfate complex in the biofilm and in the AMD water. → Experiments revealed that the F. myxofaciens dominated biofilms have a substantial impact on the migration of uranium. → Due to homeostatic mechanisms the microbes maintain their intracellular pH even when the pH of the water increases.

  13. The use of coal combustion by-products to control acid mine drainage

    The placement of an alkaline coal combustion by-product (CCB) in abandoned, reclaimed or active surface coal mines is intended to reduce the amount of acid mine drainage (AMD) produced at such sites. The CCB may limit acid formation by several mechanisms: neutralization, inhibition of acid forming bacteria, encapsulation of the pyrite or water diversion. Water quality changes have been monitored at three sites where a grout containing fly ash was injected after reclamation. Comparison of water quality, before and after grouting, indicated small increases in pH and decreases in acidity at discharge points. The concentrations of calcium and magnesium in water samples generally increased. Concentrations of trace elements were found to be generally comparable in treated and untreated areas. When grouted and ungrouted areas were compared, the effect of the fly ash was shown to be localized in the areas of injection. These studies indicated that fly ash is an effective reagent for control of AMD, but that large volumes are required to treat a site. To corroborate the field results, a series of column leaching tests were conducted to determine the release of trace elements from CCB as a function of pH. A one kg fly ash sample is placed in each of several 5-cm by 1 m acrylic columns. The material is leached at a nominal rate of 250 nL/d for 60 days. Lixiviants include deionized water, artificial groundwater, synthetic precipitation, and dilute solutions of acetic acid, sodium carbonate, sulfuric acid, and ferric chloride. Leachate is analyzed for the trace elements antimony, arsenic, barium, boron, cadmium, chromium, cobalt, copper, lead, nickel, selenium, and zinc. Leachate data, analyzed as the mass extracted with respect to the concentration in the solid, indicate that the release of trace elements is variable. Depending on the pH or the leachant solution, the mass release of arsenic, copper, nickel and zinc may exceed 20 pct of the amount present in the original sample

  14. Uranium pollution in an estuary affected by pyrite acid mine drainage and releases of naturally occurring radioactive materials

    Highlights: → Huelva estuary is affected by former phosphogypsum releases and pyrite acid mine drainage. → Time evolution of uranium concentration is analyzed after halting of NORM releases. → Two new contamination sources are preventing the complete uranium cleaning: (1) The leaching of phosphogypsum stacks located close to Tinto River. (2) Pyrite acid mine drainage. → High uranium concentrations are dissolved in water and precipitate subsequently. - Abstract: After the termination of phosphogypsum discharges to the Huelva estuary (SW Spain), a unique opportunity was presented to study the response of a contaminated environmental compartment after the cessation of its main source of pollution. The evolution over time of uranium concentrations in the estuary is presented to supply new insights into the decontamination of a scenario affected by Naturally Occurring Radioactive Material (NORM) discharges. The cleaning of uranium isotopes from the area has not taken place as rapidly as expected due to leaching from phosphogypsum stacks. An in-depth study using various techniques of analysis, including 234U/238U and 230Th/232Th ratios and the decreasing rates of the uranium concentration, enabled a second source of uranium contamination to be discovered. Increased uranium levels due to acid mine drainage from pyrite mines located in the Iberian Pyrite Belt (SW Spain) prevent complete uranium decontamination and, therefore, result in levels nearly twice those of natural background levels.

  15. BONE MEAL AS ALTERNATIVE TREATMENT FOR ACIDIC AND METAL CONTAMINATED ACID MINE DRAINAGE WATER EFFLUENT: LAB SCALE

    Carolyn Payus

    2014-01-01

    Full Text Available The typical methods of treatment for acidic and metal contaminated water effluent such as the Acid Mine Drainage (AMD will always focus on either civil engineering methods, such as disposal, excavation, drainage and encapsulation or process based technologies such as effluent washing and treatment. These techniques are not environmental friendly, costly and unsustainable, thus environmental damaging. Nowadays, there is a growing need for an alternative remediation treatment that is innovative and more natural in order to prevent pollution in the environment. Therefore, in this study, a new alternative treatment, that is more organic, biodegradable and cost effective, using bone meal was presented. In this research, bone meal comprising of chicken bones were used as an alternative passive treatment to determine its potential in neutralizing and removing heavy metals from the abandoned cooper mine, Mamut Acid Mine Drainage (AMD waste water effluent. A pretreatment process for bone meal was performed by incineration process where it was heated up in the furnace at 500°C for 24 h after it was cleaned, crushed, boiled and dried. Batch experiment test has been carried out to test whether the selected bone meal sizes 45, 75 and 150 µm was able to neutralize the AMD Mamut water samples. Inductive Plasma Couple-Atomic Emission Spectrometry (ICP-AES test was carried out to test the concentration of the heavy metals before and after the treatment. The surface morphology of bone meal was examined by Scanning Electron Microscopy (SEM. Enlargement of pores after the neutralization treatment was seen on the surface morphology of the bone meal by SEM analyses. A significant rising of pH from 2.98 to 5.69 within 6 h 30 min was observed during neutralization process and 99% removal of Fe, Zn, Al, Cu and 36% removal of Mg concentration was achieved after the treatment through the neutralization treatment of the AMD waste water effluent. The results from this

  16. Characterization and Localization of Iron-Oxidizing Proteins in Acid Mine Drainage Biofilms

    Chan, C. S.; Thelen, M. P.; Hwang, M.; Banfield, J. F.

    2005-12-01

    As molecular geomicrobiologists, we are interested in the microbially-produced molecules that effect geochemical transformations, particularly proteins involved in lithotrophic energy generation. We have identified two such proteins produced by Leptospirillum group II microbes, which dominate biofilms floating on acidic waters in the Richmond Mine at Iron Mountain, CA. Leptospirillum generates energy by iron oxidation, producing the ferric iron catalyst responsible for pyrite oxidation, subsequent acid generation and toxic metal release. We have shown that a small (~16 kDa) soluble protein, cytochrome-579, extracted from environmental biofilm samples is capable of iron oxidation in vitro, consistent with prior studies on similar cytochromes from L. ferriphilum and ferrooxidans (Blake et al., 1993; Hart et al., 1991). The abundance of cyt579 and its ability to oxidize iron makes it a key link between microbial metabolism and acid mine drainage. Given the importance of cyt579 in biofilm sustenance as well as acid generation, we want to understand more about its distribution and also the architecture of the biofilm environment in which it functions. Using transmission electron microscopy (TEM) on ultrathin sections, we observe biofilms as thin as 15 microns with densely-packed cells in a matrix of polymers. To localize cyt579 in the biofilm, we purified the protein and developed antibodies for immunolabeling. The antibodies were shown to be highly specific for cyt579 using Western blots of whole biofilm lysate. Fluorescence- and gold-labeled secondary antibodies were used to visualize immunolabeled biofilms by confocal laser scanning microscopy and TEM, respectively. Preliminary results suggest that the cytochrome is on the bacterial cell surface or in the periplasm but not throughout the biofilm, as we had postulated due to the abundance of cytochrome in extracellular fractions of biofilm samples. These localization studies will be helpful in determining the

  17. Characterization of the microbial acid mine drainage microbial community using culturing and direct sequencing techniques.

    Auld, Ryan R; Myre, Maxine; Mykytczuk, Nadia C S; Leduc, Leo G; Merritt, Thomas J S

    2013-05-01

    We characterized the bacterial community from an AMD tailings pond using both classical culturing and modern direct sequencing techniques and compared the two methods. Acid mine drainage (AMD) is produced by the environmental and microbial oxidation of minerals dissolved from mining waste. Surprisingly, we know little about the microbial communities associated with AMD, despite the fundamental ecological roles of these organisms and large-scale economic impact of these waste sites. AMD microbial communities have classically been characterized by laboratory culturing-based techniques and more recently by direct sequencing of marker gene sequences, primarily the 16S rRNA gene. In our comparison of the techniques, we find that their results are complementary, overall indicating very similar community structure with similar dominant species, but with each method identifying some species that were missed by the other. We were able to culture the majority of species that our direct sequencing results indicated were present, primarily species within the Acidithiobacillus and Acidiphilium genera, although estimates of relative species abundance were only obtained from direct sequencing. Interestingly, our culture-based methods recovered four species that had been overlooked from our sequencing results because of the rarity of the marker gene sequences, likely members of the rare biosphere. Further, direct sequencing indicated that a single genus, completely missed in our culture-based study, Legionella, was a dominant member of the microbial community. Our results suggest that while either method does a reasonable job of identifying the dominant members of the AMD microbial community, together the methods combine to give a more complete picture of the true diversity of this environment. PMID:23485423

  18. Recovery of Rare Earth Elements and Yttrium from Passive-Remediation Systems of Acid Mine Drainage.

    Ayora, Carlos; Macías, Francisco; Torres, Ester; Lozano, Alba; Carrero, Sergio; Nieto, José-Miguel; Pérez-López, Rafael; Fernández-Martínez, Alejandro; Castillo-Michel, Hiram

    2016-08-01

    Rare earth elements and yttrium (REY) are raw materials of increasing importance for modern technologies, and finding new sources has become a pressing need. Acid mine drainage (AMD) is commonly considered an environmental pollution issue. However, REY concentrations in AMD can be several orders of magnitude higher than in naturally occurring water bodies. With respect to shale standards, the REY distribution pattern in AMD is enriched in intermediate and valuable REY, such as Tb and Dy. The objective of the present work is to study the behavior of REY in AMD passive-remediation systems. Traditional AMD passive remediation systems are based on the reaction of AMD with calcite-based permeable substrates followed by decantation ponds. Experiments with two columns simulating AMD treatment demonstrate that schwertmannite does not accumulate REY, which, instead, are retained in the basaluminite residue. The same observation is made in two field-scale treatments from the Iberian Pyrite Belt (IPB, southwest Spain). On the basis of the amplitude of this process and on the extent of the IPB, our findings suggest that the proposed AMD remediation process can represent a modest but suitable REY source. In this sense, the IPB could function as a giant heap-leaching process of regional scale in which rain and oxygen act as natural driving forces with no energy investment. In addition to having environmental benefits of its treatment, AMD is expected to last for hundreds of years, and therefore, the total reserves are practically unlimited. PMID:27351211

  19. Stable isotope geochemistry of acid mine drainage; experimental oxidation of pyrite

    Sulfate and water from experiments in which pyrite was oxidized at a pH of 2.0 were analyzed for sulfur and oxygen stable isotopes. Experiments were conducted under both aerobic and anaerobic sterile conditions, as well as under aerobic conditions in the presence of Thiobacillus ferrooxidans, to elucidate the pathways of oxidation. Oxygen isotope fractionation between SO42- and H2O varied from +4.0 per mille (anaerobic, sterile) to +18.0 per mille (aerobic, with T. ferrooxidans). The oxygen isotope composition of dissolved oxygen utilized in both chemical and microbially-mediated oxidation was also determined (+11.4 per mille, by T. ferrooxidans; +18.4 per mille, chemical). Contributions of water-derived oxygen and dissolved oxygen to the sulfate produced in the oxidation of pyrite could thus be estimated. Water-derived oxygen constituted from 23 to approx. 100 per cent of the oxygen in the sulfate produced in the experiments, and this closely approximates the range of contribution in natural acid mine drainage. Oxidation of sulfides in anaerobic, water-saturated environments occurs primarily by chemical oxidation pathways, whereas oxidation of sulfides in well-aerated, unsaturated zone environments occurs dominantly by microbially-mediated pathways. (author)

  20. Radium and barium removal through blending hydraulic fracturing fluids with acid mine drainage.

    Kondash, Andrew J; Warner, Nathaniel R; Lahav, Ori; Vengosh, Avner

    2014-01-21

    Wastewaters generated during hydraulic fracturing of the Marcellus Shale typically contain high concentrations of salts, naturally occurring radioactive material (NORM), and metals, such as barium, that pose environmental and public health risks upon inadequate treatment and disposal. In addition, fresh water scarcity in dry regions or during periods of drought could limit shale gas development. This paper explores the possibility of using alternative water sources and their impact on NORM levels through blending acid mine drainage (AMD) effluent with recycled hydraulic fracturing flowback fluids (HFFFs). We conducted a series of laboratory experiments in which the chemistry and NORM of different mix proportions of AMD and HFFF were examined after reacting for 48 h. The experimental data combined with geochemical modeling and X-ray diffraction analysis suggest that several ions, including sulfate, iron, barium, strontium, and a large portion of radium (60-100%), precipitated into newly formed solids composed mainly of Sr barite within the first ∼ 10 h of mixing. The results imply that blending AMD and HFFF could be an effective management practice for both remediation of the high NORM in the Marcellus HFFF wastewater and beneficial utilization of AMD that is currently contaminating waterways in northeastern U.S.A. PMID:24367969

  1. Wine wastes as carbon source for biological treatment of acid mine drainage.

    Costa, M C; Santos, E S; Barros, R J; Pires, C; Martins, M

    2009-05-01

    Possible use of wine wastes containing ethanol as carbon and energy source for sulphate-reducing bacteria (SRB) growth and activity in the treatment of acid mine drainage (AMD) is studied for the first time. The experiments were performed using anaerobic down-flow packed bed reactors in semi-continuous systems. The performance of two bioreactors fed with wine wastes or ethanol as carbon sources is compared in terms of sulphate reduction, metals removal and neutralization. The results show that efficient neutralization and high sulphate removal (>90%) were attained with the use of wine wastes as substrate allowing the production of effluents with concentrations below the required local legislation for irrigation waters. This is only possible provided that the AMD and wine wastes are contacted with calcite tailing, a waste material that neutralizes and provides buffer capacity to the medium. The removal of metals using wine wastes as carbon source was 61-91% for Fe and 97% for both Zn and Cu. The lower removal of iron, when wine waste is used instead of ethanol, may be due to the presence of iron-chelating compounds in the waste, which prevent the formation of iron sulphide, and partial unavailability of sulphide because of re-oxidation to elemental sulphur. However, that did not affect significantly the quality of the effluent for irrigation. This work demonstrates that wine wastes are a potential alternative to traditional SRB substrates. This finding has direct implication to sustainable operation of SRB bioreactors for AMD treatment. PMID:19201010

  2. Separate recovery of copper and zinc from acid mine drainage using biogenic sulfide

    Precipitation of metals from acid mine drainage (AMD) using sulfide gives the possibility of selective recovery due to different solubility product of each metal. Using sulfate reducing bacteria to produce sulfide for that purpose is advantageous due to in situ and on-demand sulfide production. In this study, separate precipitation of Cu and Zn was studied using sulfide produced in anaerobic baffled reactor (ABR). ABR fed with ethanol (1340 mg/L chemical oxygen demand (COD)) and sulfate (2000 mg/L) gave a stable performance with 65% sulfate reduction, 85% COD removal and around 320 mg/L sulfide production. Cu was separately precipitated at low pH (pH 2 gas. Cu precipitation was complete within 45-60 min and Zn did not precipitate during Cu removal. The Cu precipitation rate increased with initial Cu concentration. After selective Cu precipitation, Zn recovery was studied using ABR effluent containing sulfide and alkalinity. Depending on initial sulfide/Zn ratio, removal efficiency varied between 84 and 98%. The low pH of Zn bearing AMD was also increased to neutral values using alkalinity produced by sulfate reducing bacteria in ABR. The mode of particle size distribution of ZnS and CuS precipitates was around 17 and 46 μm, respectively.

  3. Biogeochemistry of the compost bioreactor components of a composite acid mine drainage passive remediation system

    The compost bioreactor ('anaerobic cell') components of three composite passive remediation systems constructed to treat acid mine drainage (AMD) at the former Wheal Jane tin mine, Cornwall, UK were studied over a period of 16 months. While there was some amelioration of the preprocessed AMD in each of the three compost bioreactors, as evidenced by pH increase and decrease in metal concentrations, only one of the cells showed effective removal of the two dominant heavy metals (iron and zinc) present. With two of the compost bioreactors, concentrations of soluble (ferrous) iron draining the cells were significantly greater than those entering the reactors, indicating that there was net mobilisation (by reductive dissolution) of colloidal and/or solid-phase ferric iron compounds within the cells. Soluble sulfide was also detected in waters draining all three compost bioreactors which was rapidly oxidised, in contrast to ferrous iron. Oxidation and hydrolysis of iron, together with sulfide oxidation, resulted in reacidification of processed AMD downstream of the compost bioreactors in two of the passive treatment systems. The dominant cultivatable microorganism in waters draining the compost bioreactors was identified, via analysis of its 16S rRNA gene, as a Thiomonas sp. and was capable of accelerating the dissimilatory oxidation of both ferrous iron and reduced sulfur compounds. Sulfate-reducing bacteria (SRB) were also detected, although only in the bioreactor that was performing well were these present in significant numbers. This particular compost bioreactor had been shut down for 10 months prior to the monitoring period due to operational problems. This unforeseen event appears to have allowed more successful development of AMD-tolerant and other microbial populations with critical roles in AMD bioremediation, including neutrophilic SRB (nSRB), in this compost bioreactor than in the other two, where the throughput of AMD was not interrupted. This study has

  4. Microbial diversity at the moderate acidic stage in three different sulfidic mine tailings dumps generating acid mine drainage.

    Korehi, Hananeh; Blöthe, Marco; Schippers, Axel

    2014-11-01

    In freshly deposited sulfidic mine tailings the pH is alkaline or circumneutral. Due to pyrite or pyrrhotite oxidation the pH is dropping over time to pH values <3 at which acidophilic iron- and sulfur-oxidizing prokaryotes prevail and accelerate the oxidation processes, well described for several mine waste sites. The microbial communities at the moderate acidic stage in mine tailings are only scarcely studied. Here we investigated the microbial diversity via 16S rRNA gene sequence analysis in eight samples (pH range 3.2-6.5) from three different sulfidic mine tailings dumps in Botswana, Germany and Sweden. In total 701 partial 16S rRNA gene sequences revealed a divergent microbial community between the three sites and at different tailings depths. Proteobacteria and Firmicutes were overall the most abundant phyla in the clone libraries. Acidobacteria, Actinobacteria, Bacteroidetes, and Nitrospira occurred less frequently. The found microbial communities were completely different to microbial communities in tailings at

  5. Molecular analysis of benthic biofilms from acidic coal mine drainage, Pennsylvania, USA

    Mills, D. B.; Jones, D. S.; Burgos, W. D.; Macalady, J. L.

    2010-12-01

    Acid mine drainage (AMD) is a common environmental problem in Pennsylvania that results from the oxidation of sulfide minerals exposed at abandoned coal mines. In these systems, acidophilic microorganisms catalyze the oxidation of ferrous (Fe2+) to ferric iron (Fe3+), which precipitates as iron-hydroxide minerals. To develop and improve low-pH bioremediation strategies, characterization of the microbiology of AMD systems is essential. An acidic (pH 2-4) AMD spring known as ‘Lower Red Eyes’ in Gallitzan State Forest, PA, is fed by anoxic groundwater with ferrous iron concentrations above 550 mg/L. More than half of the total iron is removed after the springwater flows downstream over 80 m of stagnant pools and iron-oxide terraces. We used fluorescence in situ hybridization (FISH) and 16S rDNA cloning to characterize the microbial communities from orange sediments and green benthic biofilms. 16S rDNA sequences were extracted from a green biofilm found in a pH 3.5 pool 10 m downstream of the emergence. Based on chloroplast 16S rDNA sequences and morphological characteristics, we found that Euglena mutabilis was the dominant eukaryotic organism from this location. Euglena mutabilis is a photosynthetic protozoan common in acidic and heavy metal affected environments, and likely contributes to the precipitation of iron oxides through the production of molecular oxygen. Bacterial 16S rDNA sequences were cloned from iron-oxide sediments with orange cauliflower morphology 27 m downstream from the spring emergence. More than 60% of bacterial sequences retrieved from the orange sediment sample are related to the iron-oxidizing Betaproteobacterium Ferrovum myxofaciens. Other bacterial sequences include relatives of iron-oxidizing genera in the Gammaproteobacteria, Betaproteobacteria, and Actinobacteria. FISH analyses show that Betaproteobacteria-dominated communities are associated with Euglena in multiple upstream locations where pH is above 3.0. Using light microscopy

  6. Adsorption compared with sulfide precipitation as metal removal processes from acid mine drainage in a constructed wetland

    Machemer, Steven D.; Wildeman, Thomas R.

    1992-01-01

    Metal removal processes from acid mine drainage were studied in an experimental constructed wetland in the Idaho Springs-Central City mining district of Colorado. The wetland was designed to passively remove heavy metals from the mine drainage flowing from the Big Five Tunnel. Concurrent studies were performed in the field on the waters flowing from the wetland and in the laboratory on the wetland substrate. Both studies suggest that there is competition for organic adsorption sites among Fe, Cu, Zn and Mn. Iron and Cu appear to be more strongly adsorbed than Zn and Mn. The adsorption of metals varies with the fluctuation of pH in the outflow water. Also indicated by field and laboratory studies is the microbial reduction of sulfate with a corresponding increase in the sulfide concentration of the water. As sulfide is generated. Cu and Zn are completely removed. The field results suggest that upon start up of a constructed wetland, the adsorption of dissolved metals onto organic sites in the substrate material will be an important process. Over time, sulfide precipitation becomes the dominant process for metal removal from acid mine drainage.

  7. Colloidal precipitates related to Acid Mine Drainage: bacterial diversity and micro fungi-heavy metal interactions

    Lucchetti, G.; Carbone, C.; Consani, S.; Zotti, M.; Di Piazza, S.; Pozzolini, M.; Giovine, M.

    2015-12-01

    In Acid Mine Drainage (AMD) settings colloidal precipitates control the mobility of Potential Toxic Elements (PTEs). Mineral-contaminant relationships (i.e. adsorption, ion-exchange, desorption) are rarely pure abiotic processes. Microbes, mainly bacteria and microfungi, can catalyze several reactions modifying the element speciation, as well as the bioavailability of inorganic pollutants. Soil, sediments, and waters heavily polluted with PTEs through AMD processes are a potential reservoir of extremophile bacteria and fungi exploitable for biotechnological purposes. Two different AMD related colloids, an ochraceous precipitate (deposited in weakly acidic conditions, composed by nanocrystalline goethite) and a greenish-blue precipitate (deposited at near-neutral pH, composed by allophane + woodwardite) were sampled. The aims of this work were to a) characterize the mycobiota present in these colloidal minerals by evaluating the presence of alive fungal propagules and extracting bacteria DNA; b) verify the fungal strains tolerance, and bioaccumulation capability on greenish-blue and ZnSO4 enriched media; c) evaluate potential impact of bacteria in the system geochemistry. The preliminary results show an interesting and selected mycobiota able to survive under unfavourable environmental conditions. A significant number of fungal strains were isolated in pure culture. Among them, species belonging to Penicillium and Trichoderma genera were tested on both greenish-blue and ZnSO4 enriched media. The results show a significant tolerance and bioaccumulation capability to some PTEs. The same colloidal precipitates were processed to extract bacteria DNA by using a specific procedure developed for sediments. The results give a good yield of nucleic acids and a positive PCR amplification of 16S rDNA accomplished the first step for future metagenomic analyses.

  8. Acute toxicity of an acid mine drainage mixing zone to juvenile bluegill and largemouth bass

    Henry, T.B.; Irwin, E.R.; Grizzle, J.M.; Wildhaber, M.L.; Brumbaugh, W.G.

    1999-01-01

    The toxicity of an acid mixing zone produced at the confluence of a stream that was contaminated by acid mine drainage (AMD) and a pH-neutral stream was investigated in toxicity tests with juvenile bluegill Lepomis macrochirus and largemouth bass Micropterus salmoides. Fish mortalities in instream cages located in the mixing zone, below the mixing zone, and upstream in both tributaries were compared to determine relative toxicity at each site. In all tests and for both species, significantly higher mortality was observed in the mixing zone than at any other location, including the acid stream, which had lower pH (2.9-4.3). The mixing zone was defined chemically by rapid precipitation of dissolved aluminum and iron, which arrived from the low-pH stream, and by the presence of white precipitates, which were attached to the substratum and which extended below the confluence. Possible seasonal changes in mixing zone toxicity were investigated by conducting field tests with bluegill in June, July, and August 1996 and in January 1997 and by conducting field tests with largemouth bass in April and May 1997. Toxicity was not significantly different at the extremes of temperature, pH, and metal concentration that occurred in June and July, as compared with January. Toxicity was significantly lower in August; however, elevated stream discharge during the August test may have disturbed mixing zone characteristics. High toxicity in AMD mixing zones may lower the survival of fishes in streams, reduce available habitat, and impede movements of migratory fish.

  9. Hydrogeochemical characteristics of streams with and without acid mine drainage impacts: A paired catchment study in karst geology, SW China

    Sun, Jing; Tang, Changyuan; Wu, Pan; Strosnider, William H. J.; Han, Zhiwei

    2013-11-01

    A paired catchment study was used to assess karst hydrogeochemistry of two streams.Chemistry of streams with and without acid mine drainage (AMD) was very different.The observation was supported by PHREEQC modeling of equilibrium conditions.Ionic fluxes of AMD-impacted water were higher than that of non-AMD-impacted water.The higher ionic fluxes were predominantly controlled by the oxidation of pyrite.

  10. The role of sulfate and ionic strength on the shift from acid to alkaline mine drainage in southwest Pennsylvania

    Four Mile Run, Latrobe, PA, receives discharges from abandoned deep mines. In 1971, the effluent was characterized as having low pH, high acidity, and high concentrations of iron, manganese, and sulfate. After 22 yr of neglect, the water flow rate, pH, and alkalinity all increased, while the acidity, iron, manganese, and sulfate concentrations decreased. The overall loading of iron and sulfate to the stream has not changed significantly. This change from acid to alkaline drainage is fairly typical for mine effluent in the surrounding area. However, the mechanism for change is not well understood. Laboratory studies have shown that the neutralization rate of marble chips (CaCO3) is depressed by high ionic strength or elevated levels of sulfate. The decrease in sulfate levels may be an important factor contributing to the change in water quality discharged into Four Mile Run. A similar kinetic phenomenon may occur with mine spoils and anoxic drains

  11. THE RESPONSE OF THE PERIPHYTIC DIATOM COMMUNITY TO ACID MINE DRAINAGE POLLUTION

    Andreea Ciorba; R. Barreiro Lozano

    2004-01-01

    This paper proposes to relate the principal characteristics of diatom community (species richness, biodiversity, community biomass, diatom indices) to the stress induced by acidification and high levels of metal. The study was done in a mine drainage affected area in Galicia (NW Spain) by comparing periphytic diatom communities from polluted streams to ones in supposedly clean waters. The change in the dominant species was the clearest response to AMD pollution while species richness and div...

  12. Development and Validation of an Acid Mine Drainage Treatment Process for Source Water

    Lane, Ann [Battelle Memorial Institute, Columbus, OH (United States)

    2016-03-01

    Throughout Northern Appalachia and surrounding regions, hundreds of abandoned mine sites exist which frequently are the source of Acid Mine Drainage (AMD). AMD typically contains metal ions in solution with sulfate ions which have been leached from the mine. These large volumes of water, if treated to a minimum standard, may be of use in Hydraulic Fracturing (HF) or other industrial processes. This project’s focus is to evaluate an AMD water treatment technology for the purpose of providing treated AMD as an alternative source of water for HF operations. The HydroFlex™ technology allows the conversion of a previous environmental liability into an asset while reducing stress on potable water sources. The technology achieves greater than 95% water recovery, while removing sulfate to concentrations below 100 mg/L and common metals (e.g., iron and aluminum) below 1 mg/L. The project is intended to demonstrate the capability of the process to provide AMD as alternative source water for HF operations. The second budget period of the project has been completed during which Battelle conducted two individual test campaigns in the field. The first test campaign demonstrated the ability of the HydroFlex system to remove sulfate to levels below 100 mg/L, meeting the requirements indicated by industry stakeholders for use of the treated AMD as source water. The second test campaign consisted of a series of focused confirmatory tests aimed at gathering additional data to refine the economic projections for the process. Throughout the project, regular communications were held with a group of project stakeholders to ensure alignment of the project objectives with industry requirements. Finally, the process byproduct generated by the HydroFlex process was evaluated for the treatment of produced water against commercial treatment chemicals. It was found that the process byproduct achieved similar results for produced water treatment as the chemicals currently in use. Further

  13. Predicting taxonomic and functional structure of microbial communities in acid mine drainage.

    Kuang, Jialiang; Huang, Linan; He, Zhili; Chen, Linxing; Hua, Zhengshuang; Jia, Pu; Li, Shengjin; Liu, Jun; Li, Jintian; Zhou, Jizhong; Shu, Wensheng

    2016-06-01

    Predicting the dynamics of community composition and functional attributes responding to environmental changes is an essential goal in community ecology but remains a major challenge, particularly in microbial ecology. Here, by targeting a model system with low species richness, we explore the spatial distribution of taxonomic and functional structure of 40 acid mine drainage (AMD) microbial communities across Southeast China profiled by 16S ribosomal RNA pyrosequencing and a comprehensive microarray (GeoChip). Similar environmentally dependent patterns of dominant microbial lineages and key functional genes were observed regardless of the large-scale geographical isolation. Functional and phylogenetic β-diversities were significantly correlated, whereas functional metabolic potentials were strongly influenced by environmental conditions and community taxonomic structure. Using advanced modeling approaches based on artificial neural networks, we successfully predicted the taxonomic and functional dynamics with significantly higher prediction accuracies of metabolic potentials (average Bray-Curtis similarity 87.8) as compared with relative microbial abundances (similarity 66.8), implying that natural AMD microbial assemblages may be better predicted at the functional genes level rather than at taxonomic level. Furthermore, relative metabolic potentials of genes involved in many key ecological functions (for example, nitrogen and phosphate utilization, metals resistance and stress response) were extrapolated to increase under more acidic and metal-rich conditions, indicating a critical strategy of stress adaptation in these extraordinary communities. Collectively, our findings indicate that natural selection rather than geographic distance has a more crucial role in shaping the taxonomic and functional patterns of AMD microbial community that readily predicted by modeling methods and suggest that the model-based approach is essential to better understand natural

  14. Combination of Successive Alkalinity Producing System (SAPS) and Aeration for Passive Treatment of Highly Acidic Mine Drainage

    Oh, C.; Ji, S.

    2015-12-01

    Passive treatment system has been widely used for remediation of mine drainage since its advantage of low installation and maintenance cost. The system, however, has also a disadvantage in assuring remediation and management efficiency if the drainage is highly acidic mine drainage. To remediate acid mine drainage (AMD) especially showing high acidity, passive treatment system which consists of successive alkalinity producing system (SAPS) and subsequent aeration pond was proposed and its mechanisms and efficiency was evaluated in this research. Target AMD was obtained from Waryong coal mine and showed typical characteristics of AMD having high metal concentration and low pH (acidity > 300 mg/L as CaCO3). Four experimental cases were conducted; untreated, treated with SAPS, treated with aeration, treated with SAPS and aeration to compare role and mechanism of each unit. Between organic matter and limestone layer which constitute SAPS, the former eliminated most of Fe(III) and Al in the AMD so that the latter was kept from being clogged by precipitates. Net acidity of the AMD rapidly decreased by supplement of alkalinity at the limestone layer. A primary function of SAPS, producing alkalinity constantly without clogging, was attained due to addition a portion of limestone particle into the organic matter layer. The discharge from SAPS had low ORP and DO values because of an anaerobic environment formed at the organic matter layer although its alkalinity was increased. This water quality was unfavorable for Fe(II) to be oxidized. Installation of aeration pond after SAPS, therefore, could be effective way of enhancing oxidation rate of Fe(II). Among the experimental cases, the combination of SAPS and aeration pond was only able to remediate the AMD. This concluded that to remediate highly acidic mine drainage with passive treatment system, three critical conditions were required; pre-precipitation of Fe(III) and Al at organic matter layer in SAPS, constant alkalinity

  15. Microbial Communities and a Novel Symbiotic Interaction in Extremely Acidic Mine Drainage at Iron Mountain, California

    Baker, B. J.; Banfield, J. F.

    2002-12-01

    Culture-independent studies of microbial communities in the acid mine drainage (AMD) system associated with the Richmond ore body at Iron Mountain, CA, demonstrated that the total number of prokaryote lineages is small compared to other environments. Phylogenetic analyses of 232 small subunit ribosomal RNA (rRNA) genes from six clone libraries revealed some novel lines of descent. Many of the novel clones were from libraries constructed from subaerial biofilms associated with fine grained pyrite. The clones form several distinct groups within the order Thermoplasmatales and are most closely related to Ferroplasma spp. and Thermoplasma spp. Another novel group detected in a pH 1.4 pool and a pH 0.8 biofilm falls within the Rickettsiales (alpha-proteobacteria and related to mitochondria) and is most closely related to a-proteobacterial endosymbionts of Acanthamoeba spp. An oligonucleotide rRNA probe designed to target alpha-proteobacteria revealed that these are protist endosymbionts, and that they are associated with a small percentage (2%) of the total eukaryotes in samples from the Richmond mine. Measurements of the internal pH of these protists show that their cytosol is close to neutral. Thus, protists provide a habitat within the AMD system that is at least 5 pH units less acidic than the surroundings. The uncultured AMD endosymbionts have a conserved 273 nucleotide intervening sequence (IVS) in the variable V1 region of their 16S rRNA gene. The IVS does not match any sequence in current databases, but predicted secondary structure form well defined stem loops. The discovery of inserts within a highly conserved gene is extremely rare. At present we have not identified the protist host. However, it is interesting to note that protists previously shown to have a-proteobacterial endosymbionts possess 18S rRNA genes that contain both IVSs and group I introns. The possibility that the IVS in the AMD bacteria is a result of extensive genetic exchange between a

  16. Simulation of acid mine drainage generation around Küre VMS Deposits, Northern Turkey

    Demirel, Cansu; Kurt, Mehmet Ali; Çelik Balci, Nurgül

    2015-04-01

    This study investigated comparative leaching characteristics of acidophilic bacterial strains under shifting environmental conditions at proposed two stages as formation stage or post acidic mine drainage (AMD) generation. At the first stage, initial reactions associated with AMD generation was simulated in shaking flasks containing massive pyritic chalcopyrite ore by using a pure strain Acidithiobacillus ferrooxidans and a mixed culture of Acidithiobacillus sp. mostly dominated by A. ferrooxidans and A. thiooxidans at 26oC. At the second stage, long term bioleaching experiments were carried out with the same strains at 26oC and 40oC to investigate the leaching characteristics of pyritic chalcopyrite ore under elevated heavy metal and temperature conditions. During the experiments, physicochemical characteristics (e.i. Eh, pH, EC) metal (Fe, Co, Cu, Zn) and sulfate concentration of the experimental solution were monitored during 180 days. Significant acid generation and sulfate release were determined during bioleaching of the ore by mixed acidophilic cultures containing both iron and sulfur oxidizers. In the early stage of the experiments, heavy metal release from the ore was caused by generation of acid due to accelerated bacterial oxidation of the ore. Generally high concentrations of Co and Cu were released into the solution from the experiments conducted by pure cultures of Acidithiobacillus ferrooxidans whereas high Zn and Fe was released into the solution from the mixed culture experiments. In the later stage of AMD generation and post AMD, chemical oxidation is accelerated causing excessive amounts of contamination, even exceeding the amounts resulted from bacterial oxidation by mixed cultures. Acidithibacillus ferrooxidans was found to be more effective in leaching Cu, Fe and Co at higher temperatures in contrary to mixed acidophiles that are more prone to operate at optimal moderate conditions. Moreover, decreasing Fe values are noted in bioleaching

  17. Prediction of the long-term performance of green liquor dregs as a sealing layer to prevent the formation of acid mine drainage

    Mäkitalo, Maria; Lu, Jinmei; Maurice, Christian; Öhlander, Björn

    2015-01-01

    One of the mining industry's main concerns is the management of waste rock and tailings generated by sulfide ore extraction. Upon exposure of atmospheric oxygen, iron sulfides oxidize generating acidity. Infiltrating water form a metal-rich acidic leachate called acid mine drainage (AMD), that can cause serious environmental problems. Green liquor dregs (GLD) is a material that resists the passage of oxygen and water and could thus be used to seal mine wastes, preventing their oxidation and A...

  18. Toxicity and metal speciation in acid mine drainage treated by passive bioreactors

    Neculita, C.M.; Vigneaul, B.; Zagury, G.J. [Ecole Polytechnic, Montreal, PQ (Canada)

    2008-08-15

    Sulfate-reducing passive bioreactors treat acid mine drainage (AMD) by increasing its pH and alkalinity and by removing metals as metal sulfide precipitates. In addition to discharge limits based on physicochemical parameters, however, treated effluent is required to be nontoxic. Acute and sublethal toxicity was assessed for effluent from 3.5-L column bioreactors filled with mixtures of natural organic carbon sources and operated at different hydraulic retention times (HRTs) for the treatment of a highly contaminated AMD. Effluent was first tested for acute (Daphnia magna and Oncorhynchus mykiss) and sublethal (Pseudokirchneriella subcapitata, Ceriodaphnia dabia, and Lemna minor) toxicity. Acute toxicity was observed for D. magna, and a toxicity identification evaluation (TIE) procedure was then performed to identify potential toxicants. Finally, metal speciation in the effluent was determined using ultrafiltration and geochemical modeling for the interpretation of the toxicity results. The 10-d HRT effluent was nonacutely lethal for 0. mykiss but acutely lethal for D. magna. The toxicity to D. magna, however, was removed by 2 h of aeration, and the TIE procedure suggested iron as a cause of toxicity. Sublethal toxicity of the 10-d HRT effluent was observed for all test species, but it was reduced compared to the raw AMD and to a 7.3-d HRT effluent. Data regarding metal speciation indicated instability of both effluents during aeration and were consistent with the toxicity being caused by iron. Column bioreactors in operation for more than nine months efficiently improved the physicochemical quality of highly contaminated AMD at different HRTs.

  19. Utilizing acid mine drainage sludge and coal fly ash for phosphate removal from dairy wastewater.

    Wang, Y R; Tsang, Daniel C W; Olds, William E; Weber, Paul A

    2013-01-01

    This study aims to investigate a new and sustainable approach for the reuse of industrial by-products from wastewater treatment. The dairy industry produces huge volumes of wastewater, characterized by high levels of phosphate that can result in eutrophication and degradation of aquatic ecosystems. This study evaluated the application of acid mine drainage (AMD) sludge, coal fly ash, and lignite as low-cost adsorbents for the removal of phosphate from dairy wastewater. Material characterization using X-ray fluorescence, X-ray diffraction, and Brunauer-Emmett-Teller surface area analysis revealed significant amounts of crystalline/amorphous Fe/Al/Si/Ca-based minerals and large surface areas of AMD sludge and fly ash. Batch adsorption isotherms were best described using the Freundlich model. The Freundlich distribution coefficients were 13.7 mg(0.577) L(0.423) g(-1) and 16.9 mg(0.478) L(0.522) g(-1) for AMD sludge and fly ash, respectively, and the nonlinearity constants suggested favourable adsorption for column applications. The breakthrough curves of fixed-bed columns, containing greater than 10 wt% of the waste materials (individual or composite blends) mixed with sand, indicated that phosphate breakthrough did not occur within 100 pore volumes while the cumulative removal was 522 and 490 mg kg(-1) at 10 wt% AMD sludge and 10 wt% fly ash, respectively. By contrast, lignite exhibited negligible phosphate adsorption, possibly due to small amounts of inorganic minerals suitable for phosphate complexation and limited surface area. The results suggest that both AMD sludge and fly ash were potentially effective adsorbents if employed individually at a ratio of 10 wt% or above for column application. PMID:24617077

  20. MiniSipper: A new in situ water sampler for high-resolution, long-duration acid mine drainage monitoring

    Chapin, Thomas P.; Todd, Andrew S.

    2012-01-01

    Abandoned hard-rock mines can be a significant source of acid mine drainage (AMD) and toxic metal pollution to watersheds. In Colorado, USA, abandoned mines are often located in remote, high elevation areas that are snowbound for 7–8 months of the year. The difficulty in accessing these remote sites, especially during winter, creates challenging water sampling problems and major hydrologic and toxic metal loading events are often under sampled. Currently available automated water samplers are not well suited for sampling remote snowbound areas so the U.S. Geological Survey (USGS) has developed a new water sampler, the MiniSipper, to provide long-duration, high-resolution water sampling in remote areas. The MiniSipper is a small, portable sampler that uses gas bubbles to separate up to 250 five milliliter acidified samples in a long tubing coil. The MiniSipper operates for over 8 months unattended in water under snow/ice, reduces field work costs, and greatly increases sampling resolution, especially during inaccessible times. MiniSippers were deployed in support of an U.S. Environmental Protection Agency (EPA) project evaluating acid mine drainage inputs from the Pennsylvania Mine to the Snake River watershed in Summit County, CO, USA. MiniSipper metal results agree within 10% of EPA-USGS hand collected grab sample results. Our high-resolution results reveal very strong correlations (R2 > 0.9) between potentially toxic metals (Cd, Cu, and Zn) and specific conductivity at the Pennsylvania Mine site. The large number of samples collected by the MiniSipper over the entire water year provides a detailed look at the effects of major hydrologic events such as snowmelt runoff and rainstorms on metal loading from the Pennsylvania Mine. MiniSipper results will help guide EPA sampling strategy and remediation efforts in the Snake River watershed.

  1. THE RESPONSE OF THE PERIPHYTIC DIATOM COMMUNITY TO ACID MINE DRAINAGE POLLUTION

    Andreea Ciorba

    2004-01-01

    Full Text Available This paper proposes to relate the principal characteristics of diatom community (species richness, biodiversity, community biomass, diatom indices to the stress induced by acidification and high levels of metal. The study was done in a mine drainage affected area in Galicia (NW Spain by comparing periphytic diatom communities from polluted streams to ones in supposedly clean waters. The change in the dominant species was the clearest response to AMD pollution while species richness and diversity were sensitive only to high levels of pollution.

  2. Humic acid decreases acute toxicity and ventilation frequency in eastern rainbowfish (Melanotaenia splendida splendida) exposed to acid mine drainage.

    Holland, Aleicia; Duivenvoorden, Leo J; Kinnear, Susan H W

    2014-12-01

    Acid mine drainage (AMD) is a global problem leading to the acidification of freshwaters, as well as contamination by heavy metals. The ability of humic substances (HS) such as humic acid (HA) to decrease toxicity of heavy metals is widely known, whereas limited studies have examined the ability of HS to decrease toxicity linked with multiple stressors such as those associated with AMD. This study investigated the ability of HA to decrease acute toxicity defined as morbidity and ventilation frequency (measured via the time elapsed for ten operculum movements) in eastern rainbowfish (Melanotaenia splendida splendida) exposed to the multiple stressors of AMD-driven heavy metal concentrations, together with low pH. Water from the Mount Morgan open pit (a now closed gold and copper mine site), located at Mount Morgan, Central Queensland, Australia, was used as the AMD source. Fish were exposed to zero per cent (pH 7.3), two per cent (pH 6.7), three per cent (pH 5.7) and four per cent (pH 4.6) AMD in the presence of 0, 10 and 20mg/L Aldrich Humic Acid (AHA) over 96h. HA was shown to significantly decrease the acute toxicity of AMD and its adverse effects on ventilation frequency. These results are important in showing that HA can influence toxicity of metal mixtures and low pH, thus indicating a potential role for HA in decreasing toxicity of multiple environmental stressors more widely, and possible value as a rehabilitation aid. PMID:25173849

  3. IMPACT OF ADDITIONALS CONTAMINANTS DUE TO ACID MINE DRAINAGE IN TRIBUTARIES OF THE PILCOMAYO RIVER FROM CERRO RICO, POTOSÍ, BOLIVIA

    William H.J. Strosnider

    2014-09-01

    Full Text Available Intensive mining and processing of the polymetallic sulfide ore body of Cerro Rico de Potosí (Bolivia has occurred since 1545. To further investigate acid mine drainage (AMD discharges and their link to downstream contamination, data were gathered during two sampling events during the most extreme periods of the dry and wet seasons of one year. Concentrations of Ag, B, Ba, Mo, Sb, Se, Sn and V in AMD and receiving streams were greater than Bolivian discharge limits and receiving water body guidelines as well as international agricultural use standards. High concentrations of rare earth metals have been documented in this area. Results indicate that contamination from mining has a larger scope than previously thought and underscore the importance of remediation.

  4. Assessment of acid mine drainage remediation schemes on ground water flow regimes at a reclaimed mine site

    Ground water modeling and a field monitoring program were conducted for a 35-acre reclaimed surface mine site that continues to produce acid mine drainage (AMD). The modeling effort was focused on predicting the effectiveness of various remedial measures implemented at the site for the abatement of AMD on predicting the effectiveness of various remedial measures implemented at the site for the abatement of AMD production. The field work included surface surveys and monitoring of ground water levels with time, seepage areas, and sedimentation ponds located on the site. The surveys provided the physical and topographic characteristics of the site. Pump tests conducted at the site provided general hydraulic conductivities (k) for two major areas of the site; undisturbed area (k ≅ 2.9 x 10-5 ft/s) and disturbed area (k ≅ 3.3 x 10-4 ft/s to 2.0 x 10-3 ft/s). The monitored ground water data indicated rapid change in ground water levels during recharge events. Such behavior is indicative of flow regime that is dominated by fracture flow. Modeling of an approximately 700 ft by 1,500 ft area of the site was achieved using the US GS code MODFLOW, and ground water field measurements were used to calibrate the model. A hydraulic conductivity of about 1.15 x 10-3 ft/s was estimated for the undisturbed area and 1.15 x 10-2 ft/s for the reclaimed area. Remedial measures for diverting the ground water away from the areas of spoil included the use of a subsurface seepage cutoff wall and discrete sealing techniques. Modeling results indicated that the most effective remedial technique for this site is the use of a subsurface seepage cutoff wall installed at the interface (highwall) between the disturbed and undisturbed zones. Using this scheme caused a dewatering effect in the reclaimed area and therefore reduction in the volume of the AMD generated at the site

  5. Metals in agricultural produce associated with acid-mine drainage in Mount Morgan (Queensland, Australia).

    Vicente-Beckett, Victoria A; McCauley, Gaylene J Taylor; Duivenvoorden, Leo J

    2016-06-01

    Acid-mine drainage (AMD) into the Dee River from the historic gold and copper mine in Mount Morgan, Queensland (Australia) has been of concern to farmers in the area since 1925. This study sought to determine the levels of AMD-related metals and sulfur in agricultural produce grown near the mine-impacted Dee River, compare these with similar produce grown in reference fields (which had no known AMD influence), and assess any potential health risk using relevant Australian or US guidelines. Analyses of lucerne (Medicago sativa; also known as alfalfa) from five Dee fields showed the following average concentrations (mg/kg dry basis): Cd AMD influence; the levels were within the US National Research Council (US NRC) guidelines for maximum tolerable cattle dietary intake. Pasture grass (also cattle feed) from two fields in the Dee River floodplains gave mean concentrations (mg/kg dry) of Cd 0.14, Cu 12, Fe 313, Mn 111, Pb 1.4, Zn 86 and S 2450. All metal levels from the Dee and from reference sites were below the US NRC guidelines for maximum tolerable cattle dietary intake; however, the average Cd, Cu and Fe levels in Dee samples were significantly greater than the corresponding levels in the pasture grass reference sites, suggesting AMD influence in the Dee samples. The average levels in the edible portions of mandarin oranges (Citrus reticulata) from Dee sites (mg/kg wet weight) were Cd 0.011, Cu 0.59, Fe 2.2, Mn 0.56, Pb 0.18, S 91 and Zn 0.96. Cd and Zn were less than or close to, average Fe and Mn levels were at most twice, Cd 1.8 or 6.5 times, and Pb 8.5 or 72 times the maximum levels in raw oranges reported in the US total diet study (TDS) or the Australian TDS, respectively. Average Cd, Fe, Mn, Pb and Zn levels in the citrus reference samples were found to exceed the maximum reported in one or both TDS surveys. Cu, Fe, Mn, Pb and Zn plant-soil transfer factor (TF) values were < 1 for all agricultural samples from both Dee and reference sites, suggesting

  6. The Impact of Microbial Communities on Water Quality in an Acid Mine Drainage Impacted Watershed

    McDaniel, G. R.; Rademacher, L. K.; Faul, K. L.; Brunell, M.; Burmeister, K. C.

    2011-12-01

    Acid mine drainage (AMD) from the former Leona Heights Sulfur mine in Oakland, CA, contributes toxic levels of Cu, Cd, and Zn and elevated levels of Fe2+ and SO42- to downstream reaches of Lion Creek via Leona Creek. To investigate the extent of AMD and its relationship to microbial community structure, water samples were collected from three tributaries (two natural, and one with AMD) as well as the inlet and outlet of Lake Aliso (a reservoir downstream of the confluence of the three tributaries) beginning in July 2009. Lake Aliso was dammed in the late 1800s but since the early 1990s it has been full during the dry season and drained during the wet season, thus dramatically altering the geochemical conditions on a seasonal basis. Natural waters from Lion Creek and Horseshoe Creek tributaries dilute the water from Leona Creek, thus reducing concentrations of major ions and metals below toxic levels before water discharges into Lake Aliso. Precipitation events lead to episodes of increased mobilization of Cu and Cd in Leona Creek and produce toxic levels of these metals below the confluence with Lion Creek. Tributary mixing calculations suggest that even though Leona Creek contributes the smallest volume of water of the three tributaries, it is the main source of metals entering Lake Aliso. The input of the metal-rich AMD from Leona Creek changes the redox conditions of Lion Creek. In addition, Lake Aliso has a significant impact on water quality in the Lion Creek watershed. Observations of temperature, conductivity, pH, and dissolved oxygen in lake depth profiles indicate that Lake Aliso is stratified during the dry season when the lake is full. Based on concentration differences between the inlet and outlet of the lake, Na, Mg, SO42-, Ca, Mn, Zn, Cd, Cu and Ni are removed from the water while K, As, Pb and Fe are mobilized when Lake Aliso is full. Geochemical modeling using PhreeqcI suggests the deposition of minerals containing the metals that are being removed

  7. Development and Implementation of Integrative Bioassessment Techniques to Delineate Small Order Acid Mine Drainage Impacted Streams of the North Fork Powell River, Southwestern Virginia.

    Schmidt, Travis Scott

    2001-01-01

    Acid mine drainage (AMD) results from the oxidation of pyretic mineralogy, exposed by mining operations to oxygen and water. This reaction produces sulfuric acid and liberates heavy metals from the surrounding mineralogy and impairs water quality and freshwater communities. The U.S. Army Corps of Engineers has begun an ecosystem restoration project to remediate the abandoned mine land (AML) impacts to the North Fork Powell River (NFP) and is utilizing the ecotoxicological ratin...

  8. Distribution, ecology and inhibition of Thiobacillus ferrooxidans in relation to acid drainage from Witwatersrand gold mine dumps

    The distribution and ecology of Thiobacillus ferrooxidans in gold mine dumps and possible means for its inhibition were investigated. A literature survey of the micro-ecology of mine waste dumps in various parts of the world was undertaken. A linear alkylbenzene sulphonate (LAS), NANSA 80/S, and a cetyl pyridinium chloride, Ceepryn, were tested as possible inhibitors for mine dump application. The LAS was rejected because it is poorly soluble in water and required higher concentrations than SLS for the inhibition of T.ferrooxidans. Ceepryn was an efficient inhibitor, but its efficiency was dramatically impeded in the presence of mine dump sand making it unsuitable for application on dumps. The SLS and LAS were tested against a mixed population of T.ferrooxidans from gold mine dumps and these bacteria were shown to be marginally more resistant to the inhibitors than the pure T.ferrooxidans culture. Sampling from mine dumps on the Witwatersrand suggested that the major T.ferrooxidans populations occurred in the moist sand of the drainage areas at the base of dumps, with few viable iron-oxidising bacteria located on the surfaces or in the centre of dumps. Sites of low moisture in dumps contained few or no viable bacteria. In the laboratory the bacterial viability decreased rapidly with loss of moisture from the sand. Moisture was shown to be important to bacterial activity and should be considered with respect to acid drainage control. Experimental sand columns showed that iron was leached with water from mine dump sand in the absence and presence of bacteria. In this study substrates, moisture, oxygen and carbon dioxide availability, ph, temperature, microorganisms and metal pollutants of uranium waste dumps are also covered

  9. Ecological assessment of coal mine and metal mine drainage in South Korea using Daphnia magna bioassay

    Lee, Sang-Ho; Kim, Injeong; Kim, Kyoung-Woong; Lee, Byung-Tae

    2015-01-01

    In order to assess the ecological effect of acid mine drainage, metal mine (Dalsung) and coal mine (Samtan) drainage in South Korea were collected. The each mine drainage then investigated by whole effluent toxicity test (WET) and toxicity identification evaluation (TIE). WET results demonstrated that DS leachate and ST mine water is more toxic than other mine drainage due to the presence of cationic metals and acidic pH. TIE results revealed that the acidic pH and copper (Cu) could be the ma...

  10. Using a mass balance to understand the geology and geochemistry of a reservoir receiving and discharging acid mine drainage

    Howard-Williams Lake is a 14.5 acre reservoir located in an abandoned coal mine in Perry County, Ohio. With a pH of 3.0 and acidity values of 300--400 mg/L, the reservoir has no plants or fish currently surviving in the lake. Reclamation of spoil piles adjacent to the lake to the north in the late 1980s was not successful in reducing the acidity of the lake. Currently, papermill sludge is being used on the reclaimed area to the north to promote vegetation, but the reservoir has shown no signs of improving. The goal of this project is to transform the lake into a fishable and swimmable one. The reservoir is receiving about 175 gallons per minute of acid mine drainage, not including seepage into the lake, from eight different sources. Three of the sources account for about 165 gallons per minute of the surface water that enters the lake. These inflows have relatively low acidity readings, which range from 66 mg/L to 568 mg/L. The other five sources of acid mine drainage have much lower flowrates, but have acidity values as high as 3,000 mg/L. Samples of all of the surface inflows and the outflow of the lake were taken and sent to a laboratory and tested for the following parameters: total acidity as CaCO3, total alkalinity as CaCO2, specific conductivity, total suspended solids, sulfate, chloride calcium, magnesium, sodium, potassium, total iron, total manganese, aluminum, and hardness. During sampling of the surface inflows, volumetric flowrates were measured for each inflow. Once the flowrates and the concentrations of the various parameters were known, a mass balance could be constructed which would show how much of each parameter was entering the lake each day. These data were then used to gain an understanding of the geochemistry and geology of the site

  11. Effects of acid mine drainage on dissolved inorganic carbon and stable carbon isotopes in receiving streams

    Dissolved inorganic carbon (DIC) constitutes a significant fraction of a stream's carbon budget, yet the role of acid mine drainage (AMD) in DIC dynamics in receiving streams remains poorly understood. The objective of this study was to evaluate spatial and temporal effects of AMD and its chemical evolution on DIC and stable isotope ratio of DIC (δ13CDIC) in receiving streams. We examined spatial and seasonal variations in physical and chemical parameters, DIC, and δ13CDIC in a stream receiving AMD. In addition, we mixed different proportions of AMD and tap water in a laboratory experiment to investigate AMD dilution and variable bicarbonate concentrations to simulate downstream and seasonal hydrologic conditions in the stream. Field and laboratory samples showed variable pH, overall decreases in Fe2+, alkalinity, and DIC, and variable increase in δ13CDIC. We attribute the decrease in alkalinity, DIC loss, and enrichment of 13C of DIC in stream water to protons produced from oxidation of Fe2+ followed by Fe3+ hydrolysis and precipitation of Fe(OH)3(s). The extent of DIC decrease and 13C enrichment of DIC was related to the amount of HCO3- dehydrated by protons. The laboratory experiment showed that lower 13C enrichment occurred in unmixed AMD (2.7 per mille ) when the amount of protons produced was in excess of HCO3- or in tap water (3.2 per mille ) where no protons were produced from Fe3+ hydrolysis for HCO3- dehydration. The 13C enrichment increased and was highest for AMD-tap water mixture (8.0 per mille ) where Fe2+ was proportional to HCO3- concentration. Thus, the variable downstream and seasonal 13C enrichment in stream water was due in part to: (1) variations in the volume of stream water initially mixed with AMD and (2) to HCO3- input from groundwater and seepage in the downstream direction. Protons produced during the chemical evolution of AMD caused seasonal losses of 50 to >98% of stream water DIC. This loss of DIC in AMD impacted streams may have

  12. Mycogenic Mn(II) oxidation promotes remediation of acid mine drainage and other anthropogenically impacted environments

    Santelli, C. M.; Chaput, D.; Hansel, C. M.; Burgos, W. D.

    2014-12-01

    Manganese is a pollutant in worldwide environments contaminated with metals and organics, such as acid mine drainage (AMD), freshwater ponds, and agricultural waste storage sites. Microorganisms contribute to the removal of dissolved Mn compounds in the environment by promoting Mn(II) oxidation reactions. The oxidation of Mn(II) results in the precipitation of sparingly soluble Mn(IV) oxide minerals, effectively removing the metal from the aqueous milieu (e.g., groundwater or wastewater streams). In recent years, our research has identified a diversity of Mn(II)-oxidizing fungi inhabiting these polluted environments, however their overall contribution to the remediation process in situ remains poorly understood. Here we present results of culture-based and Next Generation Sequencing (NGS) studies in AMD treatment systems actively remediating Mn and other metals where we profile the bacterial, fungal, algal and archaeal communities to determine the overall community diversity and to establish the relative abundance of known Mn(II) oxidizers. A variety of treatment systems with varying Mn-removal efficiencies were sampled to understand the relationship between remediation efficiency and microbial community composition and activity. Targeted-amplicon sequencing of DNA and RNA of the 16S rRNA genes (bacteria and archaea), 23S rRNA genes (algae) and ITS region (fungi) was performed using both 454 pyrosequencing and Illumina platforms. Results showed that only the fungal taxonomic profiles significantly differed between sites that removed the majority of influent Mn and those that did not. Specifically, Ascomycota (which include known Mn(II) oxidizers isolated from these treatment systems) dominated greater efficiency systems whereas less efficient systems were dominated by Basidiomycota. Furthermore, known Mn(II) oxidizers accounted for only a minor proportion of bacterial sequences but a far greater proportion of fungal sequences. These culture-independent studies lend

  13. ACID ROCK DRAINAGE

    Anca Ionce

    2010-10-01

    Full Text Available Acid rock drainage (ARD is an particularly important aspect for the evaluation of the decantation ponds’ safety, and which has been only once taken into consideration at the Tarnicioara decantation pond, year 2002, as a consequence of the apparition of a strong seepage on the deposit’s dump, that has chemically de-purified the water from the river Brateasa. We have observed ARD, which implies the release of acid solutions from the mining sterile deposits, from the underground mining works and from the quarries, in the following tailings dams: Tarnicioara, Valea Strajii, Poarta Veche- which served Tarniţa Preparation Enterprise and in the Dealu Negru and Paraul Cailor ponds- which, at their time served Fundu Moldovei Preparation Enterprise, both during the period of their functioning and the period after their closure. For the decantation pond Dumitrelu which served the Calimani preparation enterprise, acid seepages from the deposit were mentioned in a study made by SC ICPM SA Baia Mare in 1993. Subsequently to the closure of the objective such seepage did not take place anymore. Instead, by raining, there is a frequent plant sterile dragging from the contour retaining wall down to the trouble pond, situated upstream.

  14. Ecological assessment of coal mine and metal mine drainage in South Korea using Daphnia magna bioassay.

    Lee, Sang-Ho; Kim, Injeong; Kim, Kyoung-Woong; Lee, Byung-Tae

    2015-01-01

    In order to assess the ecological effect of acid mine drainage, metal mine (Dalsung) and coal mine (Samtan) drainage in South Korea were collected. The each mine drainage then investigated by whole effluent toxicity test (WET) and toxicity identification evaluation (TIE). WET results demonstrated that DS leachate and ST mine water is more toxic than other mine drainage due to the presence of cationic metals and acidic pH. TIE results revealed that the acidic pH and copper (Cu) could be the main toxicants in both mine drainage. The strong acidic pH (pH toxicity by increase of metal activity and bioavailability. The toxicity of most mine drainage revealed that the positive correlation between metal concentration and toxicity unit (TU). The regression data between TU and sum of cumulative criterion unit (CCU) demonstrated the reasonable statistical significance (R = 0.89; p toxicity by the effect of amorphous iron precipitate. PMID:26405638

  15. Role of dissimilatory sulfate reduction in wetlands constructed for acid coal mine drainage (AMD) treatment. Master's thesis

    Five constructed wetlands with different organic substrates were exposed to the same quantity/quality of acid mine drainage (AMD). During the 16-month exposure to AMD, all wetlands accumulated S in the forms of organic and reduced inorganic S and Fe in the form of iron sulfides. Iron sulfide and probably most of the organic S(C-bonded S) accumulation were end products of bacterial dissimilatory sulfate reduction. Results of study support the notion that sulfate reduction and accumulation of Fe sulfides contribute to Fe retention in wetlands exposed to AMD. Detailed information is provided

  16. Quantifying heavy metals sequestration by sulfate-reducing bacteria in an acid mine drainage-contaminated wetland

    JohnWMoreau

    2013-03-01

    Full Text Available Bioremediation strategies that depend on bacterial sulfate reduction for heavy metals remediation harness the reactivity of these metals with biogenic aqueous sulfide. Quantitative knowledge of the degree to which specific toxic metals are partitioned into various sulfide, oxide, or other phases is important for predicting the long-term mobility of these metals under environmental conditions. Here we report the quantitative partitioning into sedimentary biogenic sulfides of a suite of metals and metalloids associated with acid mine drainage contamination of a natural estuarine wetland for over a century.

  17. Fundamental study of a one-step ambient temperature ferrite process for treatment of acid mine drainage waters

    Morgan, B. E.; Loewenthal, R. E.; Lahav, O.

    2001-01-01

    A novel approach towards the removal of iron and heavy metals from South African acid mine drainage (AMD) waters is presented. The approach involves the controlled oxidation of ferrous-containing AMD water at ambient temperatures in the presence of magnetite seed. The resulting oxidation product is the ferrite (Ml(2)(3+)M2(2+)O(4)) magnetite (Fe3O4), which has the capacity for non-ferrous metal removal, and which forms a stable sludge that is easily separated from the effluent. Sludge charact...

  18. Acid Mine Drainage Research in Gauteng Highlighting Impacts on Infrastructure and Innovation of Concrete-Based Remedial Systems

    Diop, S.; Ekolu, S.; Azene, F.

    2013-12-01

    Acid mine drainage (AMD) is presently one of the most important environmental problems in in the densely populated Gauteng Province, South Africa. The threat of acid mine drainage has demanded short-term interventions (some of which are being implemented by government) but more importantly sustainable long-term innovative solutions. There have been moments of public apprehension with some media reports dubbing the current scenario as a future 'nightmare of biblical proportions' and 'South Africa's own Chernobyl' that could cause dissolving of concrete foundations of buildings and reinforcement steel, leading to collapse of structures. In response to the needs of local and provincial authorities, this research was conducted to (1) generate scientific understanding of the effects of AMD on infrastructure materials and structures, and (2) propose innovative long-term remedial systems based on cementitious materials for potential AMD treatment applications of engineering scale. Two AMD solutions from the goldfields and two others from the coalfields were used to conduct corrosion immersion tests on mild steel, stainless steel, mortars, pastes and concretes. Results show that AMD water from the gold mines is more corrosive than that from the coal mines, the corrosion rate of the former being about twice that of the latter. The functionality of metal components of mild steel can be expected to fail within one month of exposure to the mine water. The investigation has also led to development of a pervious concrete filter system of water-cement ratio = 0.27 and cement content = 360 kg/m3, to be used as a permeable reactive barrier for AMD treatment. Early results show that the system was effective in removing heavy metal contaminants with removal levels of 30% SO4, 99% Fe, 50-83% Mn, 85% Ca, and 30% TDS. Further work is on-going to improve and optimise the system prior to field demonstration studies.

  19. SODA ASH TREATMENT OF NEUTRALIZED MINE DRAINAGE

    Utilization of acid mine drainage (AMD) streams as a source of potable and industrial water has become a major goal of several proposed AMD treatment schemes. From among the various schemes available, the lime neutralization/soda ash softening process was selected for use at Alto...

  20. Acid Mine Drainage Passive Remediation: Potential Use of Alkaline Clay, Optimal Mixing Ratio and Long Term Impacts

    Plaza, F.; Liang, X.; Wen, Y.; Perone, H.

    2015-12-01

    Acid mine drainage (AMD) is one of the most adverse environmental problems of the mine industry. Surface water and ground water affected by this pollution are characterized by their acidity and the high content of sulfates and heavy metals. In this study, alkaline clay, an industrial waste with a high pH, which is utilized in the alumina refining process, was used as the remediation material to inhibit pyrite oxidation. Through a series of batch and column experiments, complemented with field measurements and geochemical modeling, three important issues associated with this passive and auto sustainable acid mine drainage remediation method were investigated: 1) the potential use of alkaline clay as an AMD remediation material, 2) the adequate alkaline clay/coal refuse mixing ratio (AC/CR) to ensure pH values near to neutral conditions, and, 3) the prediction of long term impacts, in terms of the trends of the main parameters involved in this process such as pH, concentrations of sulfate, iron and other dissolved contaminants. Both field measurements and the samples used for the experiments came from a coal waste site located in Mather, Pennsylvania. Alkaline clay proved to be an effective remediation material for AMD. It was found that 10% AC/CR is an adequate mixing ratio (i.e. the upper limit), which has been also indicated by field measurements. The concentrations of some contaminants such as iron, manganese or sulfate are significantly reduced with the remediation approach, compared to those representative concentrations found in mine tailings. Moreover, results suggest a very reliable long-term stability of the remediation (i.e. neutral pH conditions are maintained), thus enhancing the generation of iron precipitates that could produce pyrite grain coating and hardpan (i.e. cemented layer) on the surface. These processes also made the amended layer less porous, thus increasing water retention and hindering oxygen diffusion.

  1. Comparison of limestone, dolomite and fly ash as pre-treatment agents for acid mine drainage

    Potgieter-Vermaak, S.S.; Potgieter, J.H.; Monama, P.; Van Grieken, R. [Tshwane University of Technology, Pretoria (South Africa). Dept. of Chemistry

    2006-04-15

    The physical, chemical and biological nature of Vaal Dam water, the main source of water in Gauteng, South Africa, is often affected by underground water pollution (acid mine water) and industrial effluents. The ecological significance and detrimental effects necessitate investigations into treating the water prior to discharge into public streams. In this investigation, limestone, dolomite and fly ash were selected as pre-treatment agents based on their low cost. Simulated acid mine water containing these agents was tested using a Jar Test apparatus. Samples were analyzed before and after treatment for pH, ferrous, ferric, calcium, magnesium and sulphate ions. The study demonstrated that the quality of the water improved with an increase in the amount and surface area of the raw material dosed and an increase in contact time. It was also influenced by the chemical composition of the acid mine water and aeration. Chemical cost savings of 38% are achieved when lime is replaced with limestone, and cost savings of 23% and 48% can be accomplished when limestone is substituted with dolomite and fly ash respectively. This could result in significant savings to the gold and coal mining industries, and could lead to a mutual benefit/gain between industrialists/polluters and the public.

  2. Benthic Communities of Low-Order Streams Affected by Acid Mine Drainages: A Case Study from Central Europe

    Marek Svitok

    2014-05-01

    Full Text Available Only little attention has been paid to the impact of acid mine drainages (AMD on aquatic ecosystems in Central Europe. In this study, we investigate the physico-chemical properties of low-order streams and the response of benthic invertebrates to AMD pollution in the Banská Štiavnica mining region (Slovakia. The studied streams showed typical signs of mine drainage pollution: higher conductivity, elevated iron, aluminum, zinc and copper loads and accumulations of ferric precipitates. Electric conductivity correlated strongly with most of the investigated elements (weighted mean absolute correlation = 0.95 and, therefore, can be recommended as a good proxy indicator for rapid AMD pollution assessments. The diversity and composition of invertebrate assemblages was related to water chemistry. Taxa richness decreased significantly along an AMD-intensity gradient. While moderately affected sites supported relatively rich assemblages, the harshest environmental conditions (pH < 2.5 were typical for the presence of a limited number of very tolerant taxa, such as Oligochaeta and some Diptera (Limnophyes, Forcipomyiinae. The trophic guild structure correlated significantly with AMD chemistry, whereby predators completely disappeared under the most severe AMD conditions. We also provide a brief review of the AMD literature and outline the needs for future detailed studies involving functional descriptors of the impact of AMD on aquatic ecosystems.

  3. Organic substrates as electron donors in permeable reactive barriers for removal of heavy metals from acid mine drainage.

    Kijjanapanich, P; Pakdeerattanamint, K; Lens, P N L; Annachhatre, A P

    2012-12-01

    This research was conducted to select suitable natural organic substrates as potential carbon sources for use as electron donors for biological sulphate reduction in a permeable reactive barrier (PRB). A number of organic substrates were assessed through batch and continuous column experiments under anaerobic conditions with acid mine drainage (AMD) obtained from an abandoned lignite coal mine. To keep the heavy metal concentration at a constant level, the AMD was supplemented with heavy metals whenever necessary. Under anaerobic conditions, sulphate-reducing bacteria (SRB) converted sulphate into sulphide using the organic substrates as electron donors. The sulphide that was generated precipitated heavy metals as metal sulphides. Organic substrates, which yielded the highest sulphate reduction in batch tests, were selected for continuous column experiments which lasted over 200 days. A mixture of pig-farm wastewater treatment sludge, rice husk and coconut husk chips yielded the best heavy metal (Fe, Cu, Zn and Mn) removal efficiencies of over 90%. PMID:23437664

  4. Diversity and Distribution of Arsenic-Related Genes Along a Pollution Gradient in a River Affected by Acid Mine Drainage.

    Desoeuvre, Angélique; Casiot, Corinne; Héry, Marina

    2016-04-01

    Some microorganisms have the capacity to interact with arsenic through resistance or metabolic processes. Their activities contribute to the fate of arsenic in contaminated ecosystems. To investigate the genetic potential involved in these interactions in a zone of confluence between a pristine river and an arsenic-rich acid mine drainage, we explored the diversity of marker genes for arsenic resistance (arsB, acr3.1, acr3.2), methylation (arsM), and respiration (arrA) in waters characterized by contrasted concentrations of metallic elements (including arsenic) and pH. While arsB-carrying bacteria were representative of pristine waters, Acr3 proteins may confer to generalist bacteria the capacity to cope with an increase of contamination. arsM showed an unexpected wide distribution, suggesting biomethylation may impact arsenic fate in contaminated aquatic ecosystems. arrA gene survey suggested that only specialist microorganisms (adapted to moderately or extremely contaminated environments) have the capacity to respire arsenate. Their distribution, modulated by water chemistry, attested the specialist nature of the arsenate respirers. This is the first report of the impact of an acid mine drainage on the diversity and distribution of arsenic (As)-related genes in river waters. The fate of arsenic in this ecosystem is probably under the influence of the abundance and activity of specific microbial populations involved in different As biotransformations. PMID:26603631

  5. Leaf Associated Microbial Activities in a Stream Affected by Acid Mine Drainage

    Schlief, Jeanette

    2004-11-01

    Microbial activity was assessed on birch leaves and plastic strips during 140 days of exposure at three sites in an acidic stream of the Lusatian post-mining landscape, Germany. The sites differed in their degrees of ochre deposition and acidification. The aim of the study was (1) to follow the microbial activities during leaf colonization, (2) to compare the effect of different environmental conditions on leaf associated microbial activities, and (3) to test the microbial availability of leaf litter in acidic mining waters. The activity peaked after 49 days and subsequently decreased gradually at all sites. A formation of iron plaques on leaf surfaces influenced associated microbial activity. It seemed that these plaques inhibit the microbial availability of leaf litter and serve as a microbial habitat by itself. (

  6. Immobilization of Arsenite and Ferric Iron by Acidithiobacillus ferrooxidans and Its Relevance to Acid Mine Drainage

    Duquesne, K.; Lebrun, S.; Casiot, C.; Bruneel, O.; Personné, J.-C.; LeBlanc, M.; Elbaz-Poulichet, F.; Morin, G.; Bonnefoy, V.

    2003-01-01

    Weathering of the As-rich pyrite-rich tailings of the abandoned mining site of Carnoulès (southeastern France) results in the formation of acid waters heavily loaded with arsenic. Dissolved arsenic present in the seepage waters precipitates within a few meters from the bottom of the tailing dam in the presence of microorganisms. An Acidithiobacillus ferrooxidans strain, referred to as CC1, was isolated from the effluents. This strain was able to remove arsenic from a defined synthetic medium ...

  7. Diversity and spatiotemporal dynamics of bacterial communities : physicochemical and other drivers along an acid mine drainage

    Volant, A; Bruneel, Odile; Desoeuvre, A.; Hery, M; Casiot, C.; Bru, N.; Delpoux, S.; Fahy, A.; Javerliat, F.; Bouchez, O.; Duran, R.; Bertin, P. N.; Elbaz-Poulichet, F.; Lauga, B.

    2014-01-01

    Deciphering the biotic and abiotic factors that control microbial community structure over time and along an environmental gradient is a pivotal question in microbial ecology. Carnoules mine (France), which is characterized by acid waters and very high concentrations of arsenic, iron, and sulfate, provides an excellent opportunity to study these factors along the pollution gradient of Reigous Creek. To this end, biodiversity and spatiotemporal distribution of bacterial communities were charac...

  8. Characterization of water reservoirs affected by acid mine drainage: geochemical, mineralogical, and biological (diatoms) properties of the water.

    Valente, T; Rivera, M J; Almeida, S F P; Delgado, C; Gomes, P; Grande, J A; de la Torre, M L; Santisteban, M

    2016-04-01

    This work presents a combination of geochemical, mineralogical, and biological data obtained in water reservoirs located in one of the most paradigmatic mining regions, suffering from acid mine drainage (AMD) problems: the Iberian Pyrite Belt (IPB). Four water reservoirs located in the Spanish sector of the IBP, storing water for different purposes, were selected to achieve an environmental classification based on the effects of AMD: two mining dams (Gossan and Águas Ácidas), a reservoir for industrial use (Sancho), and one with water used for human supply (Andévalo). The results indicated that the four reservoirs are subject to the effect of metallic loads from polluted rivers, although with different levels: Águas Ácidas > Gossan > Sancho ≥ Andévalo. In accordance, epipsammic diatom communities have differences in the respective composition and dominant taxa. The dominant diatoms in each reservoir indicated acid water: Pinnularia acidophila and Pinnularia aljustrelica were found in the most acidic dams (Gossan and Águas Ácidas, with pH <3), Pinnularia subcapitata in Sancho (pH 2.48-5.82), and Eunotia exigua in Andévalo (pH 2.34-6.15). PMID:26032451

  9. Spatial and Temporal Analysis of the Microbial Community in the Tailings of a Pb-Zn Mine Generating Acidic Drainage ▿ †

    Huang, Li-Nan; Zhou, Wen-Hua; Hallberg, Kevin B.; Wan, Cai-Yun; Li, Jie; Shu, Wen-Sheng

    2011-01-01

    Analysis of spatial and temporal variations in the microbial community in the abandoned tailings impoundment of a Pb-Zn mine revealed distinct microbial populations associated with the different oxidation stages of the tailings. Although Acidithiobacillus ferrooxidans and Leptospirillum spp. were consistently present in the acidic tailings, acidophilic archaea, mostly Ferroplasma acidiphilum, were predominant in the oxidized zones and the oxidation front, indicating their importance to generation of acid mine drainage. PMID:21705549

  10. Spatio-Temporal Detection of the Thiomonas Population and the Thiomonas Arsenite Oxidase Involved in Natural Arsenite Attenuation Processes in the Carnoulès Acid Mine Drainage

    Hovasse, Agnès; Bruneel, Odile; Casiot, Corinne; Desoeuvre, Angélique; Farasin, Julien; Hery, Marina; Van Dorsselaer, Alain; Carapito, Christine; Arsène-Ploetze, Florence

    2016-01-01

    The acid mine drainage (AMD) impacted creek of the Carnoulès mine (Southern France) is characterized by acid waters with a high heavy metal content. The microbial community inhabiting this AMD was extensively studied using isolation, metagenomic and metaproteomic methods, and the results showed that a natural arsenic (and iron) attenuation process involving the arsenite oxidase activity of several Thiomonas strains occurs at this site. A sensitive quantitative Selected Reaction Monitoring (SR...

  11. Biosorption of Fe, Al and Mn of acid drainage from coal mine using brown seaweed sargassum sp. in continuous process

    The acid mine drainage (AMD) are leaches as result of a coal mining running, it have low ph and high concentrations of heavy metals that convert them in strong polluter; with the purpose of reduce its concentration, a continuous biosorption system was designed by removing heavy metals from drainages using a cheap biosorbent material. The brown seaweed was pre-treatment with solutions 0,1 N of NaOH, Ca(OH)2 NaCl, CaCl2, NaSO4 y H2SO4 for to study the effect on biosorption process; the removal percentage were determined, which are better than 80% with the exception of pre-treatment with H2SO4 who cancel the algae sorption capacity. The seaweed was packed in plastic mesh and polyester tulle in the shape of a rectangular prism; there isn't effect on the biosorption process by using this packet. The continuous biosorption process was studied in two units of operation: a packed-bed flow-through sorption column and an horizontal vessel like a canal with baffles, which treated adequately 3,5 and 4,71 of AMD respectively, using in each one of them 100 g of algae. The burning of algae was studied like an alternative for the problem of handling of residual algae. The ashes kept the metals removed from AMD, furthermore keep stable too by the attack of solutions of different pH

  12. Use of man-made impoundment in mitigating acid mine drainage in the North Branch Potomac River

    The US Department of the Army, Baltimore District Corps of Engineers, oversees a long-term monitoring study to assess and evaluate effects of the Jennings-Randolph reservoir on biota in the North Branch Potomac River. The reservoir was intended, in part, to mitigate effects of acid mine drainage originating in upstream and headwater area. The present study assessed recovery of benthos and fish in this system, six years after completion of the reservoir. Higher pH and lower iron and sulfate concentrations were observed upstream of the reservoir compared to preimpoundment conditions, suggesting better overall water quality in the upper North Branch. Water quality improved slightly directly downstream of the reservoir. However, the reservoir itself was poorly colonized by macrophytes and benthic organisms, and plankton composition suggested either metal toxicity and/or nutrient limitation. One large tributary to the North Branch and the reservoir (Stony River) was shown to have high (and possibly toxic) levels of manganese, iron, zinc, and aluminum due to subsurface coal mine drainage. Macroinvertebrate diversity and number of taxa were higher in sites downstream of the reservoir in the present study. Compared with previous years, the present study suggested relatively rapid recovery in the lower North Branch due to colonization from two major unimpacted tributaries in this system: Savage River and South Branch Potomac. Fish data were consistent with macroinvertebrate results, but site-to-site variation in species composition was greater. Results show that recovery of biota in the North Branch Potomac was attributed to decreased acid inputs from mining operations and dilution from the Savage River, which contributed better water quality. Continued improvement of North Branch Potomac biota may not be expected unless additional mitigation attempts, either within the reservoir or upstream, are undertaken

  13. Hydrological modeling of a watershed affected by acid mine drainage (Odiel River, SW Spain). Assessment of the pollutant contributing areas

    Galván, L.; Olías, M.; Cánovas, C. R.; Sarmiento, A. M.; Nieto, J. M.

    2016-09-01

    The Odiel watershed drains materials belonging to the Iberian Pyrite Belt, where significant massive sulfide deposits have been mined historically. As a result, a huge amount of sulfide-rich wastes are deposited in the watershed, which suffer from oxidation, releasing acidic lixiviates with high sulfate and metal concentrations. In order to reliably estimate the metal loadings along the watershed a complete series of discharge and hydrochemical data are essential. A hydrological model was performed with SWAT (Soil and Water Assessment Tool) to solve the scarcity of gauge stations along the watershed. The model was calibrated and validated from daily discharge data (from 1980 to 2010) at the outlet of the watershed, river inputs into an existent reservoir, and a flow gauge station close to the northern area of the watershed. Discharge data obtained from the hydrological model, together with analytical data, allowed the estimation of the dissolved pollutant load delivered annually by the Odiel River (e.g. 9140 t of Al, 2760 t of Zn). The pollutant load is influenced strongly by the rainfall regime, and can even double during extremely rainy years. Around 50% of total pollution comes from the Riotinto Mining District, so the treatment of Riotinto lixiviates reaching the Odiel watershed would reduce the AMD (Acid Mine Drainages) in a remarkable way, improving the water quality downstream, especially in the reservoir of Alcolea, currently under construction. The information obtained in this study will allow the optimization of remediation efforts in the watershed, in order to improve its water quality.

  14. Removal of heavy metals from acid mine drainage (AMD) using coal fly ash, natural clinker and synthetic zeolites.

    Ríos, C A; Williams, C D; Roberts, C L

    2008-08-15

    Acid mine drainage (AMD) is a widespread environmental problem associated with both working and abandoned mining operations, resulting from the microbial oxidation of pyrite in presence of water and air, affording an acidic solution that contains toxic metal ions. The generation of AMD and release of dissolved heavy metals is an important concern facing the mining industry. The present study aimed at evaluating the use of low-cost sorbents like coal fly ash, natural clinker and synthetic zeolites to clean-up AMD generated at the Parys Mountain copper-lead-zinc deposit, Anglesey (North Wales), and to remove heavy metals and ammonium from AMD. pH played a very important role in the sorption/removal of the contaminants and a higher adsorbent ratio in the treatment of AMD promoted the increase of the pH, particularly using natural clinker-based faujasite (7.70-9.43) and the reduction of metal concentration. Na-phillipsite showed a lower efficiency as compared to that of faujasite. Selectivity of faujasite for metal removal was, in decreasing order, Fe>As>Pb>Zn>Cu>Ni>Cr. Based on these results, the use of these materials has the potential to provide improved methods for the treatment of AMD. PMID:18221835

  15. Archaeal diversity in a Fe-As rich acid mine drainage at Carnoules (France)

    Bruneel, Odile; Pascault, N.; Egal, M; Bancon-Montigny, C.; Goni-urriza, M. S.; Elbaz Poulichet, F.; Personne, J. C.; Duran, R.

    2008-01-01

    The acid waters (pH = 2.73-3.4) that originate from the Carnoules mine tailings (France) are known for their very high concentrations of As (up to 10,000 mg l(-1)) and Fe (up to 20,000 mg l(-1)). To analyze the composition of the archaeal community, (their temporal variation inside the tailing and spatial variations all along the Reigous Creek, which drains the site), seven 16S rRNA gene libraries were constructed. Clone analysis revealed that all the sequences were affiliated to the phylum E...

  16. Occurrence, properties and pollution potential of environmental minerals in acid mine drainage.

    Valente, T Maria; Leal Gomes, C

    2009-01-15

    This paper describes the occurrences, the mineralogical assemblages and the environmental relevance of the AMD-precipitates from the abandoned mine of Valdarcas, Northern Portugal. At this mining site, these precipitates are particularly related with the chemical speciation of iron, which is in according to the abundance of mine wastes enriched in pyrrhotite and pyrite. The more relevant supergene mineralogical assemblages include the following environmental minerals: soluble metal-salts, mainly sulphates, revealing seasonal behaviour, iron-hydroxysulphates and iron-oxyhydroxides, both forming ochre precipitates of poorly and well-crystalline minerals. Pollution potential of the most highly water soluble salts was analysed in order to evaluate the environmental effect of their dissolution by rainfall. Laboratory experiments, carried out with iron and aluminium sulphates, demonstrated the facility to release metals, sulphate and acidity upon dissolution. Regarding the ochre precipitates, composed by several less soluble iron (III)-minerals, the spatial distribution on the nearby aqueous system as well as the proportion of Jarosite, Schwertmannite and Goethite in the mixtures gave information about the halo's contamination promoted by the AMD emerging from the waste-dumps. PMID:19004477

  17. Acid mine drainage prevention, control and treatment technology development for the Stockett/Sand Coulee area. Topical report, March 1, 1995 - March 31, 1996

    The project was initiated to assist the State of Montana to develop a methodology to ameliorate acid mine drainage problems associated with the abandoned mines located in the Stockett/Sand Coulee area near Great Falls, Montana. Extremely acidic water is continuously discharging from abandoned coal mines in the Stockett/Sand Coulee area at an estimated rate of greater than 600 acre-feet per year (about 350 to 400 gallons per minute). Due to its extreme acidity, the water is unusable and is contaminating other water supplies. Most of the local alluvial aquifers have been contaminated, and nearly 5% of the private wells that were tested in the area during the mid-1980's showed some degree of contamination. Significant government money has been spent replacing water supplies due to the magnitude of this problem. In addition, millions of dollars have been spent trying to remediate acid mine drainage occurring in this coal field. To date, the techniques used have focused on the management and containment of mine waters, rather than designing technologies that would prevent the formation of acid mine drainage

  18. Hydrogeochemical and mineralogical characteristics related to heavy metal attenuation in a stream polluted by acid mine drainage: a case study in Dabaoshan Mine, China.

    Zhao, Huarong; Xia, Beicheng; Qin, Jianqiao; Zhang, Jiaying

    2012-01-01

    Dabaoshan Mine, the largest mine in south China, has been developed since the 1970s. Acid mine drainage (AMD) discharged from the mine has caused severe environmental pollution and human health problems. In this article, chemical characteristics, mineralogy of ocher precipitations and heavy metal attenuation in the AMD are discussed based on physicochemical analysis, mineral analysis, sequential extraction experiments and hydrogeochemistry. The AMD chemical characteristics were determined from the initialwater composition, water-rock interactions and dissolved sulfide minerals in the mine tailings. The waters, affected and unaffected by AMD, were Ca-SO4 and Ca-HCO3 types, respectively. The affected water had a low pH, high SO4(2-) and high heavy metal content and oxidation as determined by the Fe2+/Fe3+ couple. Heavy metal and SO4(2-) contents of Hengshi River water decreased, while pH increased, downstream. Schwertmannite was the major mineral at the waste dump, while goethite and quartz were dominant at the tailings dam and streambed. Schwertmannite was transformed into goethite at the tailings dam and streambed. The sulfate ions of the secondary minerals changed from bidentate- to monodentate-complexes downstream. Fe-Mn oxide phases of Zn, Cd and Pb in sediments increased downstream. However, organic matter complexes of Cu in sediments increased further away from the tailings. Fe3+ mineral precipitates and transformations controlled the AMD water chemistry. PMID:23505864

  19. Acid mine drainage and its impact in the Black Creek watershed, Virginia

    A one-year study was conducted to determine the impacts of acid min drainage (AMD) on the Black Creek watershed in Wise County, Virginia. Water quality, metal content of sediment and water column, soil pH, macroinvertebrate assemblages, habitat assessment and toxicity testing were used to assess the impact in the watershed. A total of 22 sites in the creek and surrounding watershed were actively monitored. This included six primary sources of AMD. Conductivity measurements > 1,000 microhmos/cm were found at eight sites and pH was consistently below 6.0 at seven. Of six metals analyzed, magnesium was highest in the water column, ranging from 16.5 mg/L to 130 mg/L. Aluminum and iron were both elevated in the sediment with iron concentrations as high as 176,000 mg/kg. An increase in sediment metal concentrations was noted when progressing downstream in the creek. Of nine high wall and spoils areas sampled, soil pH was acidic in eight sites, ranging from 5.5 to 3.1. Macroinvertebrate assemblages and habitat assessment indicate that much of the creek is impacted by AMD or heavy siltation. Laboratory bioassays with Daphnia magna and Chironomus tentans have indicated both acute and chronic toxicity of water and sediment samples from selected sites within the creek. Potential recovery of the system is being addressed through a sediment purging study. Restoration options will be considered once the degree of impact is fully characterized

  20. Biomonitoring study of a constructed wetland site treating acid mine drainage. Research report, July 1990-June 1992

    Acid Mine Drainage (AMD) from an underground coal mine in the Jones Branch watershed in McCreary County, KY, substantially reduced water quality in Jones Branch. Downstream from the mine seeps, the pH was routinely below 4.5 and concentrations of most heavy metals, especially iron, were elevated. A cattail wetland (1,022 m2) was constructed on Jones Branch in 1989 to obviate the effects of the AMD. Monthly chemical monitoring was performed on the water from above, from below, and from the 26 cells within the wetland. Based on chemical monitoring, the wetland initially improved water quality, increasing the pH and removing substantial amounts of heavy metals. Beginning in the spring of 1991, water quality at the wetland outfall began to decline, and has not improved to date. To augment the chemical monitoring, a biomonitoring study was initiated in the spring of 1990. Acute 48-hr. static tests were conducted with newly hatched fathead minnows (Pimephales promelas). Median lethal concentration (LC50) values determined monthly reflects the decline in water quality at the outfall over time

  1. Monitoring the Extent of Contamination from Acid Mine Drainage in the Iberian Pyrite Belt (SW Spain Using Hyperspectral Imagery

    Asuncion Riaza

    2011-10-01

    Full Text Available Monitoring mine waste from sulfide deposits by hyperspectral remote sensing can be used to predict surface water quality by quantitatively estimating acid drainage and metal contamination on a yearly basis. In addition, analysis of the mineralogy of surface crusts rich in soluble salts can provide a record of annual humidity and temperature. In fact, temporal monitoring of salt efflorescence from mine wastes at a mine site in the Iberian Pyrite Belt (Huelva, Spain has been achieved using hyperspectral airborne Hymap data. Furthermore, climate variability estimates are possible based on oxidation stages derived from well-known sequences of minerals, by tracing sulfide oxidation intensity using archive spectral libraries. Thus, airborne and spaceborne hyperspectral remote sensing data can be used to provide a short-term record of climate change, and represent a useful set of tools for assessing environmental geoindicators in semi-arid areas. Spectral and geomorphological indicators can be monitored on a regular basis through image processing, supported by field and laboratory spectral data. In fact, hyperspectral image analysis is one of the methods selected by the Joint Research Centre of the European Community (Ispra, Italy to study abandoned mine sites, in order to assess the enforcement of the European Mine Waste Directive (2006/21/EC of the European Parliament and of the Council 15 March 2006 on the management of waste from extractive industries (Official Journal of the European Union, 11 April 2006. The pyrite belt in Andalucia has been selected as one of the core mission test sites for the PECOMINES II program (Cracow, November 2005, using imaging spectroscopy; and this technique is expected to be implemented as a monitoring tool by the Environmental Net of Andalucía (REDIAM, Junta de Andalucía, Spain.

  2. BIOREMEDIATION FOR ACID MINE DRAINAGE: ORGANIC SOLID WASTE AS CARBON SOURCES FOR SULFATE-REDUCING BACTERIA: A REVIEW

    I. N. Jamil

    2013-12-01

    Full Text Available Biological sulfate reduction has been slowly replacing chemical unit processes to treat acid mine drainage (AMD. Bioremediations for AMD treatment are favored due to their low capital and maintenance cost. This paper describes the available AMD treatment, current SRB commercialization such as THIOPAQ® and BioSulphide® technologies, and also the factors and limitations faced. THIOPAQ® and BioSulphide® technologies use expensive carbon sources such as hydrogen as the electron donor. This paper discusses the possibility of organic solid waste as an alternative substrate as it is cheaper and abundant. A possible AMD treatment system setup was also proposed to test the efficiency of sulfate-reducing bacteria utilizing organic solid substrate.

  3. Isotope geochemistry of waters affected by acid mine drainage in old labour sites (SE, Spain).

    Pérez-Sirvent, Carmen; Martinez-Sanchez, Maria Jose; Garcia-Lorenzo, Maria Luz; Agudo, Ines; Hernandez-Cordoba, Manuel; Recio, Clemente

    2015-04-01

    The ore deposits of this zone have iron, lead and zinc as the main metal components. Iron is present in oxides, hydroxides, sulfides, sulfates, carbonates, and silicates; lead and zinc occur in sulfides (galena and sphalerite, respectively), carbonates, sulfates, and lead or zinc-bearing (manganese, iron) oxides. Mining started with the Romans and activity peaked in the second half of the 19th century and throughout the 20th century until the 1980's. From 1940 to 1957, mineral concentration was made by froth flotation and, prior to this, by gravimetric techniques. The mining wastes, or tailings, with a very fine particle size were deposited inland (tailings dams) and, since 1957, huge releases were made in directly the sea coast. The objective of this work was to evaluate processes affecting waters from abandoned mine sites by way of stable isotopic analysis, particularly H and O stable isotopes from water and S and O from dissolved sulfates. Several common chemical and physical processes, such as evaporation, water-rock interaction and mixing could alter water isotopic composition. Evaporation, which causes an enrichment in δD and δ18O in the residual water, is an important process in semiarid areas. The results obtained indicate that, for sites near the coast, waters are meteoric, and marine infiltration only takes place in the deepest layers near the shore or if water remains stagnated in sediments with low permeability. The main source of sulfate was the oxidation of sulfides, resulting in the liberation of acid, sulfate and metals. In order to assess the mechanism responsible for sulfide oxidation, the stoichiometric isotope balance model and the general isotope balance model were tested, suggesting that the oxidation via Fe3+ was predominant in the surface, and controlled by A. ferrooxidans, while at depth, sulfate reduction occurred.

  4. Formation of hydroxyl radical (sm-bulletOH) in illuminated surface waters contaminated with acidic mine drainage

    Formation rates and steady-state concentrations of hydroxyl radical (sm-bulletOH) in illuminated surface water samples collected in west-central Indiana that receive acidic mine drainage runoff are reported. Formation rates for sm-bulletOH in samples were measured by the addition of 1 x 10-3 M benzene prior to illuminate in order to effectively scavenge all of the sm-bulletOH formed, thereby yielding phenol. The sm-bulletOH formation rates were calculated from the measured phenol formation rates. Steady-state concentrations of sm-bulletOH were measured by the addition of 5 x 10-7 M nitrobenzene to the samples prior to illumination. Estimated sunlight sm-bulletOH formation rates range from 16 microM h-1 to 265 microM h-1. Estimated sunlight steady-state sm-bulletOH concentrations range from 6.7 x 10-15 to 4.0 x 10-12 M. Both the formation rates and steady-state concentrations for sm-bulletOH are thus two to three orders of magnitude higher than values reported in the literature for other sunlit surface water samples. Due to the very high rates of formation and steady-state concentrations for sm-bulletOH in these samples, the authors conclude that aqueous-phase reactions involving sm-bulletOH represent a significant pathway by which organic pollutants in illuminated surface waters receiving acidic mine drainage runoff may be consumed

  5. Remediation of acid mine drainage at the friendship hill national historic site with a pulsed limestone bed process

    Sibrell, P.L.; Watten, B.; Boone, T.

    2003-01-01

    A new process utilizing pulsed fluidized limestone beds was tested for the remediation of acid mine drainage at the Friendship Hill National Historic Site, in southwestern Pennsylvania. A 230 liter-per-minute treatment system was constructed and operated over a fourteen-month period from June 2000 through September 2001. Over this period of time, 50,000 metric tons of limestone were used to treat 50 million liters of water. The influent water pH was 2.5 and acidity was 1000 mg/L as CaCO3. Despite the high potential for armoring at the site, effluent pH during normal plant operation ranged from 5.7 to 7.8 and averaged 6.8. As a result of the high influent acidity, sufficient CO2 was generated and recycled to provide a net alkaline discharge with about 50 mg/L as CaCO3 alkalinity. Additions of commercial CO2 increased effluent alkalinity to as high as 300 mg/L, and could be a useful process management tool for transient high flows or acidities. Metal removal rates were 95% for aluminum (60 mg/L in influent), 50 to 90% for iron (Fe), depending on the ratio of ferrous to ferric iron, which varied seasonally (200 mg/L in influent), and process in treatment of acid impaired waters that were previously not amenable to low cost limestone treatment.

  6. Weathering behaviour of overburden-coal ash blending in relation to overburden management for acid mine drainage prevention in coal surface mine

    Potentially acid forming (PAF) materials are encapsulated with non-acid forming materials (NAF) in order to prevent acid mine drainage (AMD) in surface coal mines. NAF compaction techniques with fly and bottom ashes from coal-fired power plants are used in mines with limited amounts of NAF materials. This study investigated the weathering behaviour of blended overburden and coal combustion ash in laboratory conditions. Free draining column leach tests were conducted on different blending schemes. The weathering process was simulated by spraying the samples with de-ionized water once per day. The leachates were then analyzed using X-ray diffraction and fluorescence analyses in order to identify the mineral composition of the samples over a 14 week period. Results of the study indicated that the weathering process plays a significant role in controlling infiltration rates, and may increase the capability of capping materials to prevent infiltration into PAF materials. Fly- and bottom-ash additions improved the performance of the encapsulation materials. 3 refs., 4 tabs., 2 figs.

  7. Behaviour of U-Series Radionuclides in an Estuary Affected by Acid Mine Drainage and Industrial Releases

    The estuary formed by the Tinto and Odiel rivers is an ecosystem of great interest because it is seriously affected by the acid mine drainage (AMD) produced by the high mining activity in the watersheds of these rivers, generating in their waters an extremely low pH (2.5- 3.5), and consequently high concentrations of heavy metals and natural radionuclides in dissolution. Secondly, in their estuary there is a large chemical industrial complex, and in particular two phosphoric acid production plants, which use a sedimentary phosphate rock from Morocco as raw material containing at approximately 1.5 Bq/g of U-series radionuclides, which produce annually about 2.5-3 millions of tonnes of a byproduct, called phosphogypsum (PG). PG contains high concentrations of some U-series radionuclides as 226Ra (650 Bq/kg), 210Pb-210Po (600 Bq/kg) or 230Th (450 Bq/kg). Seventeen sampling stations along the end of these rivers and this estuary were selected to study the behaviour of U-series radionuclides in the recent surface sediments and its waters. The most relevant results show a non-conservative behaviour of Uisotopes, precipitating in the zone where large pH changes (3-5) are produced. This behaviour is different from the majority of typical estuaries where only salinity changes are produced, and therefore, a conservative behaviour of uranium is observed. (author)

  8. Strontium isotope quantification of siderite, brine and acid mine drainage contributions to abandoned gas well discharges in the Appalachian Plateau

    Chapman, Elizabeth C. [Univ. of Pittsburgh, PA (United States). Dept. of Geology and Planetary Science; Capo, Rosemary C. [Univ. of Pittsburgh, PA (United States). Dept. of Geology and Planetary Science; Stewart, Brian W. [Univ. of Pittsburgh, PA (United States). Dept. of Geology and Planetary Science; Hedin, Robert S. [Hedin Environmental, Pittsburgh, PA (United States); Weaver, Theodore J. [Hedin Environmental, Pittsburgh, PA (United States); Edenborn, Harry M. [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States)

    2013-04-01

    Unplugged abandoned oil and gas wells in the Appalachian region can serve as conduits for the movement of waters impacted by fossil fuel extraction. Strontium isotope and geochemical analysis indicate that artesian discharges of water with high total dissolved solids (TDS) from a series of gas wells in western Pennsylvania result from the infiltration of acidic, low Fe (Fe < 10 mg/L) coal mine drainage (AMD) into shallow, siderite (iron carbonate)-cemented sandstone aquifers. The acidity from the AMD promotes dissolution of the carbonate, and metal- and sulfate-contaminated waters rise to the surface through compromised abandoned gas well casings. Strontium isotope mixing models suggest that neither upward migration of oil and gas brines from Devonian reservoirs associated with the wells nor dissolution of abundant nodular siderite present in the mine spoil through which recharge water percolates contribute significantly to the artesian gas well discharges. Natural Sr isotope composition can be a sensitive tool in the characterization of complex groundwater interactions and can be used to distinguish between inputs from deep and shallow contamination sources, as well as between groundwater and mineralogically similar but stratigraphically distinct rock units. This is of particular relevance to regions such as the Appalachian Basin, where a legacy of coal, oil and gas exploration is coupled with ongoing and future natural gas drilling into deep reservoirs.

  9. Adsorption of copper, cadmium and zinc on suspended sediments in a stream contaminated by acid mine drainage: The effect of seasonal changes in dissolved organic carbon

    The release of metal-rich, acidic waters from abandoned mining operations is a major problem in Colorado and throughout the Western United States. In Colorado, over 600 km of stream reach are estimated to be affected by such releases (Wentz, 1974). The metals released adversely affect stream biota, including fish. It is therefore important to understand the chemical processes which influence metal transport in these waters. The report details studies of the role of suspended sediments with respect to the transport of several important trace metals in a stream impacted by acid mine drainage. The role of streambed sediments was studied in the same system as part of an earlier project (Acid Mine Drainage: streambed sorption of copper, cadmium and zinc, PB--93-118263)

  10. Evaluation of the effects of water hardness and chemical pollutants on the zooplankton community in uranium mining lakes with acid mine drainage

    Nascimento, H.; Ferrari, C.; Nascimento, M.R. [Brazilian Nulcear Energy Commission/Pocos de Caldas Laboratory (Brazil); Rodgher, S. [Universidade Estadual Paulista Julio de Mesquita Filho/Science and Technology Institute (Brazil); Wisniewski, M.J. [Alfenas Federal University/Limnology Laboratory (Brazil)

    2014-07-01

    Several mining lakes are characterized by the inorganic pollution of its waters, known as acid mine drainage (AMD). The current study was developed in order to evaluate the effect of water hardness and chemical pollutants on the richness and density of the zoo-planktonic community species. A seasonal study was conducted in a uranium mining lake affected by AMD. In environmental conditions of extremely high hardness water values (960.3 to 1284,9 mg/l), zoo-planktonic species have indicated resistance to the combined effect of elevated average concentrations of chemical pollutants such as Al (81.9 mg/l), Zn (15.5 mg/l), Mn (102.8 mg/l), U (2.9 mg/l) and low pH values (average = 3.8). Thus, in environments of extreme chemical conditions, such as a uranium mining lake affected by AMD, the hardness showed to be the best predictor of the zoo-planktonic community richness, indicating a protective effect of ions Ca{sup +2} over in special to Bosminopsis deitersi, Bosmina sp., Keratella americana and K. cochlearis. Document available in abstract form only. (authors)

  11. Generation of acid mine drainage around the Karaerik copper mine (Espiye, Giresun, NE Turkey): implications from the bacterial population in the Acısu effluent.

    Sağlam, Emine Selva; Akçay, Miğraç; Çolak, Dilşat Nigar; İnan Bektaş, Kadriye; Beldüz, Ali Osman

    2016-09-01

    The Karaerik Cu mine is a worked-out deposit with large volumes of tailings and slags which were left around the mine site without any protection. Natural feeding of these material and run-off water from the mineralised zones into the Acısu effluent causes a serious environmental degradation and creation of acid mine drainage (AMD) along its entire length. This research aims at modelling the formation of AMD with a specific attempt on the characterisation of the bacterial population in association with AMD and their role on its occurrence. Based on 16SrRNA analyses of the clones obtained from a composite water sample, the bacterial community was determined to consist of Acidithiobacillus ferrivorans, Ferrovum myxofaciens, Leptospirillum ferrooxidans and Acidithiobacillus ferrooxidans as iron-oxidising bacteria, Acidocella facilis, Acidocella aluminiidurans, Acidiphilium cryptum and Acidiphilium multivorum as iron-reducing bacteria, and Acidithiobacillus ferrivorans, Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Acidiphilium cryptum as sulphur-oxidising bacteria. This association of bacteria with varying roles was interpreted as evidence of a concomitant occurrence of sulphur and iron cycles during the generation of AMD along the Acısu effluent draining the Karaerik mine. PMID:27338270

  12. Evaluation of the effects of water hardness and chemical pollutants on the zooplankton community in uranium mining lakes with acid mine drainage

    Several mining lakes are characterized by the inorganic pollution of its waters, known as acid mine drainage (AMD). The current study was developed in order to evaluate the effect of water hardness and chemical pollutants on the richness and density of the zoo-planktonic community species. A seasonal study was conducted in a uranium mining lake affected by AMD. In environmental conditions of extremely high hardness water values (960.3 to 1284,9 mg/l), zoo-planktonic species have indicated resistance to the combined effect of elevated average concentrations of chemical pollutants such as Al (81.9 mg/l), Zn (15.5 mg/l), Mn (102.8 mg/l), U (2.9 mg/l) and low pH values (average = 3.8). Thus, in environments of extreme chemical conditions, such as a uranium mining lake affected by AMD, the hardness showed to be the best predictor of the zoo-planktonic community richness, indicating a protective effect of ions Ca+2 over in special to Bosminopsis deitersi, Bosmina sp., Keratella americana and K. cochlearis. Document available in abstract form only. (authors)

  13. Immobilization of arsenite and ferric iron by Acidithiobacillus ferrooxidans and its relevance to acid mine drainage.

    Duquesne, K; Lebrun, S; Casiot, C; Bruneel, O; Personné, J-C; Leblanc, M; Elbaz-Poulichet, F; Morin, G; Bonnefoy, V

    2003-10-01

    Weathering of the As-rich pyrite-rich tailings of the abandoned mining site of Carnoulès (southeastern France) results in the formation of acid waters heavily loaded with arsenic. Dissolved arsenic present in the seepage waters precipitates within a few meters from the bottom of the tailing dam in the presence of microorganisms. An Acidithiobacillus ferrooxidans strain, referred to as CC1, was isolated from the effluents. This strain was able to remove arsenic from a defined synthetic medium only when grown on ferrous iron. This A. ferrooxidans strain did not oxidize arsenite to arsenate directly or indirectly. Strain CC1 precipitated arsenic unexpectedly as arsenite but not arsenate, with ferric iron produced by its energy metabolism. Furthermore, arsenite was almost not found adsorbed on jarosite but associated with a poorly ordered schwertmannite. Arsenate is known to efficiently precipitate with ferric iron and sulfate in the form of more or less ordered schwertmannite, depending on the sulfur-to-arsenic ratio. Our data demonstrate that the coprecipitation of arsenite with schwertmannite also appears as a potential mechanism of arsenite removal in heavily contaminated acid waters. The removal of arsenite by coprecipitation with ferric iron appears to be a common property of the A. ferrooxidans species, as such a feature was observed with one private and three collection strains, one of which was the type strain. PMID:14532077

  14. Immobilization of Arsenite and Ferric Iron by Acidithiobacillus ferrooxidans and Its Relevance to Acid Mine Drainage

    Duquesne, K.; Lebrun, S.; Casiot, C.; Bruneel, O.; Personné, J.-C.; Leblanc, M.; Elbaz-Poulichet, F.; Morin, G.; Bonnefoy, V.

    2003-01-01

    Weathering of the As-rich pyrite-rich tailings of the abandoned mining site of Carnoulès (southeastern France) results in the formation of acid waters heavily loaded with arsenic. Dissolved arsenic present in the seepage waters precipitates within a few meters from the bottom of the tailing dam in the presence of microorganisms. An Acidithiobacillus ferrooxidans strain, referred to as CC1, was isolated from the effluents. This strain was able to remove arsenic from a defined synthetic medium only when grown on ferrous iron. This A. ferrooxidans strain did not oxidize arsenite to arsenate directly or indirectly. Strain CC1 precipitated arsenic unexpectedly as arsenite but not arsenate, with ferric iron produced by its energy metabolism. Furthermore, arsenite was almost not found adsorbed on jarosite but associated with a poorly ordered schwertmannite. Arsenate is known to efficiently precipitate with ferric iron and sulfate in the form of more or less ordered schwertmannite, depending on the sulfur-to-arsenic ratio. Our data demonstrate that the coprecipitation of arsenite with schwertmannite also appears as a potential mechanism of arsenite removal in heavily contaminated acid waters. The removal of arsenite by coprecipitation with ferric iron appears to be a common property of the A. ferrooxidans species, as such a feature was observed with one private and three collection strains, one of which was the type strain. PMID:14532077

  15. Polonium behaviour in reservoirs potentially affected by acid mine drainage (AMD) in the Iberian Pyrite Belt (SW of Spain).

    Blasco, M; Gázquez, M J; Pérez-Moreno, S M; Grande, J A; Valente, T; Santisteban, M; de la Torre, M L; Bolívar, J P

    2016-02-01

    The province of Huelva is one of the areas most affected by acid mine drainage (AMD) in the world, which can produce big enhancements and fractionations in the waters affected by AMD. There are very few studies on this issue, and none on polonium-210. Twenty-two water reservoirs were sampled, and the (210)Po was measured in both dissolution and particulate phases. The (210)Po concentrations in the waters were in the same order of magnitude to those ones for unperturbed systems, although the data published to particulate matter are very scarce. A mean value and standard uncertainty for (210)Po of 0.25 ± 0.03 mBq L(-1) in the dissolved matter, and 62 ± 9 mBq g(-1) in the particulate matter can be established as base line for the reservoirs of the Huelva area. The distribution coefficients (kd) range from 10(4) to 10(6) L kg(-1), in agreement to the found ones by other authors for the case of neutral waters, but being the lowest values for the more acidic reservoirs. It has been also found that (210)Po has a high tendency to be associated to the particulate matter for neutral-alkaline waters, however, under extreme acid conditions (pH waters of reservoirs, but the acidity has a clear influence on its distribution between both dissolved and the particulate phases. PMID:26650826

  16. Isotope geochemistry of drainage from an acid mine impaired watershed, Oakland, California

    Oxidation of sulfides at the Leona Heights Sulfur Mine has resulted in the liberation of acid, SO4 and metals to Leona Creek. Previous research at the site has indicated Fe(II) oxidation at rates faster than would be predicted by abiotic oxidation alone, particularly in the segment of stream between the Adit and Leona Street sample stations. In order to assess the mechanisms responsible for sulfide oxidation, samples were collected for isotopic analysis of water and SO4, the results of which were used to develop a stoichiometric isotope-balance model. This exercise indicated that the percentage of water-derived oxygen in SO4 increased spatially from between 56% and 64% at the Adit to between 71% and 72% at Leona Street, illustrating that increased sulfide oxidation via Fe(III) was occurring within, or as water flows over, the waste rock, relative to water emanating directly from the former mine. The incorporation of water-derived oxygen in SO4 during pyrite oxidation is a process controlled by Fe oxidizing bacteria such as A. ferrooxidans at low pH. The role of bacteria was further supported by estimates of the rate constant for Fe oxidation between sampling stations, yielding values that were approximately 106 faster than abiotic Fe oxidation alone. Stable isotopic analysis of water further indicates a close correlation of adit spring water to the local meteoric water line, while 3H data indicate a groundwater apparent age, or time of travel from its primary zone of recharge, of 34S data, in conjunction with reported albitized feldspars within the Leona Rhyolite host rock, indicate a magmatic origin of ore sulfur, contrary to previous interpretations at the site

  17. The development of bio-carbon adsorbents from Lodgepole Pine to remediate acid mine drainage in the Rocky Mountains

    Activated carbon adsorbents were produced from biomass locally available in the Rocky Mountain West, e.g. Lodgepole Pine (Pinus contorta), by vacuum pyrolysis at moderate temperatures followed by steam activation, for use as metal adsorbents for acid mine drainage (AMD). Wood cubes from fresh cut Lodgepole Pine (P. contorta) with different sizes, 3 and 12 mm, were made. Sawdust was also used to study the effect of sample size as well as sample material. We applied chemical pretreatment with potassium hydroxide before charring to improve the quality of the activated carbons. We compared the characteristics of the activated carbons, which were chemically pretreated, before and after washing with water. After washing, the BET surface area was found to increase and diffuse reflectance infrared spectroscopy showed changes in the carbon matrix. We then tested the samples for metal adsorption from AMD sampled from AMD sites in Colorado, Clear Creek County and the Leadville mine drainage tunnel, along with a commercial activated carbon for comparison. We used a batch method to measure maximum metal adsorption of the activated carbons. The metals chosen to be monitored were copper, cadmium, manganese, nickel, lead, and zinc, because they are the principal metals of interest for the test areas, and metal concentrations were determined by ion coupled plasma-atomic emission spectroscopy. The samples produced in this work outperformed the commercial activated carbon in two AMD water treatment tests and for the six metals monitored. This metal adsorption data indicate that locally produced inexpensive activated carbons can be used as adsorbents for AMD successfully

  18. Environmental assessment and management of metal-rich wastes generated in acid mine drainage passive remediation systems.

    Macías, Francisco; Caraballo, Manuel A; Nieto, José Miguel

    2012-08-30

    As acid mine drainage (AMD) remediation is increasingly faced by governments and mining industries worldwide, the generation of metal-rich solid residues from the treatments plants is concomitantly raising. A proper environmental management of these metal-rich wastes requires a detailed characterization of the metal mobility as well as an assessment of this new residues stability. The European standard leaching test EN 12457-2, the US EPA TCLP test and the BCR sequential extraction procedure were selected to address the environmental assessment of dispersed alkaline substrate (DAS) residues generated in AMD passive treatment systems. Significant discrepancies were observed in the hazardousness classification of the residues according to the TCLP or EN 12457-2 test. Furthermore, the absence of some important metals (like Fe or Al) in the regulatory limits employed in both leaching tests severely restricts their applicability for metal-rich wastes. The results obtained in the BCR sequential extraction suggest an important influence of the landfill environmental conditions on the metals released from the wastes. To ensure a complete stability of the pollutants in the studied DAS-wastes the contact with water or any other leaching solutions must be avoided and a dry environment needs to be provided in the landfill disposal selected. PMID:22717063

  19. Relationships between sources of acid mine drainage and the hydrochemistry of acid effluents during rainy season in the Iberian Pyrite Belt.

    Pérez-Ostalé, E; Grande, J A; Valente, T; de la Torre, M L; Santisteban, M; Fernández, P; Diaz-Curiel, J

    2016-01-01

    In the Iberian Pyrite Belt (IPB), southwest Spain, a prolonged and intense mining activity of more than 4,500 years has resulted in almost a hundred mines scattered through the region. After years of inactivity, these mines are still causing high levels of hydrochemical degradation in the fluvial network. This situation represents a unique scenario in the world, taking into consideration its magnitude and intensity of the contamination processes. In order to obtain a benchmark regarding the degree of acid mine drainage (AMD) pollution in the aquatic environment, the relationship between the areas occupied by the sulfide mines and the characteristics of the respective effluents after rainfall was analysed. The methodology developed, which includes the design of a sampling network, analytical treatment and cluster analysis, is a useful tool for diagnosing the contamination level by AMD in an entire metallogenic province, at the scale of each mining group. The results presented the relationship between sulfate, total dissolved solids and electrical conductivity, as well as other parameters that are typically associated with AMD and the major elements that compose the polymetallic sulfides of IPB. This analysis also indicates the low level of proximity between the affectation area and the other variables. PMID:26819390

  20. Enrichment of rare earth elements as environmental tracers of contamination by acid mine drainage in salt marshes: a new perspective.

    Delgado, Joaquín; Pérez-López, Rafael; Galván, Laura; Nieto, José Miguel; Boski, Tomasz

    2012-09-01

    Rare earth elements (REE) were analyzed in surface sediments from the Guadiana Estuary (SW Iberian Pyrite Belt). NASC (North American Shale Composite) normalized REE patterns show clearly convex curvatures in middle-REE (MREE) with respect to light- and heavy-REE, indicating acid-mixing processes between fluvial waters affected by acid mine drainage (AMD) and seawater. However, REE distributions in the mouth (closer to the coastal area) show slightly LREE-enriched and flat patterns, indicating saline-mixing processes typical of the coastal zone. NASC-normalized ratios (La/Gd and La/Yb) do not discriminate between both mixing processes in the estuary. Instead, a new parameter (E(MREE)) has been applied to measure the curvature in the MREE segment. The values of E(MREE)>0 are indicative of acid signatures and their spatial distribution reveal the existence of two decantation zones from flocculation processes related to drought periods and flood events. Studying REE fractionation through the E(MREE) may serve as a good proxy for AMD-pollution in estuarine environments in relation to the traditional methods. PMID:22748838

  1. Inhibition of acid mine drainage and immobilization of heavy metals from copper flotation tailings using a marble cutting waste

    Gulsen Tozsin

    2016-01-01

    Acid mine drainage (AMD) with high concentrations of sulfates and metals is generated by the oxidation of sulfide bearing wastes. CaCO3-rich marble cutting waste is a residual material produced by the cutting and polishing of marble stone. In this study, the feasibility of using the marble cutting waste as an acid-neutralizing agent to inhibit AMD and immobilize heavy metals from copper flotation tailings (sul-fide-bearing wastes) was investigated. Continuous-stirring shake-flask tests were conducted for 40 d, and the pH value, sulfate content, and dissolved metal content of the leachate were analyzed every 10 d to determine the effectiveness of the marble cutting waste as an acid neu-tralizer. For comparison, CaCO3 was also used as a neutralizing agent. The average pH value of the leachate was 2.1 at the beginning of the experiment (t = 0). In the experiment employing the marble cutting waste, the pH value of the leachate changed from 6.5 to 7.8, and the sul-fate and iron concentrations decreased from 4558 to 838 mg/L and from 536 to 0.01 mg/L, respectively, after 40 d. The marble cutting waste also removed more than 80wt% of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) from AMD generated by copper flotation tailings.

  2. Enrichment of rare earth elements as environmental tracers of contamination by acid mine drainage in salt marshes: A new perspective

    Rare earth elements (REE) were analyzed in surface sediments from the Guadiana Estuary (SW Iberian Pyrite Belt). NASC (North American Shale Composite) normalized REE patterns show clearly convex curvatures in middle-REE (MREE) with respect to light- and heavy-REE, indicating acid-mixing processes between fluvial waters affected by acid mine drainage (AMD) and seawater. However, REE distributions in the mouth (closer to the coastal area) show slightly LREE-enriched and flat patterns, indicating saline-mixing processes typical of the coastal zone. NASC-normalized ratios (La/Gd and La/Yb) do not discriminate between both mixing processes in the estuary. Instead, a new parameter (EMREE) has been applied to measure the curvature in the MREE segment. The values of EMREE > 0 are indicative of acid signatures and their spatial distribution reveal the existence of two decantation zones from flocculation processes related to drought periods and flood events. Studying REE fractionation through the EMREE may serve as a good proxy for AMD-pollution in estuarine environments in relation to the traditional methods.

  3. Inhibition of acid mine drainage and immobilization of heavy metals from copper flotation tailings using a marble cutting waste

    Tozsin, Gulsen

    2016-01-01

    Acid mine drainage (AMD) with high concentrations of sulfates and metals is generated by the oxidation of sulfide bearing wastes. CaCO3-rich marble cutting waste is a residual material produced by the cutting and polishing of marble stone. In this study, the feasibility of using the marble cutting waste as an acid-neutralizing agent to inhibit AMD and immobilize heavy metals from copper flotation tailings (sulfide- bearing wastes) was investigated. Continuous-stirring shake-flask tests were conducted for 40 d, and the pH value, sulfate content, and dissolved metal content of the leachate were analyzed every 10 d to determine the effectiveness of the marble cutting waste as an acid neutralizer. For comparison, CaCO3 was also used as a neutralizing agent. The average pH value of the leachate was 2.1 at the beginning of the experiment ( t = 0). In the experiment employing the marble cutting waste, the pH value of the leachate changed from 6.5 to 7.8, and the sulfate and iron concentrations decreased from 4558 to 838 mg/L and from 536 to 0.01 mg/L, respectively, after 40 d. The marble cutting waste also removed more than 80wt% of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) from AMD generated by copper flotation tailings.

  4. Predicting the occurrence of acid mine drainage in the Alleghenian coal-bearing strata of western Pennsylvania

    This paper reports that simulated weathering experiments on coals and shales demonstrate that the critical factors responsible for the generation of acid mine drainage (AMD) are the amounts of total sulfur, total carbonate, and the surface area of the pyrite. Total sulfur and carbonate carbon contents differ markedly among paleoenvironments whose distribution has been mapped for the Alleghenian state of western Pennsylvania. Freshwater (Estheria-bearing) shales have a mean total sulfur content of 0.15 percent and a mean carbonate carbon content of 0.54 percent. Brackish (Lingula-bearing) shales have a mean total sulfur content of 2.40 percent and a mean carbonate carbon content of 0.14 percent. Marine (Chonetes-bearing) shales have a mean total sulfur content of 0.95 percent and a mean carbonate carbon content of 0.63 percent. In the simulated weathering experiments, the amount of acidity, sulfate, and total iron exhibit a well-defined positive linear relation with total sulfur in samples whose carbonate carbon content is ≤ 0.01 percent. Where carbonate carbon contents are >0.01 percent, the amount of acidity, sulfate, and total iron is considerably less, and the linear relation no longer exists

  5. Current Performance of an Aerobic Passive Wetlands Treating Acid Mine Drainage Flow From Underground Mine Seals at Moraine State Park, Butler County, Pennsylvania

    Winter, J. A.; Fredrick, K.

    2008-12-01

    Coal mining was conducted in the area of Moraine State Park prior to the establishing the park and associated Lake Arthur. A total of 69 underground mine entries were sealed during the 1960's to the early 1970's along the proposed northern shore of Lake Arthur. Seals were constructed using a flyash/cement mixture that was pumped into boreholes to place bulkheads in the mine entries, then filling between the bulkheads, and injecting grout into the adjacent strata to form a grout curtain. During 1979 and 1980, a study was performed by the United States Department of the Interior, Bureau of Mines, to determine the long term effectiveness of the underground mine sealing and reclamation work. Not all seals were successful. One of these mine entry seals was leaking and depositing iron hydroxides on the shoreline. During 1995-96, a passive wetlands treatment system was designed and constructed to treat an acid mine drainage (amd) discharge emanating from one of these sealed mines. The system consists of a primary settling pond, a cattail vegetated pond, and a final polishing pond prior to discharge to Lake Arthur. The design life of the system was estimated at twelve years. After twelve years it was believed the precipitate in the ponds would need to be removed and the system rehabilitated to continue treating the amd discharge. A maintenance plan was considered, however only minimal maintaining of the area was implemented. Six sets of water quality samples were collected and analyzed for standard amd parameters of alkalinity, acidity, pH, iron, manganese, aluminum, sulfate, and total suspended solids. Precipitation data and flow rates were collected and an analysis was done to determine if flow varied seasonally. The water quality data was compared to flow and precipitation amounts. Sludge precipitate samples were collected from the first settling pond to estimate the deposition rate and to determine how long the ponds can continue to function before they would require

  6. Reconnaissance of Acid Drainage Sources and Preliminary Evaluation of Remedial Alternatives at the Copper Bluff Mine, Hoopa Valley Reservation, California

    Alpers, Charles N.; Hunerlach, Michael P.; Hamlin, Scott N.; Zierenberg, Robert A.

    2003-01-01

    Acidic drainage from the inactive Copper Bluff mine cascades down a steep embankment into the Trinity River, on the Hoopa Valley Reservation in northern California. The Copper Bluff mine produced about 100,000 tons of sulfide-bearing copper-zinc-gold-silver ore during 1957?1962. This report summarizes the results of a water-resources investigation begun by the U.S. Geological Survey in 1994 with the overall objective of gathering sufficient geochemical, hydrologic, and geologic information so that a sound remediation strategy for the Copper Bluff mine could be selected and implemented by the Hoopa Valley Tribe. This study had the following specific objectives: (1) monitor the quality and quantity of the mine discharge, (2) determine seasonal variability of metal concentrations and loads, (3) map and sample the underground mine workings to determine sources of flow and suitability of mine plugging options, and (4) analyze the likely consequences of various remediation and treatment options. Analysis of weekly water samples of adit discharge over parts of two wet seasons (January to July 1995 and October 1995 to May 1996) shows that dissolved copper (Cu) and zinc (Zn) concentrations (in samples filtered with 0.20-micrometer membranes) varied systematically in a seasonal pattern. Metal concentrations increased dramatically in response to the first increase in discharge, or first flush, early in the wet season. The value of Zn/Cu in the adit discharge exhibited systematic seasonal variations; an annual Zn/Cu cycle was observed, beginning with values between 3 and 5 during the main part of the wet season, rising to values between 6 and 10 during the period of lowest discharge late in the dry season, and then dropping dramatically to values less than 3 during the first-flush period. Values of pH were fairly constant in the range of 3.1 to 3.8 throughout the wet season and into the beginning of the dry season, but rose to values between 4.5 and 5.6 during the period of

  7. Combined effects of spatially variable flow and mineralogy on the attenuation of acid mine drainage in groundwater

    Quantifications of the spreading of acid mine drainage (AMD) in groundwater are needed for risk assessments of mining sites. However, due to subsurface heterogeneity, available field data may prove insufficient for deterministic process descriptions, even at well-characterized sites. Here, the probabilistic LaSAR-PHREEQC model is used to consider multicomponent reactions and transport in heterogeneous (flow and geochemistry) groundwater surrounding a mine waste site, with specific focus on the spreading of Zn. Model results, using field data from a mill tailings impoundment in northern Sweden (including major component geochemistry), indicate that precipitation of smithsonite (ZnCO3) may drastically delay the downstream arrival of Zn, but may also cause a peak concentration once the retained Zn is released. The amount of smithsonite formed is, however, minute and its spatial variation large, such that detection of smithsonite in soil samples may be difficult. Results further show that even a low degree of flow heterogeneity can effectively smooth otherwise distinctive temporal concentration changes attributed to the considered chemical reactions, and thereby mask the attenuation processes. By contrast, the existence of preferential flow paths can cause temporally separated concentration peaks in response to a single chemical reaction chain, even in a geochemically homogeneous domain, making the interpretation of the concentration curves non-trivial. The stochastic modelling results for Zn considering flow and/or mineralogical heterogeneity indicate a less efficient Zn attenuation than predicted by standard, deterministic reactive-transport models. In addition, in all considered probabilistic Zn and SO42- scenarios, the spatial variability in downstream pollutant concentration was high, implying that a relatively large number of point samples are needed to determine field-scale mean concentrations

  8. Acid mine drainage abatement from small, buried piles of tipple refuse using fluidized bed fly ash grout

    Buried, pyrite-rich tipple refuse and pit cleanings on a reclaimed 37 acre surface coal mine site in Pennsylvania were found to be producing severe acid mine drainage (AMD). The pyritic material is located in discrete piles or pods in the backfill. The pods and the resulting contaminant plumes were initially defined using geophysical techniques and were confirmed by drilling. A fluidized bed combustion (FBC) fly ash was used as a grout in two different ways to isolate the pyritic material from water and oxygen, thus preventing AMD production. The first was pressure injecting grout directly into the buried pods to fill the void spaces within the pods and to coat the pyritic materials with a cementitious layer. Pods which would not accept the grout because of a clayey matrix were isolated from percolating water with a cap and trench seal of the grout. In certain areas, the AMD migrates to the groundwater table below the mine through fractures in the pit floor. The FBC ash grout was used in some of these areas in an attempt to seal the pit floor. A combination of geophysical mapping and monitoring wells is being used to monitor changes in the water quality. Minimal surface disturbance is required because only the sources of severe AMD production were targeted with the grout applications. Reduced costs are also possible since the FBC ash is a waste product. This methodology is designed as a true abatement technique requiring no future maintenance. The project was nearing completion at the time of this writing. This paper is an interim report

  9. An evaluation of problems arising from acid mine drainage in the vicinity of Shasta Lake, Shasta County, California

    Fuller, Richard H.; Shay, J.M.; Ferreira, R.F.; Hoffman, R.J.

    1978-01-01

    Streams draining the mined areas of massive sulfide ore deposits in the Shasta Mining Districts of northern California are generally acidic and contain large concentrations of dissolved metals, including iron, copper, and zinc. The streams, including Flat, Little Backbone, Spring, West Squaw, Horse, and Zinc Creeks, discharge into Shasta Reservoir and the Sacramento River and have caused numerous fish kills. The sources of pollution are discharge from underground mines, streams that flow into open pits, and streams that flow through pyritic mine dumps where the oxidation of pyrite and other sulfide minerals results in the production of acid and the mobilization of metals. Suggested methods of treatment include the use of air and hydraulic seals in the mines, lime neutralization of mine effluent, channeling of runoff and mine effluent away from mine and tailing areas, and the grading and sealing of mine dumps. A comprehensive preabatement and postabatement program is recommended to evaluate the effects of any treatment method used. (Woodard-USGS)

  10. Evaluation of genetic toxicity caused by acid mine drainage of coal mines on fish fauna of Simsang River, Garohills, Meghalaya, India.

    Talukdar, B; Kalita, H K; Baishya, R A; Basumatary, S; Sarma, D

    2016-09-01

    Fishery ecology of the Simsang River, Meghalaya is being threatened by large scale environmental degradation due to acid mine drainage (AMD) of coal mines. In the present paper, effort has been made to evaluate the genotoxicity caused due to AMD of coal mines on Channa punctata under laboratory condition through comet assay, micronucleus and chromosome aberration tests. Water samples were collected seasonally from affected and unaffected sites of the River and physico-chemical quality of water indicated low pH (4.6), high concentration of sulphates (270mgL(-1)) and iron (7.2mgL(-1)) beyond permissible limits. Polycyclic aromatic hydrocarbon (PAH) showed highest concentration of 4-ring PAH and Benzo[a]anthracene was the most important pollutant in the water collected from affected sites. The highest and the lowest mean concentrations of PAHs were estimated in monsoon and winter season, respectively. The index of DNA damage assessed by comet assay, micronucleus and chromosome aberration tests demonstrated significant differences season wise in different sampling sites. Frequency of DNA-damaged cells was found highest in the water samples collected from affected site in monsoon season. PMID:27213561

  11. Neutralization of acid mine drainage using the final product from CO2 emissions capture with alkaline paper mill waste

    In this study, experiments were conducted to investigate the applicability of low-cost alkaline paper mill wastes as acidity neutralizing agents for treatment of acid mine drainage (AMD). Paper wastes include a calcium mud by-product from kraft pulping, and a calcite powder from a previous study focused on sequestering CO2 by carbonation of calcium mud. The neutralization process consisted of increase of pH by alkaline additive dissolution, decrease of metals solubility and precipitation of gypsum and poorly crystallized Fe-Al oxy-hydroxides/oxy-hydroxysulphates, which acted as a sink for trace elements to that extent that solutions reached the pre-potability requirements of water for human consumption. This improvement was supported by geochemical modelling of solutions using PHREEQC software, and observations by scanning electron microscope and X-ray diffraction of reaction products. According to PHREEQC simulations, the annual amount of alkaline additive is able to treat AMD (pH 3.63, sulphate 3800 mg L-1, iron 348 mg L-1) with an average discharge of about 114 and 40 L s-1 for calcium mud and calcite powder, respectively. Likewise, given the high potential of calcium mud to sequester CO2 and of resulting calcite powder to neutralize AMD, paper wastes could be a promising solution for facing this double environmental problem.

  12. Geochemical Niches of Iron-Oxidizing Acidophiles in Acidic Coal Mine Drainage

    Jones, Daniel S.; Kohl, Courtney; Grettenberger, Christen; Larson, Lance N.; Burgos, William D.; Macalady, Jennifer L.

    2014-01-01

    A legacy of coal mining in the Appalachians has provided a unique opportunity to study the ecological niches of iron-oxidizing microorganisms. Mine-impacted, anoxic groundwater with high dissolved-metal concentrations emerges at springs and seeps associated with iron oxide mounds and deposits. These deposits are colonized by iron-oxidizing microorganisms that in some cases efficiently remove most of the dissolved iron at low pH, making subsequent treatment of the polluted stream water less ex...

  13. Diminished Metal Accumulation in Riverine Fishes Exposed to Acid Mine Drainage over Five Decades

    Ross A Jeffree; Markich, Scott J.; Twining, John R.

    2014-01-01

    Bony bream (Nematalosa erebi) and black catfish (Neosilurus ater) were sampled from the fresh surface waters of the Finniss River in tropical northern Australia, along a metal pollution gradient draining the Rum Jungle copper/uranium mine, a contaminant source for over five decades. Paradoxically, populations of both fish species exposed to the highest concentrations of mine-related metals (cobalt, copper, lead, manganese, nickel, uranium and zinc) in surface water and sediment had the lowest...

  14. Hydrogeology and geochemistry of acid mine drainage in ground water in the vicinity of Penn Mine and Camanche Reservoir, Calaveras County, California; first-year summary

    Hamlin, S.N.; Alpers, C.N.

    1995-01-01

    Acid drainage from the Penn Mine in Calaveras County, California, has caused contamination of ground water between Mine Run Dam and Camanche Reservoir. The Penn Mine was first developed in the 1860's primarily for copper and later produced lesser amounts of zinc, lead, silver, and gold from steeply dipping massive sulfide lenses in metamorphic rocks. Surface disposal of sulfidic waste rock and tailings from mine operations has produced acidic drainage with pH values between 2.3 and 2.7 and elevated concentrations of sulfate and metals, including copper, zinc, cadmium, iron, and aluminum. During the mine's operation and after its subsequent abandonment in the late 1950's, acid mine drainage flowed down Mine Run into the Mokelumne River. Construction of Camanche Dam in 1963 flooded part of the Mokelumne River adjacent to Penn Mine. Surface-water diversions and unlined impoundments were constructed at Penn Mine in 1979 to reduce runoff from the mine, collect contaminated surface water, and enhance evaporation. Some of the contaminated surface water infiltrates the ground water and flows toward Camanche Reservoir. Ground- water flow in the study area is controlled by the local hydraulic gradient and the hydraulic characteristics of two principal rock types, a Jurassic metavolcanic unit and the underlying Salt Spring slate. The hydraulic gradient is west from Mine Run impoundment toward Camanche Reservoir. The median hydraulic conductivity was about 10 to 50 times higher in the metavolcanic rock (0.1 foot per day) than in the slate (0.002 to 0.01 foot per day); most flow occurs in the metavolcanic rock where hydraulic conductivity is as high as 50 feet per day in two locations. The contact between the two rock units is a fault plane that strikes N20?W, dips 20?NE, and is a likely conduit for ground-water flow, based on down-hole measurements with a heatpulse flowmeter. Analyses of water samples collected during April 1992 provide a comprehensive characterization of

  15. Acid drainages of the pyritic sterile from the Pocos de Caldas uranium mine: environmental interpretation and implications

    Considering the planned closure of the first uranium mine and milling plant operating in Brazil, located in the Pocos de Caldas Plateau, in the State of Minas Gerais, in the next two years, there is the need to obtain basic information for its decommissioning. Special attention has been directed to the following critical areas: open pit, tailing, dam and waste rock piles, because these are the main sources of acid drainage generation. These waters cannot be allowed to flow in the external environment because in addition to sulphuric acid, there is a number of elements in concentration above those allowed by regulations. Among the waste piles (bota-foras BF) two of them BF-4 and BF-8, are in a process of acid generation, thus requiring more attention. The objective of this work was to simulate at the laboratory scale the oxidation and the reduction zones of BF-4. The experiments were conducted in acrylic columns, where the waste sample was kept under aerated and saturated conditions, in different columns. The control of the chemical (solubilized chemical species), physico-chemical (redox potential, pH, conductivity) and biological (bacterial activity) parameters has been carried out on the acid solutions generated by the chemical and biological reactions that occur at the waste. Although the results refer to a four month period, some relevant points can be highlighted, which will serve as a basis for further research. The mineralogical characterization identified the existence of other sulphides associated to pyrite with lower oxidation potential than the latter. The results obtained with the biological characterization for the two conditions studied revealed that the bacterial activity is more intense in the region in contact with air, than in saturated region. (author)

  16. Temporal and spatial variability of acid rock drainage in a rehabilitated coal mine, Wangaloa, South Otago, New Zealand

    The Wangaloa open cast coal mine ceased operations in 1989, with no restoration of the 252 ha site, and moderate acid rock drainage developed. A major rehabilitation programme was initiated in 2002 with removal of exotic vegetation, and extensive planting (>60,000) of native seedlings was begun in 2003. By 2006, most seedlings were thriving, and, combined with adventive exotic weeds, a 70% vegetation cover had been achieved. The site substrates were highly variable on the 10-100 m2 scale, and have been characterised by paste pH (>700 measurements). In 2003, substrates had moderate acidity (pH 4.5 ± 0.9) with distinctly acid patches (pH down to 100 samples from 15 sites) were also highly variable spatially and temporally. Incoming stream and rainwater (pH 5-6) chemically interacted with acid substrates, especially waste rock piles that contain pyrite-bearing material, and evolved to lower pH (pH down to 3.4), sulfate-rich waters. A pit lake on the site receives most surface and groundwater runoff, and this lake, with a water residence time of 1-2 yr, controls the site discharge water quality. The lake pH varies on a monthly time-scale from 4.5 to 6.5, synchronised with pH variations in groundwater boreholes in waste rock. In addition, there has been a general increase in pH of the lake during rehabilitation from consistent pH 4.6-4.8 before rehabilitation to near pH 6 during rehabilitation. The sulfate/chloride ratio of lake water has decreased from 20 to <10 during rehabilitation as well. These changes in lake water composition from year to year may be a result of increased input of rainwater that has had less interaction with substrate than runoff water had before rehabilitation began. (author). 23 refs., 10 figs., 1 tab

  17. Inorganic contaminants attenuation in acid mine drainage by fly ash and fly ash-ordinary Portland cement (OPC) blends : column experiments

    The infiltration of acid mine drainage (AMD) material into mine voids is one of the environmental impacts of underground coal mining. In this study, the mitigation of AMD in a mine void was simulated in laboratory conditions. Various mixtures of fly ash, solid residues, and Portland cement were added to packed columns over a 6-month period. The fly ash additions generated near-neutral to alkaline pH levels, which in turn induced precipitation, co-precipitation, and adsorption contaminant attenuation mechanisms. A modelling study demonstrated that the precipitation of ferrihydrite, Al-hydroxides, Al-oxyhydroxysulphates, gypsum, ettringite, manganite, and rhodochrosite lowered contaminant levels. Results of the study indicated that the pH regime and acidity level of the AMD strongly influenced both the leaching of the toxic trace elements as well as the attenuation of the AMD. 3 refs., 2 figs.

  18. Microbial populations identified by fluorescence in situ hybridization in a constructed wetland treating acid coal mine drainage.

    Nicomrat, Duongruitai; Dick, Warren A; Tuovinen, Olli H

    2006-01-01

    Microorganisms are an integral part of the biogeochemical processes in wetlands, yet microbial communities in sediments within constructed wetlands receiving acid mine drainage (AMD) are only poorly understood. The purpose of this study was to characterize the microbial diversity and abundance in a wetland receiving AMD using fluorescence in situ hybridization (FISH) analysis. Seasonal samples of oxic surface sediments, comprised of Fe(III) precipitates, were collected from two treatment cells of the constructed wetland system. The pH of the bulk samples ranged between pH 2.1 and 3.9. Viable counts of acidophilic Fe and S oxidizers and heterotrophs were determined with a most probable number (MPN) method. The MPN counts were only a fraction of the corresponding FISH counts. The sediment samples contained microorganisms in the Bacteria (including the subgroups of acidophilic Fe- and S-oxidizing bacteria and Acidiphilium spp.) and Eukarya domains. Archaea were present in the sediment surface samples at detection in the bacterial community. The results from the FISH technique from this field study are consistent with results from other experiments involving enumeration by most probable number, dot-blot hybridization, and denaturing gradient gel electrophoresis analyses and with the geochemistry of the site. PMID:16825452

  19. Ecological benefits of passive wetland treatment systems designed for acid mine drainage: With emphasis on watershed restoration

    Western Pennsylvania has been a large source of coal for much of the US since the late 1800's. During the extraction of the coal resources, acid mine drainage (AMD) often resulted. AMD from abandoned discharges has effectively rendered thousands of kilometers of streams lifeless in the Appalachian coal region. Restoration of these streams has been limited in previous years primarily because of the lack of cost-effective treatment for AMD. Conventional treatment can treat AMD effectively but is costly to operate and maintain and is effective only when receiving human attention. Passive wetland treatment systems have proven to be the only realistic AMD treatment strategy, in terms of watershed restoration activities. If ecosystem health is the reason for implementing effluent standards then it can be reasonably argued that passive wetland treatment systems supply the most effective overall treatment, even if they do not meet one or more of the current effluent standards. Recent advancements in passive wetland treatment system technology have provided a management tool that could be used to treat the majority of AMD discharges cost-effectively, and when used strategically could reasonably be employed to restore the thousands of kilometers of AMD-affected streams in the coal regions of Appalachia. Secondary benefits that have been observed with passive wetland treatment systems suggest that these systems may be providing for accelerated ecological recovery independent of regulated effluent standards

  20. Bioaccumulation of metals in reeds collected from an acid mine drainage contaminated site in winter and spring.

    Guo, Lin; Cutright, Teresa J

    2016-07-01

    Wetland plants such as Phragmites australis has been used to treat acid mine drainage (AMD) contaminated soil which is a serious environmental issue worldwide. This project investigated metal plaque content(s) and metal uptake in reeds grown in an AMD field in winter and spring. The results indicated that the level of Fe plaque was much higher than Mn and Al plaque as the soil contained more Fe than Al and Mn. The amounts of Mn and Al plaque formed on reeds in spring were not significantly different from that in winter (p > .05). However, more Fe plaque was formed on reeds collected in spring. The concentrations of metals in underground organs were positively related to the metal levels in soils. More Mn and Al transferred to the aboveground tissues of reeds during the spring while the Fe levels in reeds did not significantly vary with seasons. Roots and rhizomes were the main organs for Fe sequestration (16.3 ± 4.15 mg/g in roots in spring) while most Al was sequestered in the shoots of reeds (2.05 ± 0.09 mg/g in shoots in spring). Further research may be needed to enhance the translocation of metals in reeds and increase the phytoremediation efficiency. PMID:26789500

  1. Water quality changes in acid mine drainage streams in Gangneung, Korea, 10 years after treatment with limestone

    Shim, Moo Joon; Choi, Byoung Young; Lee, Giehyeon; Hwang, Yun Ho; Yang, Jung-Seok; O' Loughlin, Edward J.; Kwon, Man Jae

    2015-12-01

    To determine the long-term effectiveness of the limestone treatment for acid mine drainage (AMD) in Gangneung, Korea, we investigated the elemental distribution in streams impacted by AMD and compared the results of previous studies before and approximately 10 years after the addition of limestone. Addition of limestone in 1999 leads to a pH increase in 2008, and with the exception of Ca, the elemental concentrations (e.g., Fe, Mn, Mg, Sr, Ni, Zn, S) in the streams decreased. The pH was 2.5–3 before the addition of limestone and remained stable at around 4.5–5 from 2008 to 2011, suggesting the reactivity of the added limestone was diminished and that an alternative approach is needed to increase the pH up to circumneutral range and maintain effective long-term treatment. To identify the processes causing the decrease in the elemental concentrations, we also examined the spatial (approximately 7 km) distribution over three different types of streams affected by the AMD. The elemental distribution was mainly controlled by physicochemical processes including redox reactions, dilution on mixing, and co-precipitation/adsorption with Fe (hydr)oxides.

  2. Aluminium and iron burdens of aquatic biota in New Zealand streams contaminated by acid mine drainage. Effects of trophic level

    Winterbourn, M.J. [Department of Zoology, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); McDiffett, W.F.; Eppley, S.J. [Biology Department, Bucknell University, Lewisburg, PA (United States)

    2000-05-24

    Concentrations of Al and Fe were determined in samples of filamentous algae, bryophytes and invertebrates from 24 stream sites in North Westland, South Island, New Zealand. Sites were variably contaminated by acid coal mine drainage and ranged in pH from 2.6 to 6.2. Conductivity of stream water ranged from 16 to 944 {mu}S{sub 25} cm{sup -1} and maximum concentrations of total dissolved Al and total Fe measured in two successive years were 35.5 and 32.6 mg l{sup -1}, respectively. Metal burdens of algae and bryophytes were not correlated with pH, conductivity or the concentrations of Al and Fe observed in stream water. Metal concentrations in invertebrates were significantly lower than those in plants (mg per g dry wt.), and were similar in herbivore-detritivores (mainly mayfly larvae) and carnivorous species. No evidence was found for the biomagnification of either metal within aquatic food webs. However, invertebrate species exposed to very high concentrations of Al and Fe varied considerably in body burdens, suggesting that groups of insects differ considerably in their physiological or morphological ability to exclude potentially toxic metals.

  3. Kinetics and microbial ecology of batch sulfidogenic bioreactors for co-treatment of municipal wastewater and acid mine drainage.

    Deng, Dongyang; Weidhaas, Jennifer L; Lin, Lian-Shin

    2016-03-15

    The kinetics and microbial ecology in sulfidogenic bioreactors used in a novel two-stage process for co-treatment of acid mine drainage (AMD) and municipal wastewater (MWW) were investigated. Michaelis-Menten modeling of COD oxidation by sulfate reducing bacteria (SRB) (Vmax=0.33mgL(-1)min(-1), Km=4.3mgL(-1)) suggested that the Vmax can be reasonably achieved given the typical COD values in MWW and anticipated mixing with AMD. Non-competitive inhibition modeling (Ki=6.55mgL(-1)) indicated that excessive iron level should be avoided to limit its effects on SRB. The COD oxidation rate was positively correlated to COD/sulfate ratio and SRB population, as evidenced by dsrA gene copies. Phylogenetic analysis revealed diverse microbial communities dominated by sulfate reducing delta-proteobacteria. Microbial community and relative quantities of SRB showed significant differences under different COD/sulfate ratios (0.2, 1 and 2), and the highest dsrA gene concentration and most complex microbial diversity were observed under COD/sulfate ratio 2. Major species were associated with Desulfovirga, Desulfobulbus, Desulfovibrio, and Syntrophus sp. The reported COD kinetics, SRB abundances and the phylogenetic profile provide insights into the co-treatment process and help identify the parameters of concerns for such technology development. PMID:26686479

  4. Biological fixation of metals in mine drainage and ore wastes

    Christensen, B.

    1992-01-01

    Acidic and metal-polluted drainage water from abandoned pyrite mines affect aquatic life in several resipient watercourses in Norway. A possible role of sulfate-reducing bacteria (SRB) in treatment of acidic mine water is discussed on the basis of literature studies and own experiments. SRB can generate alkalinity, remove sulfate and precipitate mental cations effectively when given appropriate growth conditions. Pure cultures og SRB were isolated from serveral mining sites and characterized ...

  5. Influence of water chemistry on the distribution of an acidophilic protozoan in an acid mine drainage system at the abandoned Green Valley coal mine, Indiana, USA

    Brake, S.S.; Dannelly, H.K.; Connors, K.A.; Hasiotis, S.T. [Indiana State University, Terre Haute, IN (United States). Dept. of Geography Geology & Anthropology

    2001-07-01

    Euglena mutabilis, a benthic photosynthetic protozoan that intracellularly sequesters Fe, is variably abundant in the main effluent channel that contains acid mine drainage (AMD) discharging from the Green Valley coal mine site in western Indiana. Samples of effluent (pH 3.0-4.6) taken from the main channel and samples of contaminated stream water (pH 3.3 to 8.0) collected from an adjacent stream were analyzed to evaluate the influence of water chemistry on E. mutabilis distribution. E. mutabilis communities were restricted to areas containing unmixed effluent with the thickest (up to 3 mm) benthic communities residing in effluent containing high concentrations of total Fe (up to 12110 mg/l), SO{sub 4}(up to 2940 mg/l), Al (up to 1846 mg/l), and Cl (up to 629 mg/l). Communities were also present, but much less abundant, in areas with effluent containing lower concentrations of these same constituents. In effluent where SO{sub 4} was most highly concentrated, E. mutabilis was largely absent, suggesting that extremely high concentrations of SO{sub 4} may have an adverse effect on this potentially beneficial Fe-mediating, acidophilic protozoan.

  6. Deciphering the role of Paenibacillus strain Q8 in the organic matter recycling in the acid mine drainage of Carnoulès

    Delavat François; Phalip Vincent; Forster Anne; Lett Marie-Claire; Lièvremont Didier

    2012-01-01

    Abstract Background The recycling of the organic matter is a crucial function in any environment, especially in oligotrophic environments such as Acid Mine Drainages (AMDs). Polymer-degrading bacteria might play an important role in such ecosystem, at least by releasing by-products useful for the rest of the community. In this study, physiological, molecular and biochemical experiments were performed to decipher the role of a Paenibacillus strain isolated from the sediment of Carnoulès AMD. R...

  7. From highly polluted Zn-rich acid mine drainage to non-metallic waters: Implementation of a multi-step alkaline passive treatment system to remediate metal pollution

    Macías, Francisco; Caraballo, Manuel A.; Roetting, Tobias Stefan; Pérez López, Rafael; Nieto, José Miguel; Ayora Ibáñez, Carlos

    2012-01-01

    Complete metal removal from highly-polluted acid mine drainage was attained by the use of a pilot multistep passive remediation system. The remediation strategy employed can conceptually be subdivided into a first section where the complete trivalent metal removal was achieved by the employment of a previously tested limestone-based passive remediation technology followed by the use of a novel reactive substrate (caustic magnesia powder dispersed in a wood shavings matrix) obtaining a total d...

  8. The Impacts of Acid Mine Drainage on the Black Creek Watershed, Wise County, Virginia

    Yeager, Jessica Lynn

    2003-01-01

    Black Creek is a small watershed located in Wise County, Virginia, west of the town of Norton. At the time of this survey, the watershed encompassed approximately 929 hectares of mine and forest lands with a small recreational area. Black Creek proper is a third-order stream approximately 6.7 km in length from its headwaters to its confluence with the Powell River in Kent Junction. Black Creek and several of the tributaries within the watershed were previously identified as areas impacted b...

  9. Diminished metal accumulation in riverine fishes exposed to acid mine drainage over five decades.

    Jeffree, Ross A; Markich, Scott J; Twining, John R

    2014-01-01

    Bony bream (Nematalosa erebi) and black catfish (Neosilurus ater) were sampled from the fresh surface waters of the Finniss River in tropical northern Australia, along a metal pollution gradient draining the Rum Jungle copper/uranium mine, a contaminant source for over five decades. Paradoxically, populations of both fish species exposed to the highest concentrations of mine-related metals (cobalt, copper, lead, manganese, nickel, uranium and zinc) in surface water and sediment had the lowest tissue (bone, liver and muscle) concentrations of these metals. The degree of reduction in tissue concentrations of exposed populations was also specific to each metal and inversely related to its degree of environmental increase above background. Several explanations for diminished metal bioaccumulation in fishes from the contaminated region were evaluated. Geochemical speciation modeling of metal bioavailability in surface water showed no differences between the contaminated region and the control sites. Also, the macro-nutrient (calcium, magnesium and sodium) water concentrations, that may competitively inhibit metal uptake, were not elevated with trace metal contamination. Reduced exposure to contaminants due to avoidance behavior was unlikely due to the absence of refugial water bodies with the requisite metal concentrations lower than the control sites and very reduced connectivity at time of sampling. The most plausible interpretation of these results is that populations of both fish species have modified kinetics within their metal bioaccumulation physiology, via adaptation or tolerance responses, to reduce their body burdens of metals. This hypothesis is consistent with (i) reduced tissue concentrations of calcium, magnesium and sodium (macro-nutrients), in exposed populations of both species, (ii) experimental findings for other fish species from the Finniss River and other contaminated regions, and (iii) the number of generations exposed to likely selection pressure

  10. Diminished metal accumulation in riverine fishes exposed to acid mine drainage over five decades.

    Ross A Jeffree

    Full Text Available Bony bream (Nematalosa erebi and black catfish (Neosilurus ater were sampled from the fresh surface waters of the Finniss River in tropical northern Australia, along a metal pollution gradient draining the Rum Jungle copper/uranium mine, a contaminant source for over five decades. Paradoxically, populations of both fish species exposed to the highest concentrations of mine-related metals (cobalt, copper, lead, manganese, nickel, uranium and zinc in surface water and sediment had the lowest tissue (bone, liver and muscle concentrations of these metals. The degree of reduction in tissue concentrations of exposed populations was also specific to each metal and inversely related to its degree of environmental increase above background. Several explanations for diminished metal bioaccumulation in fishes from the contaminated region were evaluated. Geochemical speciation modeling of metal bioavailability in surface water showed no differences between the contaminated region and the control sites. Also, the macro-nutrient (calcium, magnesium and sodium water concentrations, that may competitively inhibit metal uptake, were not elevated with trace metal contamination. Reduced exposure to contaminants due to avoidance behavior was unlikely due to the absence of refugial water bodies with the requisite metal concentrations lower than the control sites and very reduced connectivity at time of sampling. The most plausible interpretation of these results is that populations of both fish species have modified kinetics within their metal bioaccumulation physiology, via adaptation or tolerance responses, to reduce their body burdens of metals. This hypothesis is consistent with (i reduced tissue concentrations of calcium, magnesium and sodium (macro-nutrients, in exposed populations of both species, (ii experimental findings for other fish species from the Finniss River and other contaminated regions, and (iii the number of generations exposed to likely

  11. Assessing the concentration, speciation, and toxicity of dissolved metals during mixing of acid-mine drainage and ambient river water downstream of the Elizabeth Copper Mine, Vermont, USA

    Balistrieri, L.S.; Seal, R.R., II; Piatak, N.M.; Paul, B.

    2007-01-01

    The authors determine the composition of a river that is impacted by acid-mine drainage, evaluate dominant physical and geochemical processes controlling the composition, and assess dissolved metal speciation and toxicity using a combination of laboratory, field and modeling studies. Values of pH increase from 3.3 to 7.6 and the sum of dissolved base metal (Cd + Co + Cu + Ni + Pb + Zn) concentrations decreases from 6270 to 100 ??g/L in the dynamic mixing and reaction zone that is downstream of the river's confluence with acid-mine drainage. Mixing diagrams and PHREEQC calculations indicate that mixing and dilution affect the concentrations of all dissolved elements in the reach, and are the dominant processes controlling dissolved Ca, K, Li, Mn and SO4 concentrations. Additionally, dissolved Al and Fe concentrations decrease due to mineral precipitation (gibbsite, schwertmannite and ferrihydrite), whereas dissolved concentrations of Cd, Co, Cu, Ni, Pb and Zn decrease due to adsorption onto newly formed Fe precipitates. The uptake of dissolved metals by aquatic organisms is dependent on the aqueous speciation of the metals and kinetics of complexation reactions between metals, ligands and solid surfaces. Dissolved speciation of Cd, Cu, Ni and Zn in the mixing and reaction zone is assessed using the diffusive gradients in thin films (DGT) technique and results of speciation calculations using the Biotic Ligand Model (BLM). Data from open and restricted pore DGT units indicate that almost all dissolved metal species are inorganic and that aqueous labile or DGT available metal concentrations are generally equal to total dissolved concentrations in the mixing zone. Exceptions occur when labile metal concentrations are underestimated due to competition between H+ and metal ions for Chelex-100 binding sites in the DGT units at low pH values. Calculations using the BLM indicate that dissolved Cd and Zn species in the mixing and reaction zone are predominantly inorganic

  12. Application of horizontal-flow anaerobic immobilized biomass reactor for bioremediation of acid mine drainage.

    Rodriguez, R P; Vich, D V; Garcia, M L; Varesche, M B A; Zaiat, M

    2016-06-01

    The production of low-pH effluent with sulfate and metals is one of the biggest environmental concerns in the mining industry. The biological process for sulfate reduction has the potential to become a low-cost solution that enables the recovery of interesting compounds. The present study analyzed such a process in a horizontal-flow anaerobic immobilized biomass (HAIB) reactor, employing ethanol as the carbon and energy source. Results showed that a maximal efficiency in the removal of sulfate and ethanol could only be obtained by reducing the applied sulfate load (225.1 ± 38 g m(-3) d(-1)). This strategy led to over 75% of chemical oxygen demand (COD) and sulfate removal. Among the COD/SO4(2-) studied ratios, 0.67 showed the most promising performance. The effluent's pH has naturally remained between 6.8 and 7.0 and the complete oxidation of the organic matter has been observed. Corrections of the influent pH or effluent recirculation did not show any significant effect on the COD and sulfate removal efficiency. Species closely related to strains of Clostridium sp. and species of Acidaminobacter hydrogenomorfans and Fusibacter paucivorans that can be related to the process of sulfate reduction were found in the HAIB reactors when the initial pH was 5 and the COD/SO4(2-) ratio increased to 1.0. PMID:27280606

  13. Novel nickel resistance genes from the rhizosphere metagenome of plants adapted to acid mine drainage

    Mirete, Salvador; González de Figueras, Carolina; González-Pastor, José Eduardo

    2007-01-01

    Metal resistance determinants have traditionally been found in cultivated bacteria. To search for genes involved in nickel resistance, we analyzed the bacterial community of the rhizosphere of Erica andevalensis, an endemic heather which grows at the banks of the Tinto River, a naturally metal-enriched and extremely acidic environment in southwestern Spain. 16S rRNA gene sequence analysis of rhizosphere DNA revealed the presence of members of five phylogenetic groups of Bacteria and the two m...

  14. [Effect of Zn(II) on microbial activity in anaerobic acid mine drainage treatment system with biomass as carbon source].

    Li, Shao-Jie; Chen, Tian-Hu; Zhou, Yue-Fei; Yue, Zheng-Bo; Jin, Jiez; Liu, Chang

    2012-01-01

    In this study, with rape straw as carbon source, anaerobic batch experiments were executed to investigate the effect of Zn (II) on the activity of sulphate reducing bacteria (SRB) in the microbial treatment of simulative acid mine drainage (AMD). The results showed that during the 60 experimental days, when initial Zn2+ concentrations were in the range of 73.7 to 196.8 mg x L(-1), SRB had high culturalbility. At the end of these experiments, pH values rose from initial 5.0 to neutral, about 96% of sulphate was reduced and the concentrations of Zn2+ reduced to 0.05 mg x L(-1). The results of Tessier sequential extraction, field emission scanning electron microscope (FE-SEM) and X-ray diffraction(XRD) showed that Zn was found to be fixed through forming organic and sulphide (mainly sphalerite) compounds. For the experiment with high Zn2+ concentration (262.97 mg x L(-1)), at the end of experiments, pH values dropped from initial 5.0 to 4.0, only 27% of sulphate was only reduced and the concentrations of Zn2+ kept in high range (25 mg x L(-1)), the activity of SRB significantly inhibited. This study indicated that: (1) Rape straw can be used as slow-release carbon source for long-term anaerobic AMD treatment; (2) Rape straw can decrease the toxicity of Zn2+ to SRB through adsorption; (3) In anaerobic AMD treatment system, Zn can be fixed by sulphide minerals with mediation of SRB. PMID:22452225

  15. ADSORPTION OF MANGANESE FROM ACID MINE DRAINAGE EFFLUENTS USING BONE CHAR: CONTINUOUS FIXED BED COLUMN AND BATCH DESORPTION STUDIES

    D. C. Sicupira

    2015-06-01

    Full Text Available AbstractIn the present study, continuous fixed bed column runs were carried out in an attempt to evaluate the feasibility of using bone char for the removal of manganese from acid mine drainage (AMD. Tests using a laboratory solution of pure manganese at typical concentration levels were also performed for comparison purposes. The following operating variables were evaluated: column height, flow rate, and initial pH. Significant variations in resistance to the mass transfer of manganese into the bone char were identified using the Thomas model. A significant effect of the bed height could only be observed in tests using the laboratory solution. No significant change in the breakthrough volume could be observed with different flow rates. By increasing the initial pH from 2.96 to 5.50, the breakthrough volume was also increased. The maximum manganese loading capacity in continuous tests using bone char for AMD effluents was 6.03 mg g-1, as compared to 26.74 mg g-1 when using the laboratory solution. The present study also performed desorption tests, using solutions of HCl, H2SO4, and water, aimed at the reuse of the adsorbent; however, no promising results were obtained due to low desorption levels associated with a relatively high mass loss. Despite the desorption results, the removal of manganese from AMD effluents using bone char as an adsorbent is technically feasible and attends to environmental legislation. It is interesting to note that the use of bone char for manganese removal may avoid the need for pH corrections of effluents after treatment. Moreover, bone char can also serve to remove fluoride ions and other metals, thus representing an interesting alternative material for the treatment of AMD effluents.

  16. Mine Drainage and Oil Sand Water.

    Wei, Xinchao; Wolfe, F Andrew; Li, Yanjun

    2015-10-01

    Mine drainage from the mining of mineral resources (coal, metals, oil sand, or industrial minerals) remains as a persistent environmental problem. This review summarizes the scientific literature published in 2014 on the technical issues related to mine drainage or mine water in active and abandoned coal/hard rock mining sites or waste spoil piles. Also included in this review is the water from oil sand operations. This review is divided into the four sections: 1) mine drainage characterization, 2) prediction and environmental impact, 3) treatment technologies, 4) oil sand water. Many papers presented in this review address more than one aspect and different sections should not be regarded as being mutuallyexclusive or all-inclusive. PMID:26420092

  17. Evaluation of the impact of acid mine drainage on the chemistry and the macrobenthos in the Carolina stream (San Luis, Argentina).

    Tripole, Susana; Gonzalez, Patricia; Vallania, Adriana; Garbagnati, Marcela; Mallea, Miguel

    2006-03-01

    The purpose of this study was to evaluate the impact of acid mine drainage on the chemistry and the macrobenthos of the Carolina stream (San Luis - Argentina). Samples were obtained in the years 1997-1998 at two sites: site C(1), located 200 m upstream of the drainage, and site C(2), located 800 m downstream. The system buffer capacity was evaluated in the non - contaminated site by means of the buffer index calculation. The physico - chemical changes observed as a consequence of the contribution of acid mine drainage (AMD) were: a decreasing of pH and an increase in the ionic concentration, especially sulfate and Fe coming from the oxidation produced by chemiolithotrophic bacteria. The values obtained indicated a low buffer capacity and a high intrinsic vulnerability of the system to resist the impact originated by the AMD, producing a remarkable decreasing of pH of the receiving stream. These changes caused modifications in the original benthic community that was replaced by organisms more tolerant to the acid stress. A reduction in the abundance and in the taxonomic richness of the benthic macroinvertebrates was observed when compared with the reference station. An increase in the proportion of Chironomidae and of Acari and a decrease in the proportion of the remaining taxa were observed. The most sensitive groups were Ephemeroptera, Trichoptera and Mollusca. The community was mostly affected by the following variables: pH, conductivity, sulfate and dissolved total Fe. PMID:16565803

  18. Comparison of benthic macroinvertebrate indices for the assessment of the impact of acid mine drainage on an Irish river below an abandoned Cu-S mine

    A range of macroinvertebrate indices were compared to assess the most appropriate metric for the assessment of acid mine drainage (AMD) in a low alkalinity, highly erosional river in south-east Ireland. Differences were found in the ability of indices to discriminate AMD impact with the Brillouin, BMWP score, Margalef and Shannon Indices the most precise. Taxon richness was also strongly correlated with AMD indicator parameters (e.g. pH alkalinity, sulphate, Zn and Fe) at impacted sites being an equally reliable metric. The response of the community structure to AMD in this river does not fulfil the optimum criteria for either diversity or biological indices, which may explain the variation in the success of different indices seen in this and other studies. The development of indices that model the expected community response to AMD more accurately or are based on the response of indicator species to AMD pollutants are required. - Several indices were suitable for AMD impact assessment, although due to AMD and receiving water variability no single index may be universally reliable

  19. Mineral-microorganism interactions in Acid Mine Drainage environments: preliminary results

    Carbone, Cristina; Zotti, Mirca; Pozzolini, Marina; Giovine, Marco; Di Piazza, Simone; Mariotti, Mauro; Lucchetti, Gabriella

    2014-05-01

    Minerals play a key role in controlling the mobility and distribution of metals and metalloids of environmental concern in supergenic environments. These are involved in a variety of processes, spanning the alteration of primary minerals to the formation of secondary authigenic phases and can represent a source or a trap for Potentially Ecotoxic Elements (PTEs). Soil, sediments, and waters heavily polluted with PTEs through AMD processes are a reservoir of a unusual bacteria and fungi well adapted to these toxic environments. Classical studies of biotic weathering have mainly focused on water-mineral interaction and on the ability of microorganism to influence the soil solution chemical composition. In this work, we analyzed two different representative ochreous and greenish-blue AMD colloidal precipitates in order to i) characterize the biota population present in these colloidal minerals and ii) verify the bioaccumulation of PTEs into the fungi and the potential impact of bacteria in the geochemistry of the system. The samples are composed by nanocrystalline goethite which contains high amounts of Fe, Cu, Zn, Pb, and Ni and woodwardite that is characterized by Cu, Zn, Ni, Y, and Ce. These precipitates were examined in order to evaluate the presence of fungal strains and to extract bacteria DNA. The preliminary results of fungi characterization show an interesting and selected mycobiota able to survive under unfavourable environmental conditions. A significant number of fungal strains was isolated in pure culture. Most of them belong to the genus Mucor and Penicillium. It is worth noting the presence of Trametes versicolor, a macrofungal lignicolous species already known for heavy metal biosorption capability from aqueous solution (Gülay et al 2003). The same colloidal precipitates have been processed to extract bacteria DNA, using a specific procedure developed for DNA extraction from sediments. The results gave a good yield of nucleic acids and the positive PCR

  20. Long term remediation of highly polluted acid mine drainage: A sustainable approach to restore the environmental quality of the Odiel river basin

    During 20 months of proper operation the full scale passive treatment in Mina Esperanza (SW Spain) produced around 100 mg/L of ferric iron in the aeration cascades, removing an average net acidity up to 1500 mg/L as CaCO3 and not having any significant clogging problem. Complete Al, As, Cd, Cr, Cu, Ti and V removal from the water was accomplished through almost the entire operation time while Fe removal ranged between 170 and 620 mg/L. The system operated at a mean inflow rate of 43 m3/day achieving an acid load reduction of 597 g.(m2 day)-1, more than 10 times higher than the generally accepted 40 g.(m2 day)-1 value commonly used as a passive treatment system designing criteria. The high performance achieved by the passive treatment system at Mina Esperanza demonstrates that this innovative treatment design is a simple, efficient and long lasting remediation option to treat highly polluted acid mine drainage. - Highlights: → Novel reactive mixture enable 20 month of high hydraulic conductivity. → Acid load reduction improved 10 times comparing to vertical flow wetland. → High biotic and abiotic iron oxidation and removal. → Complete Al, As, Cd, Cr, Cu, Ti and V water removal. - A high permeable alkaline reactive substrate offers a sustainable option to remediate severely polluted acid mine drainage in the Odiel basin

  1. Tracing the interaction of acid mine drainage with coal utilization byproducts in a grouted mine: Strontium isotope study of the inactive Omega Coal Mine, West Virginia (USA)

    In order to ameliorate acidic discharge, the inactive Omega Coal Mine, West Virginia was partially filled by injection of a grout consisting of 98% coal utilization byproducts (CUB), including fluidized bed combustion ash and fly ash, and 2% Portland cement. In this study, discharge chemistry and Sr isotope ratios were determined to identify and quantify the extent of interaction between mine waters and the CUB-cement grout. Eight sampling sites were monitored around the downdip perimeter of the mine. The major and trace element chemistry of the discharges was generally not sufficient to distinguish between discharges that interacted with grout and those that did not. Elements that showed the most separation include K and As, which were elevated in some waters that interacted with CUB-cement grout. In contrast, the Sr isotope ratios clearly distinguished discharges from grouted and non-grouted areas. Discharges that bypassed the grouted portions had 87Sr/86Sr ratios ranging from 0.71510 to 0.71594, while two discharges that interacted with grout had ratios in the range of 0.71401-0.71456. The Treatment Inlet, which includes both grouted and ungrouted discharges, yielded intermediate isotopic ratios. Leaching experiments on CUB-cement grout, coal and surrounding rocks are consistent with the isotopic trends observed in the discharges. Based on these results, waters that interacted with grout received 30-40% of their Sr from the CUB-cement grout material. These results suggest that the grout material is chemically eroding at a rate of approximately 0.04% per year. This novel application of the Sr isotope system illustrates its ability to sensitively track and quantify fluid interaction with coal and CUB-based grout.

  2. Dissolved inorganic carbon evolution and stable carbon isotope fractionation in acid mine drainage contaminated streams: Insights from a laboratory study

    Samples of groundwater, spring water and stream water contaminated by acid mine drainage (AMD), and uncontaminated stream water were collected and allowed to evolve in contact with air in the laboratory for 15-88 days. The objective of this study was to (1) document temporal changes in dissolved inorganic C (DIC) concentrations and stable isotopic composition (δ13CDIC) and (2) to determine the reaction mechanism and resulting isotopic fractionation (13C/12C) accompanying the chemical evolution of AMD. The contaminated spring and stream samples and one groundwater sample (with no HCO3-) showed temporal decreases in pH, Fe2+, alkalinity, and DIC, and enrichment in δ13CDIC. One contaminated groundwater sample (with HCO3- between 529 and 630 mg/L) showed a temporal increase in pH despite observed decreases in Fe2+, alkalinity and DIC, and enrichment in δ13CDIC. The uncontaminated stream samples showed a continuous temporal increase in pH, relatively constant alkalinity and DIC, and enrichment in δ13CDIC. The results suggest that proton production related to Fe2+ transformation is the driving force for DIC loss in AMD-contaminated samples, and that DIC loss can be described by first order kinetics. The C isotope enrichment rates associated with DIC loss in the contaminated samples varied between 1.0 per mille and 1.8 per mille for stream water, 2.1 per mille and 2.6 per mille for the spring, 1.0 per mille and 1.2 per mille for groundwater with no HCO3-, and 7.6 per mille and 9.3 per mille for groundwater with high HCO3-. Variations in 13C enrichment in the contaminated samples are attributed to differences in the initial Fe2+:HCO3- ratio. The effect of proton production on 13C enrichment in the AMD-contaminated samples was modeled as a Rayleigh-type distillation, whereby isotope fractionation was constant and occurred in an 'equilibrium closed system'. In the uncontaminated stream samples, C exchange between DIC and atmospheric CO2 resulted in an overall enrichment

  3. Using environmental isotopes to characterize hydrologic processes of the Nelson Tunnel acid mine drainage site, West Willow Creek watershed, Creede, CO

    Krupicka, A.; Williams, M. W.

    2010-12-01

    Acid mine drainage continues to be a pressing ecological issue across the Mountain West. Traditional remediation strategies usually involve the installation of an expensive and unsightly “end-of-pipe” water treatment plant without a full understanding of the overall hydrology of the system. In this study we show how applying water chemistry techniques to investigate water sources, ages, flow paths and residence times in a watershed affected by acid mine drainage can lead to alternative, less expensive methods of reclamation. We use both radiogenic (3H and 14C) and stable (18O and D) environmental isotopes to age waters and characterize the level of surface and groundwater interaction. Tritium content for waters collected in the tunnel was largely found to be 0-3 TU, indicating an age of greater than 50 years. This was supported by 14C values of DIC in tunnel samples that indicated ages and a hydraulic residence time on the order of hundreds to thousands of years. Stable isotopes 18O and D plotted closely to the Global Meteoric Water Line (GMWL). Combined with the heavy faulting and dominant welded volcanic tuffs of the region, this all indicates a system with very little surface-ground water interaction and a long, deep, likely channelized flow path. A future up-gradient pumping test would help confirm these findings and further elucidate the location and mechanism of the system’s primary recharge to the mine workings.

  4. Major and trace-element analyses of acid mine waters in the Leviathan Mine drainage basin, California/Nevada; October, 1981 to October, 1982

    Ball, J.W.; Nordstrom, D.K.

    1985-01-01

    Water issuing from the inactive Leviathan open-pit sulfur mine has caused serious degradation of the water quality in the Leviathan/Bryant Creek drainage basin which drains into the East Fork of the Carson River. As part of a pollution abatement project of the California Regional Water Quality Control Board, the U.S. Geological Survey collected hydrologic and water quality data for the basin during 1981-82. During this period a comprehensive sampling survey was completed to provide information on trace metal attenuation during downstream transport and to provide data for interpreting geochemical processes. This report presents the analytical results from this sampling survey. Sixty-seven water samples were filtered and preserved on-site at 45 locations and at 3 different times. Temperature, discharge, pH, and Eh and specific conductance were measured on-site. Concentrations of 37 major and trace constituents were determined later in the laboratory on preserved samples. The quality of the analyses was checked by using two or more techniques to determine the concentrations including d.c.-argon plasma emission spectrometry (DCP), flame and flameless atomic absorption spectrophotometry, UV-visible spectrophotometry, hydride-generation atomic absorption spectrophotometry and ion chromatography. Additional quality control was obtained by comparing measured to calculated conductance, comparing measured to calculated Eh (from Fe-2 +/Fe-3+ determinations), charge balance calculations and mass balance calculations for conservative constituents at confluence points. Leviathan acid mine waters contain mg/L concentrations of As, Cr, Co, Cu, Mn, Ni, T1, V and Zn, and hundreds to thousands of mg/L concentrations of Al, Fe, and sulfate at pH values as low as 1.8. Other elements including Ba, B, Be, Bi, Cd , Mo, Sb, Se and Te are elevated above normal background concentrations and fall in the microgram/L range. The chemical and 34 S/32 S isotopic analyses demonstrate that these

  5. Three-year survey of sulfate-reducing bacteria community structure in Carnoules acid mine drainage (France), highly contaminated by arsenic

    Giloteaux, L.; Duran, R.; Casiot, C.; Bruneel, Odile; Elbaz-Poulichet, F.; Goni-Urriza, M.

    2013-01-01

    A 3-year survey on sulfate-reducing bacteria (SRB) was conducted in the waters of the arsenic-rich acid mine drainage (AMD) located at Carnoules (France) to determine the influence of environmental parameters on their community structure. The source (S5 station) exhibited most extreme conditions with pH lowering to similar to 1.2; iron, sulfate, and arsenic concentrations reaching 6843, 29593, and 638mgL1, respectively. The conditions were less extreme at the downstream stations S1 (pH simila...

  6. The study of rare earth elements in farmer's well waters of the Podwiśniówka acid mine drainage area (south-central Poland)

    Migaszewski, Zdzisław M.; Gałuszka, Agnieszka; Migaszewski, Andrzej

    2013-01-01

    The principal objective of the current study was to elucidate the potential influence of acid mine drainage (AMD) pond on neighboring farmer's wells in the Podwiśniówka area (south-central Poland), using North American Shale Composite (NASC)-normalized rare earth element (REE) concentration profiles. The well waters generally displayed a distinctly positive Eu anomaly similar to that of parent rocks and AMD sediment. In contrast, the AMD pit pond water exhibited the typical roof-shaped NASC-n...

  7. Thiomonas sp. CB2 is able to degrade urea and promote toxic metal precipitation in acid mine drainage waters supplemented with urea

    Farasin, Julien; Andres, Jérémy; Casiot, Corinne; Barbe, Valérie; Faerber, Jacques; Halter, David; Heintz, Dimitri; Koechler, Sandrine; Lièvremont, Didier; Lugan, Raphael; Marchal, Marie; Plewniak, Frédéric; Seby, Fabienne; Bertin, Philippe N; Arsène-Ploetze, Florence

    2015-01-01

    The acid mine drainage (AMD) in Carnoulès (France) is characterized by the presence of toxic metals such as arsenic. Several bacterial strains belonging to the Thiomonas genus, which were isolated from this AMD, are able to withstand these conditions. Their genomes carry several genomic islands (GEIs), which are known to be potentially advantageous in some particular ecological niches. This study focused on the role of the “urea island” present in the Thiomonas CB2 strain, which carry the gen...

  8. Hydrogeology and geochemistry of acid mine drainage in ground water in the vicinity of Penn Mine and Camanche Reservoir, Calaveras County, California. Summary report, 1993--1995

    Alpers, C.N.; Hamlin, S.N.; Hunerlach, M.P.

    1999-06-01

    The report presents results from the ground-water investigation at the Penn Mine by the US Geological Survey from October 1991 to April 1995. The specific objectives of the investigation were to evaluate (1) the quantity and quality of ground water flowing toward Camanche Reservoir from the Penn Mine area; (2) the ground-water transport of metals, sulfate, and acidity between Mine Run and Camanche Reservoirs; and (3) the hydrologic interactions between the flooded mine workings and other ground water and surface water in the vicinity.

  9. Zinc and nickel removal in limestone based treatment of acid mine drainage: The relative role of adsorption and co-precipitation

    Highlights: • Limestone treatment of mining impacted water was simulated in batch reactors. • Zinc and nickel removals were quantified/characterized with a sequential extraction. • Removals were described with a surface complexation and a surface precipitation model. • Extraction/modeling results imply mechanisms beyond adsorption dominate metal removal. - Abstract: Mining influenced water may contain high metal and sulfate loads, and have low pH (acid mine drainage). Removal of these metals prior to environmental discharge is critical to maintain ecosystem vitality. Limestone based passive treatment systems are commonly used for pH neutralization. The same conditions that lead to pH neutralization may also remove a substantial amount of metals from solution, but the connection between treatment conditions and metal removal are not well understood. In this study, zinc and nickel removals are quantified in batch reactor simulated limestone treatment of acid mine drainage. The resulting solid phase is characterized with a sequential extraction procedure, and the removals are interpreted using surface complexation and surface precipitation models. Zinc and nickel removals are closely linked to the initial iron concentration in the mine water, but are also affected by pH, alkalinity, calcium and sulfate concentrations. The surface complexation model was based on literature descriptions of hydrous ferric oxide. In order to obtain a sufficient fit to the data, the surface site density was increased to an unrealistically high value. Uptake data was also fit to an existing surface precipitation model. The values used are similar to those found in previous studies. Both models indicate that adsorption is not the dominant removal process in the treatment system. Using adsorption only models will generally underpredict metal removals within limestone based treatment systems

  10. Geochemistry of the Obey River Basin, north-central Tennessee: a case of acid mine water in the Karst drainage system

    The East Fork of the Obey River, a tributary of the Cumberland River, drains a 523 km2 basin along the western margin of the Cumberland Plateau. The upper basin lies on clastic rocks that include coals that were mined earlier in this century. The lower basin is drained through a deep gorge where the East Fork has cut downward into the Mississippian carbonate rocks. The lower basin is karstic, with a 9 km length of the river and most of its tributaries underdrained by conduit systems. Many of the upper basin tributaries of the East Fork are contaminated by acid mine drainage and have high levels of acidity, sulfate, iron and aluminium. As the acid mine waters sink in the limestone portions of the basin, they are buffered but acidity is not rapidly reduced and acid water appears at a large spring deep in the karst having survived 5 km of transport. Sulfate waters gradually convert to bicarbonate waters as more tributaries from carbonate rocks enter the system. Aluminium in solution decreases with increasing pH, and precipitates as colloidal sized particles. Although alkalinity increases in the lower reaches of the basin, most of the waters remain highly undersaturated with respect to calcite

  11. Diversity of Microorganisms in Fe-As-Rich Acid Mine Drainage Waters of Carnoulès, France

    Bruneel, O.; Duran, R.; Casiot, C.; Elbaz-Poulichet, F.; Personné, J.-C.

    2006-01-01

    The acid waters (pH 2.7 to 3.4) originating from the Carnoulès mine tailings contain high concentrations of dissolved arsenic (80 to 350 mg · liter−1), iron (750 to 2,700 mg · liter−1), and sulfate (2,000 to 7,500 mg · liter−1). During the first 30 m of downflow in Reigous creek issuing from the mine tailings, 20 to 60% of the dissolved arsenic is removed by coprecipitation with Fe(III). The microbial communities along the creek have been characterized using terminal-restriction fragment leng...

  12. Influence of Acid Mine Drainage (AMD) on recent phyto- and zooplankton in "the Anthropogenic Lake District" in south-west Poland

    Sienkiewicz, Elwira; Gasiorowski, Michal

    2015-04-01

    In south-west Poland (central Europe) many the post-mining lakes formed so-called "the Anthropogenic Lake District". Areas, where water comes in contact with lignite beds characterized by high concentration of sulfide minerals are called Acid Mine Drainage (AMD). Pyrite oxidation and other sulfide compounds caused release sulfuric acids and heavy metal ions. These processes caused decline of water pH, sometimes to extremely low pH AMD we analyzed recent diversity of diatoms and Cladocera remains and water chemistry from extremely acidic, relatively young lakes and from alkaline, older water bodies. As we expected, flora and fauna from acidic lakes have shown very low diversity and species richness. Among diatoms, Eunotia exigua (Bréb. ex Kütz.) Rabenhorst and/or E. paludosa Grunow were dominated taxa, while fauna Cladocera did not occurred in lakes with water pH < 3. On this area, exploitation of lignite continued up to 1973. Older lakes were formed in the region where the mine started work in 1880 and lignite mining stopped in 1926. Measurements of pH value in situ point to neutral or alkaline water, but because of the possibility of hysteresis phenomenon, the studies of phyto- and zooplankton have shown if there has already been a widespread neutralization of lake ecosystems, what encompassing both recovery of water chemistry and rebuilding of biota communities. Studies have confirmed, that phyto- and zooplankton living nowadays in lakes located on this area, where exploitation of lignite ended at the beginning of 20th century, indicate completely recovery from acidification caused by coal mine activities. Presently, the lakes were dominated by planktonic diatoms and Cladocera taxa, such as Discostella pseudostelligera (Hust.) Houk & Klee and Bosmina longirostris, respectively.

  13. Drainage from coal mines: Chemistry and environmental problems

    Much of the research on coal-mine drainage chemistry was conducted a decade ago, and now increased environmental awareness has brought about renewed interest in the findings. Consideration of the trace minerals and elements in coal points to the possible generation of acidic waters upon weathering, especially when pyrite is present. When pyrite weathers, it produces H+ and Fe3+ which catalyze the incongruent weathering of other carbonates and sulfides. In this weathering mechanism, catalysis by bacteria is important. Of the environmental problems in coal mine drainage, the mineral acidity of the water is the most serious. This is caused not only by the H+, but also by Mn4+, Fe3+, and Al3+ that are found or generated within the drainage. Case studies in Kentucky, Pennsylvania, Illinois, and Colorado show that the abundance and form of pyrite in the deposit and in the overburden determines the level of acidity and the concentration of heavy metal pollutants in the drainage. Recent trends in environmental enforcement that emphasize integrated stream water standards and biotoxicity assays point to the possibility that the concentrations of heavy metals in coal mine drainages may cause environmental concern

  14. Treatment of acid mine wastewaters

    Acid mine drainage often results from the oxidation sulfide minerals to form sulfuric acid. As a consequence, high concentrations of metals in the both the suspended and dissolved state result from the low pH water. This paper discusses several of the more common treatment methods for acid mine drainage including the use of chemical precipitation agents, pH correction agents, filtration methods, and biodegradation methods. Advanced treatment technologies are also briefly described and include microfiltration, reverse osmosis, ion exchange, and electrodialysis

  15. Metal partitioning in sediments and mineralogical controls on the acid mine drainage in Ribeira da Água Forte (Aljustrel, Iberian Pyrite Belt, Southern Portugal)

    This work focuses on the geochemical processes taking place in the acid drainage in the Ribeira da Água Forte, located in the Aljustrel mining area in the Iberian Pyrite Belt. The approach involved water and stream sediment geochemical analyses, as well as other techniques such as sequential extraction, Mössbauer spectroscopy, and X-ray diffraction. Ribeira da Água Forte is a stream that drains the area of the old mine dumps of the Aljustrel mine, which have for decades been a source of acid waters. This stream flows to the north for a little over than 10 km, but mixes with a reduced, organic-rich, high pH waste water from the municipal waste water pools of the village. This water input produces two different results in the chemistry of the stream depending upon the season: (i) in the winter season, effective water mixing takes place, and the flux of acid water from the mine dumps is continuous, resulting in the immediate precipitation of the Fe from the acid waters; (ii) during the summer season, acid drainage is interrupted and only the waste water feeds the stream, resulting in the reductive dissolution of Fe hydroxides and hydroxysulfates in the stream sediments, releasing significant quantities of metals into solution. Throughout the year, water pH stays invariably within 4.0–4.5 for several meters downstream of this mixing zone even when the source waters come from the waste water pools, which have a pH around 8.4. The coupled interplay of dissolution and precipitation of the secondary minerals (hydroxides and sulfates), keeps the system pH between 3.9 and 4.5 all along the stream. In particular, evidence suggests that schwertmannite may be precipitating and later decomposing into Fe hydroxides to sustain the stream water pH at those levels. While Fe content decreases by 50% from solution, the most important trace metals are only slightly attenuated before the solution mixes with the Ribeira do Rôxo stream waters. Concentrations of As are the only ones

  16. Acid rock drainage in the uranium mining and milling site of Pocos de Caldas, Brazil -- duration assessment, pollutant generation modelling and remediation strategies

    This geochemical modeling work was carried out to simulate the acid drainage generation from one of the waste-rock piles at the Pocos de Caldas uranium mining site. The mathematical code STEADQYL was used. The estimated results were in good agreement for sulphate and uranium concentrations and the duration of the acid water generation was estimated to be about 500 years. The effect of covering the dump with a material that minimized oxygen diffusion was assessed. Projections indicated that covering the dump with a 1.0 m thickness of a material (like clay), which had an oxygen diffusion coefficient of 109m2·s1, would reduce the pollutant concentrations to acceptable values. The estimated cost, when using this strategy, would be about US $10 million. (author)

  17. A method to mitigate acid-mine drainage in the Shamokin area, Pennsylvania, U.S.A

    The three anthracite coal fields of eastern Pennsylvania occur in large synclinal basins surrounded by sandstone hogback ridges. The streams draining the coal regions are heavily contaminated by sulfuric acid due to the weathering of pyrite in the abandoned mines and culm. Dams could be built in the water gaps of the streams leaving the basins, forming huge reservoirs. For example, in the western part of the Middle Coal Field (Shamokin-Mt. Carmel area), the construction of four dams would form a reservoir that would inundate practically all the culm banks, abandoned mines, and environmentally abused lands in this coal field. The reservoir would be approximately 140 sq km in area and could be the source of water for pumped-storage hydroelectricity generation. The water should have moderately good quality and could serve the recreational needs of a vast population of the Middle Atlantic states

  18. Heavy metals removal from acid mine drainage water using biogenic hydrogen sulphide and effluent from anaerobic treatment: Effect of pH

    Jimenez-Rodriguez, A.M. [Departamento de Sistemas Fisicos, Quimicos y Naturales, Facultad de Ciencias Ambientales, Universidad Pablo de Olavide. Carretera de Utrera, km 1. 41013 Sevilla (Spain); Duran-Barrantes, M.M. [Departamento de Ingenieria Quimica, Facultad de Quimica, Universidad de Sevilla, C/Profesor Garcia Gonzalez, s/n, 41071 Sevilla (Spain); Borja, R., E-mail: rborja@cica.es [Consejo Superior de Investigaciones Cientificas (CSIC), Instituto de la Grasa, Avda. Padre Garcia Tejero 4, 41012 Sevilla (Spain); Sanchez, E.; Colmenarejo, M.F. [Consejo Superior de Investigaciones Cientificas (CSIC), Centro de Ciencias Medioambientales, C/Serrano, 115-duplicado, 28006 Madrid (Spain); Raposo, F. [Consejo Superior de Investigaciones Cientificas (CSIC), Instituto de la Grasa, Avda. Padre Garcia Tejero 4, 41012 Sevilla (Spain)

    2009-06-15

    Four alternatives (runs A, B, C and D) for heavy metals removal (Fe, Cu, Zn and Al) from acid mine drainage water (AMDW) produced in the mining areas of the Huelva Province, Spain, were evaluated. In run A, the anaerobic effluent from the treatment of acid mine drainage water (cheese whey added as a source of carbon) was mixed with the raw AMDW. The pH increased to 3.5 with the addition of KOH. In run B, biogas with around 30% of hydrogen sulphide obtained in the anaerobic reactor was sparged to the mixture obtained in run A, but in this case at a pH of 5.5. In run C, the pH of the raw AMDW was increased to 3.5 by the addition of KOH solution. Finally, in run D, the pH of the raw AMDW was increased to 5.5 by the addition of KOH solution and further biogas was sparged under the same conditions as in run A. It was found that heavy metal removal was a function of pH. At a pH of 3.5 most of the iron was removed while Zn and Cu were partially removed. At a pH of 5.5 the removal of all metals increased considerably. The best results were obtained in run B where the percentages of removal of Fe, Cu, Zn and Al achieved values of 91.3, 96.1, 79.0 and 99.0%, respectively. According to the experimental results obtained tentative schemas of the flow diagram of the processes were proposed.

  19. Heavy metals removal from acid mine drainage water using biogenic hydrogen sulphide and effluent from anaerobic treatment: Effect of pH

    Four alternatives (runs A, B, C and D) for heavy metals removal (Fe, Cu, Zn and Al) from acid mine drainage water (AMDW) produced in the mining areas of the Huelva Province, Spain, were evaluated. In run A, the anaerobic effluent from the treatment of acid mine drainage water (cheese whey added as a source of carbon) was mixed with the raw AMDW. The pH increased to 3.5 with the addition of KOH. In run B, biogas with around 30% of hydrogen sulphide obtained in the anaerobic reactor was sparged to the mixture obtained in run A, but in this case at a pH of 5.5. In run C, the pH of the raw AMDW was increased to 3.5 by the addition of KOH solution. Finally, in run D, the pH of the raw AMDW was increased to 5.5 by the addition of KOH solution and further biogas was sparged under the same conditions as in run A. It was found that heavy metal removal was a function of pH. At a pH of 3.5 most of the iron was removed while Zn and Cu were partially removed. At a pH of 5.5 the removal of all metals increased considerably. The best results were obtained in run B where the percentages of removal of Fe, Cu, Zn and Al achieved values of 91.3, 96.1, 79.0 and 99.0%, respectively. According to the experimental results obtained tentative schemas of the flow diagram of the processes were proposed.

  20. Long-range downstream effects of urban runoff and acid mine drainage in the Debed River, Armenia: insights from lead isotope modeling

    Lead concentrations and isotopic compositions measured along 80 km of the Debed River in the Republic of Armenia provide new insights into the geochemical and physical controls on riparian Pb transport by allowing comparison of the long-range, downstream impacts of acid mine drainage with runoff from an industrialized city. The modern background Pb concentration in Armenian surface waters is estimated to be ∼0.01 μg/L, based on analyses of remote alpine rivers in Armenia. The lead concentration in the Debed River is 8 μg/L (800 times background) after passing through Vanadzor, the second largest industrial city in Armenia; it then decreases to 1 μg/L before the Debed River flows into the Alaverdi mining district. There, the Debed River receives waters from two mining drainage streams with Pb concentrations >3000 μg/L, but those concentrations decrease 3 orders of magnitude to ∼3 μg/L by the time the river exits Armenia and flows into the Republic of Georgia. Isotope mixing plots show shifts in Pb isotope composition as the river flows out of Vanadzor, evidencing the mixture of an average terrestrial Pb composition (206Pb/207Pb ∼ 1.17; 208Pb/207Pb ∼ 2.45) with past leaded gasoline and other industrial Pb emissions retained in the river's sediments within that region (208Pb/207Pb ≤ 2.45). The isotopic composition again shifts (e.g., 208Pb/207Pb ≥ 2.46) as the river passes through the Alaverdi mining district, where isotopic ratios in the water are characteristic of Pb in the area's massive sulfide deposits. Modeling both downstream elemental concentrations and Pb isotopic compositions further resolves the physical and chemical behavior of the contaminants in the river system. A multi-element model of concentration gradients in the acid mine drainage streams indicates Pb is attenuated by Al(OH)3 precipitation (54% of the loss) and by adsorption onto other particles settling out of the water column (46% of the loss). Modeling of Pb transport in the

  1. Range of drainage effect of surface mines

    Sozanski, J.

    1978-03-01

    This paper discusses methods of calculating the range of effects of water drainage from surface coal mines and other surface mines. It is suggested that methods based on test pumping (water drainage) are time consuming, and the results can be distorted by atmospheric factors such as rain fall or dry period. So-called empirical formulae produce results which are often incorrect. The size of a cone shaped depression calculated on the basis of empirical formulae can be ten times smaller than the size of the real depression. It is suggested that using a formula based on the Dupuit formula is superior to other methods of depression calculation. According to the derived formulae the radius of the depresion cone is a function of parameters of the water bearing horizons, size of surface mine working and of water depression. The proposed formula also takes into account the influence of atmospheric factors (water influx caused by precipitation, etc.). (1 ref.) (In Polish)

  2. Feasibility study of a self-remediation system for mine drainage using its thermal energy

    Oh, Chamteut; Cheong, Youngwook; Yim, Giljae; Ji, Sangwoo

    2016-04-01

    Mine drainage is defined as the water which is discharged to the ground surface through shafts and/or cracks formed by mining activities. Typically, mine drainage features high concentration of acidity and metals since it passes through the underground. Therefore, for the purpose of protecting the surrounding natural environment, mine drainage should be remediated before being discharged to nature. Mine drainage, due to its nature of being retained underground, shows constant temperature which is independent from the temperature of the atmosphere above ground. This condition allows mine drainage to become a promising renewable energy source since energy can be recovered from water with constant temperature. In this research, a self-remediation system is proposed which remediates the mine drainage through electrochemical reactions powered by the thermal energy of mine drainage. High energy efficiency is able to be achieved by shortening the distance between the energy source and consumption, and therefore, this system has a strong advantage to be actualized. A feasibility study for the system was conducted in this research where the thermal energy of mine drainage over time and depth was calculated as energy supply and the required electrical energy for remediating the mine drainage was measured as energy consumption. While the technology of converting thermal energy directly into electrical energy is yet to be developed, energy balance analysis results showed that the proposed self-remediation system is theoretically possible.

  3. Determination of in situ speciation of manganese in treated acid mine drainage water by using multiple diffusive gradients in thin films devices

    Graphical abstract: -- Highlights: •In situ speciation of Mn by using multiple DGT devices was evaluated. •Chelex resin, DE81 and P81 membranes were used as binding phases in the DGT devices. •The proposed approach was applied to analyze treated acid mine drainage. •Good results were found for speciation of Mn in site containing −1. DGT speciation were in agreement with speciation by software and by on site SPE. -- Abstract: Acid mine drainage (AMD) is a serious environmental problem that creates acidic solution with high Mn concentrations. The speciation of residual Mn from AMD after an active treatment involving the addition of a neutralizing agent can reliably evaluate the treatment efficiency and provide knowledge of the Mn species being inputted into the environment. The aim of this study was to evaluate the in situ lability and speciation of Mn using the diffusive gradients in thin films (DGT) technique with treated drainage water from a uranium mine (TAMD). DGT devices with different binding phases (Chelex-100 and P81 and DE81membranes) were used to perform the in situ speciation of Mn. A comparison of the results from deploying DGT in the laboratory and in situ shows that the speciation of Mn in TAMD should be performed in situ. Linear deployment curves (from in situ experiments) indicate that the DGT device containing the Chelex-100 binding phase can be used to evaluate Mn lability in TAMD. The labile Mn fraction (from in situ measurements) obtained using the device containing the Chelex-100 resin ranged from 63 to 81% of the total Mn concentration and, when compared to the speciation obtained using the CHEAQS software, indicated that this device was capable of uptaking the free Mn2+ and a portion of the MnSO4(aq). The values obtained using the DGT technique were compared to those from on site solid phase extraction, and a good agreement was found between the results. The amount of negative Mn species sampled by DE81 device was insignificant (

  4. Disposal of fluidized bed combustion ash in an underground mine to control acid mine drainage and subsidence - phase II - small scale field demonstration. Topical report, December 1, 1996--February 28, 1997

    Ziemkiewicz, P.F.; Head, W.J.; Gray, D.D.; Siriwardane, H.J.; Sack, W.A.

    1998-01-01

    It has been proposed that a mix made from fly and bottom ash from atmospheric pressure fluidized bed coal combusters (FBC ash), water, and stabilizers be injected from the surface into abandoned room and pillar coal mines through boreholes. Besides ash disposal, this process would prevent subsidence and acid mine drainage. Such a mix (called `grout`) needs to be an adequately stable and flowable suspension for it to spread and cover large areas in the mine. This is necessary as the drilling of the boreholes will be an expensive operation and the number such holes should be minimized. Addition of bentonite was found to be needed for this purpose. A suitable grout mix was tested rheologically to determine its fluid flow properties. Finding little published information on such materials, tests were performed using a commercial rotational viscometer with a T-bar rotor and a stand which produced a helical rotor path. Existing mixer viscometer test methods were modified and adapted to convert the measurements of torque vs. angular speed to the material properties appearing in several non-Newtonian constitutive equations. Yield stress was measured by an independent test called the vane method. The rheological behavior was a close fit to the Bingham fluid model. Bleed tests were conducted to ascertain the stability of the mixtures. Spread tests were conducted to compare the flowability of various mixes. Using the flow parameters determined in the laboratory, numerical simulations of grout flow were performed and compared with the results of scale model and field tests. A field injection of this grout was performed at the Fairfax mines in Preston county, W.V.. The observations there proved that this FBC ash grout flows as desired, is a very economical way of disposing the environmentally menacing ash, while also preventing the subsidence and acid mine drainage of the mines.

  5. High-frequency, long-duration water sampling in acid mine drainage studies: a short review of current methods and recent advances in automated water samplers

    Chapin, Thomas

    2015-01-01

    Hand-collected grab samples are the most common water sampling method but using grab sampling to monitor temporally variable aquatic processes such as diel metal cycling or episodic events is rarely feasible or cost-effective. Currently available automated samplers are a proven, widely used technology and typically collect up to 24 samples during a deployment. However, these automated samplers are not well suited for long-term sampling in remote areas or in freezing conditions. There is a critical need for low-cost, long-duration, high-frequency water sampling technology to improve our understanding of the geochemical response to temporally variable processes. This review article will examine recent developments in automated water sampler technology and utilize selected field data from acid mine drainage studies to illustrate the utility of high-frequency, long-duration water sampling.

  6. Spatio-Temporal Detection of the Thiomonas Population and the Thiomonas Arsenite Oxidase Involved in Natural Arsenite Attenuation Processes in the Carnoulès Acid Mine Drainage.

    Hovasse, Agnès; Bruneel, Odile; Casiot, Corinne; Desoeuvre, Angélique; Farasin, Julien; Hery, Marina; Van Dorsselaer, Alain; Carapito, Christine; Arsène-Ploetze, Florence

    2016-01-01

    The acid mine drainage (AMD) impacted creek of the Carnoulès mine (Southern France) is characterized by acid waters with a high heavy metal content. The microbial community inhabiting this AMD was extensively studied using isolation, metagenomic and metaproteomic methods, and the results showed that a natural arsenic (and iron) attenuation process involving the arsenite oxidase activity of several Thiomonas strains occurs at this site. A sensitive quantitative Selected Reaction Monitoring (SRM)-based proteomic approach was developed for detecting and quantifying the two subunits of the arsenite oxidase and RpoA of two different Thiomonas groups. Using this approach combined with FISH and pyrosequencing-based 16S rRNA gene sequence analysis, it was established here for the first time that these Thiomonas strains are ubiquitously present in minor proportions in this AMD and that they express the key enzymes involved in natural remediation processes at various locations and time points. In addition to these findings, this study also confirms that targeted proteomics applied at the community level can be used to detect weakly abundant proteins in situ. PMID:26870729

  7. Preliminary evaluation of acid mine drainage in Minas Gerais State, Brazil Avaliação preliminar de drenagem ácida no estado de Minas Gerais, Brasil

    Jaime Wilson Vargas de Mello

    2006-04-01

    Full Text Available Mining in the State of Minas Gerais-Brazil is one of the activities with the strongest impact on the environment, in spite of its economical importance. Amongst mining activities, acid drainage poses a serious environmental problem due to its widespread practice in gold-extracting areas. It originates from metal-sulfide oxidation, which causes water acidification, increasing the risk of toxic element mobilization and water resource pollution. This research aimed to evaluate the acid drainage problem in Minas Gerais State. The study began with a bibliographic survey at FEAM (Environment Foundation of Minas Gerais State to identify mining sites where sulfides occur. Substrate samples were collected from these sites to determine AP (acidity potential and NP (neutralization potential. The AP was evaluated by the procedure of the total sulfide content and by oxygen peroxide oxidation, followed by acidity titration. The NP was evaluated by the calcium carbonate equivalent. Petrographic thin sections were also mounted and described with a special view to sulfides and carbonates. Based on the chemical analysis, the acid-base accounting (ABA was determined by the difference of AP and NP, and the acid drainage potential obtained by the ABA value and the total volume of material at each site. Results allowed the identification of substrates with potential to generate acid drainage in Minas Gerais state. Altogether these activities represent a potential to produce between 3.1 to 10.4 billions of m³ of water at pH 2 or 31.4 to 103.7 billions of m³ of water at pH 3. This, in turn, would imply in costs of US$ 7.8 to 25.9 millions to neutralize the acidity with commercial limestone. These figures are probably underestimated because some mines were not surveyed, whereas, in other cases, surface samples may not represent reality. A more reliable state-wide evaluation of the acid drainage potential would require further studies, including a larger number of

  8. An investigation of Acid Rock Drainage (ARD occurrence in a gold mine located in a Southeastern Brazil region

    Luciana Xavier de Lemos Capanema

    2003-07-01

    Full Text Available This work is aimed at evaluating the potential of Acid Rock Drainage (ARD from two Brazilian gold sulfidic ore samples, by means of using three of the most traditional ARD prediction techniques: Standard Acid Base Accounting and Modified Acid Base Accounting, as static methods, and humidity cells, as a kinetic method. Samples were submitted to chemical and mineralogical characterization that indicated the presence of traces of sulfide minerals, such as pyrite, arsenopyrite, pyrrhotite and of carbonates, calcite and dolomite. While the Standard ABA results were inconclusive, the Modified ABA NNP results and NP/AP ratio suggested a tendency of TP01 and WP01 being acid generators, this tendency being slightly stronger for sample WP01. So, a kinetic test was conducted to elucidate the results. The humidity cells results for samples TP01 and WP01 indicated the probable sulfide oxidation to produce acid, subsequently neutralized by alkalinity generated by the carbonates. Based on the results, one can conclude that although sample WP01 has a slightly higher ARD generation potential than TP01, these samples can be at different stages of ARD process, or better, TP01 is at a more advanced stage of ARD production than WP01. The determinant role of the kinetic tests is highlighted by the results.Esse trabalho tem como objetivo avaliar o potencial de geração de Drenagem Ácida de Rocha (ARD de duas amostras de minério de ouro sulfetado através de três das mais tradicionais técnicas de diagnóstico de ARD: "Standard Acid Base Accounting and Modified Acid Base Accounting", métodos estáticos, e células úmidas, método cinético. As amostras foram submetidas a uma caracterização química e mineralógica que indicou a presença de traços de sulfetos, tais como pirita, arsenopirita e pirrotita e de carbonatos, tais como calcita e dolomita. Considerando os resultados dos ensaios realizados, foi confirmada a necessidade de se utilizarem diversas t

  9. Characterization of limestone reacted with acid-mine drainage in a pulsed limestone bed treatment system at the Friendship Hill National Historical Site, Pennsylvania, USA

    Hammarstrom, J.M.; Sibrell, P.L.; Belkin, H.E.

    2003-01-01

    Armoring of limestone is a common cause of failure in limestone-based acid-mine drainage (AMD) treatment systems. Limestone is the least expensive material available for acid neutralization, but is not typically recommended for highly acidic, Fe-rich waters due to armoring with Fe(III) oxyhydroxide coatings. A new AMD treatment technology that uses CO2 in a pulsed limestone bed reactor minimizes armor formation and enhances limestone reaction with AMD. Limestone was characterized before and after treatment with constant flow and with the new pulsed limestone bed process using AMD from an inactive coal mine in Pennsylvania (pH = 2.9, Fe = 150 mg/l, acidity = 1000 mg/l CaCO3). In constant flow experiments, limestone is completely armored with reddish-colored ochre within 48 h of contact in a fluidized bed reactor. Effluent pH initially increased from the inflow pH of 2.9 to over 7, but then decreased to 6 during operation. Limestone removed from a pulsed bed pilot plant is a mixture of unarmored, rounded and etched limestone grains and partially armored limestone and refractory mineral grains (dolomite, pyrite). The ???30% of the residual grains in the pulsed flow reactor that are armored have thicker (50- to 100-??m), more aluminous coatings and lack the gypsum rind that develops in the constant flow experiment. Aluminium-rich zones developed in the interior parts of armor rims in both the constant flow and pulsed limestone bed experiments in response to pH changes at the solid/solution interface. ?? 2003 Elsevier Ltd. All rights reserved.

  10. Microbial reduction of ferric iron oxyhydroxides as a way for remediation of grey forest soils heavily polluted with toxic metals by infiltration of acid mine drainage

    Georgiev, Plamen; Groudev, Stoyan; Spasova, Irena; Nicolova, Marina

    2015-04-01

    The abandoned uranium mine Curilo is a permanent source of acid mine drainage (AMD) which steadily contaminated grey forest soils in the area. As a result, the soil pH was highly acidic and the concentration of copper, lead, arsenic, and uranium in the topsoil was higher than the relevant Maximum Admissible Concentration (MAC) for soils. The leaching test revealed that approximately half of each pollutant was presented as a reducible fraction as well as the ferric iron in horizon A was presented mainly as minerals with amorphous structure. So, the approach for remediation of the AMD-affected soils was based on the process of redoxolysis carried out by iron-reducing bacteria. Ferric iron hydroxides reduction and the heavy metals released into soil solutions was studied in the dependence on the source of organic (fresh or silage hay) which was used for growth and activity of soil microflora, initial soil pH (3.65; 4.2; and 5.1), and the ion content of irrigation solutions. The combination of limestone (2.0 g/ kg soil), silage addition (at rate of 45 g dry weight/ kg soil) in the beginning and reiterated at 6 month since the start of soil remediation, and periodical soil irrigation with slightly acidic solutions containing CaCl2 was sufficient the content of lead and arsenic in horizon A to be decreased to concentrations similar to the relevant MAC. The reducible, exchangeable, and carbonate mobile fractions were phases from which the pollutants was leached during the applied soil remediation. It determined the higher reduction of the pollutants bioavailability also as well as the process of ferric iron reduction was combined with neutralization of the soil acidity to pH (H2O) 6.2.

  11. The Carnoules mine. Generation of As-rich acid mine drainage, natural attenuation processes and solutions for passive in-situ remediation

    Elbaz-Poulichet, Françoise; Bruneel, Odile; Casiot, Corinne

    2006-01-01

    The former Carnoules Pb-Zn mine (Department of Gard, France) has produced 1.5 Mt of solid waste containing pyrite and associated metals and metalloids including arsenic and thallium. The tailings are stored behind a dam. Upon oxidation they generate acid (pH≤3) water containing up to 350mg/l of arsenic, 750 to 2700mg/L of iron, sulphate (2000-7500mg/L) and a few mg/L of heavy metals (Pb, Zn, Cd). The water surges at the bottom of the dam forming the Reigous Creek. For the last ten years, the ...

  12. Rare-earth-element fractionation patterns in estuarine sediments as a consequence of acid mine drainage: A case study in SW Spain

    Lopez-Gonzalez, N.; Borrego, J.; Carro, B.; Grande, J. A.; Torre, M. L. de la; Valente, T.

    2011-07-01

    Processes of seawater dilution and acid neutralization cause significant effects upon REE fractionation between the aqueous solution and sediments. This study describes the results of a recent investigation into such processes in the sediments of the Tinto and Odiel estuary. The results show differences in behaviour between light REEs (LREEs) and middle and heavy REEs (MREEs and HREEs). A relative depletion in La is observed as a consequence of the low pH values, which prevents the separation of LREEs from solution to the suspended matter. When acid neutralization occurs, on the other hand, an increase in the La content is related to the preferential separation of LREEs compared to MREEs and HREEs. Under these conditions three main fractionation patterns were distinguished: the first shows a slightly MREEenriched shape in sediments deposited in the fluvial zone; the second displays significant depletion in LREEs and a nearly flat tendency in MREEs and HREEs towards the estuarine mixing zone; and the third is enriched in total REEs and shows a relative increase in LREEs and MREEs. The evolution of these patterns reveals that pH is the key variable controlling REE fractionation in environments affected by acid mine drainage. (Author) 55 refs.

  13. Mobility of Po and U-isotopes under acid mine drainage conditions: an experimental approach with samples from Río Tinto area (SW Spain)

    Under acid mine drainage (AMD) conditions, the solubilities and mobilities of many elements are vastly different from conditions prevailing in most natural waters. Studies are underway in the Río Tinto area (Iberian Pyrite Belt), in order to understand the behavior and mobility of long-lived U-series radionuclides under AMD conditions. A set of leaching experiments utilizing typical country rocks from the Tinto River basin, waste rock pile composite materials, iron-rich riverbed sediments and gossan (weathered naturally rock) were performed towards this purpose. Initial leaching experiments using distilled water kept in contact with solid material for 300, 100, 50 and 1 h resulted in very low concentrations of U with 234U/238U activity ratios close to equilibrium and activity concentrations of 210Po < 0.03 mBq/g. Leaching experiments performed with sulfuric acid media (0.1 and 0.01 M), and contact times between the solid and solution for 24 h were conducted to quantify the amount of U-isotopes and 210Po leached, and the radioactive disequilibria generated between the radionuclides in the leachate. These experiments show that Po mobility in acidic conditions (pH around 1–2) is very low, with 210Po activity in the leachate to be 6% in average for the solid sample. By contrast, mobility of U-isotopes is higher than that of Po, around 1.2%

  14. Rare-earth-element fractionation patterns in estuarine sediments as a consequence of acid mine drainage: A case study in SW Spain

    Processes of seawater dilution and acid neutralization cause significant effects upon REE fractionation between the aqueous solution and sediments. This study describes the results of a recent investigation into such processes in the sediments of the Tinto and Odiel estuary. The results show differences in behaviour between light REEs (LREEs) and middle and heavy REEs (MREEs and HREEs). A relative depletion in La is observed as a consequence of the low pH values, which prevents the separation of LREEs from solution to the suspended matter. When acid neutralization occurs, on the other hand, an increase in the La content is related to the preferential separation of LREEs compared to MREEs and HREEs. Under these conditions three main fractionation patterns were distinguished: the first shows a slightly MREEenriched shape in sediments deposited in the fluvial zone; the second displays significant depletion in LREEs and a nearly flat tendency in MREEs and HREEs towards the estuarine mixing zone; and the third is enriched in total REEs and shows a relative increase in LREEs and MREEs. The evolution of these patterns reveals that pH is the key variable controlling REE fractionation in environments affected by acid mine drainage. (Author) 55 refs.

  15. Trace metal partitioning over a tidal cycle in an estuary affected by acid mine drainage (Tinto estuary, SW Spain)

    Hierro, A. [Department of Physics, Universitat Autònoma de Barcelona, 08193 Bellaterra (Spain); Department of Applied Physics, Facultad de Ciencias Experimentales, University of Huelva, Campus de El Carmen, Campus de Excelencia Internacional del Mar CEIMAR, 21071 Huelva (Spain); Olías, M., E-mail: manuel.olias@dgyp.uhu.es [Department of Geodynamics and Paleontology, Facultad de Ciencias Experimentales, University of Huelva, Campus de El Carmen, Campus de Excelencia Internacional del Mar CEIMAR, 21071 Huelva (Spain); Cánovas, C.R. [Department of Geodynamics and Paleontology, Facultad de Ciencias Experimentales, University of Huelva, Campus de El Carmen, Campus de Excelencia Internacional del Mar CEIMAR, 21071 Huelva (Spain); Martín, J.E.; Bolivar, J.P. [Department of Applied Physics, Facultad de Ciencias Experimentales, University of Huelva, Campus de El Carmen, Campus de Excelencia Internacional del Mar CEIMAR, 21071 Huelva (Spain)

    2014-11-01

    The Tinto River estuary is highly polluted with the acid lixiviates from old sulphide mines. In this work the behaviour of dissolved and particulate trace metals under strong chemical gradients during a tidal cycle is studied. The pH values range from 4.4 with low tide to 6.9 with high tide. Precipitation of Fe and Al is intense during rising tides and As and Pb are almost exclusively found in the particulate matter (PM). Sorption processes are very important in controlling the mobility (and hence bioavailability) of some metals and particularly affect Cu below pH 6. Above pH ∼ 6 Cu is desorbed, probably by the formation of Cu(I)–chloride complexes. Although less pronounced than Cu, also Zn desorption above pH 6.5 seems to occur. Mn and Co are affected by sorption processes at pH higher than ca. 6. Cd behaves conservatively and Ni is slightly affected by sorption processes. - Highlights: • The Tinto estuary shows strong pH gradients and high trace elements concentrations. • PM has a hysteretic relationship with tides and high contents of Fe, Al, As and Pb. • Co and Mn are controlled by river and sea water mixing and sorption processes. • Sorption processes strongly affect Cu below pH 6, above this value Cu is desorpted. • Cadmium behaves conservatively along the pH range studied (4.4–6.9)

  16. Neutralization/prevention of acid rock drainage using mixtures of alkaline by-products and sulfidic mine wastes.

    Alakangas, Lena; Andersson, Elin; Mueller, Seth

    2013-11-01

    Backfilling of open pit with sulfidic waste rock followed by inundation is a common method for reducing sulfide oxidation after mine closure. This approach can be complemented by mixing the waste rock with alkaline materials from pulp and steel mills to increase the system's neutralization potential. Leachates from 1 m3 tanks containing sulfide-rich (ca.30 wt %) waste rock formed under dry and water saturated conditions under laboratory conditions were characterized and compared to those formed from mixtures. The waste rock leachate produced an acidic leachate (pHhigh concentrations of As (65 mg/L), Cu (6 mg/L), and Zn (150 mg/L) after 258 days. The leachate from water-saturated waste rock had lower concentrations of As and Cu (9). The decrease of elemental concentration in the leachate was most pronounced for Pb and Zn, while Al and S were relatively high. Overall, the results obtained were promising and suggest that alkaline by-products could be useful additives for minimizing ARD formation. PMID:23740301

  17. Trace metal partitioning over a tidal cycle in an estuary affected by acid mine drainage (Tinto estuary, SW Spain)

    The Tinto River estuary is highly polluted with the acid lixiviates from old sulphide mines. In this work the behaviour of dissolved and particulate trace metals under strong chemical gradients during a tidal cycle is studied. The pH values range from 4.4 with low tide to 6.9 with high tide. Precipitation of Fe and Al is intense during rising tides and As and Pb are almost exclusively found in the particulate matter (PM). Sorption processes are very important in controlling the mobility (and hence bioavailability) of some metals and particularly affect Cu below pH 6. Above pH ∼ 6 Cu is desorbed, probably by the formation of Cu(I)–chloride complexes. Although less pronounced than Cu, also Zn desorption above pH 6.5 seems to occur. Mn and Co are affected by sorption processes at pH higher than ca. 6. Cd behaves conservatively and Ni is slightly affected by sorption processes. - Highlights: • The Tinto estuary shows strong pH gradients and high trace elements concentrations. • PM has a hysteretic relationship with tides and high contents of Fe, Al, As and Pb. • Co and Mn are controlled by river and sea water mixing and sorption processes. • Sorption processes strongly affect Cu below pH 6, above this value Cu is desorpted. • Cadmium behaves conservatively along the pH range studied (4.4–6.9)

  18. Downflow limestone beds for treatment of net-acidic, oxic, iron-laden drainage from a flooded anthracite mine, Pennsylvania, USA: 2. Laboratory evaluation

    Cravotta, C.A., III; Ward, S.J.; Hammarstrom, J.M.

    2008-01-01

    Acidic mine drainage (AMD) containing elevated concentrations of dissolved iron and other metals can be neutralized to varying degrees by reactions with limestone in passive treatment systems. We evaluated the chemical and mineralogical characteristics and the effectiveness of calcitic and dolomitic limestone for the neutralization of net-acidic, oxic, iron-laden AMD from a flooded anthracite mine. The calcitic limestone, with CaCO3 and MgCO3 contents of 99.8 and treatment system in 2003 at the Bell Mine, a large source of AMD and baseflow to the Schuylkill River in the Southern Anthracite Coalfield, in east-central Pennsylvania. In the winter of 2002-2003, laboratory neutralization-rate experiments evaluated the evolution of effluent quality during 2 weeks of continuous contact between AMD from the Bell Mine and the crushed calcitic or dolomitic limestone in closed, collapsible containers (cubitainers). The cubitainer tests showed that: (1) net-alkaline effluent could be achieved with detention times greater than 3 h, (2) effluent alkalinities and associated dissolution rates were equivalent for uncoated and Fe(OH)3-coated calcitic limestone, and (3) effluent alkalinities and associated dissolution rates for dolomitic limestone were about half those for calcitic limestone. The dissolution rate data for the cubitainer tests were used with data on the volume of effuent and surface area of limestone in the treatment system at the Bell Mine to evaluate the water-quality data for the first 1.5 years of operation of the treatment system. These rate models supported the interpretation of field results and indicated that treatment benefits were derived mainly from the dissolution of calcitic limestone, despite a greater quantity of dolomitic limestone within the treatment system. The dissolution-rate models were extrapolated on a decadal scale to indicate the expected decreases in the mass of limestone and associated alkalinities resulting from the long-term reaction of

  19. Modelling reactive transport of acid mine drainage in groundwater : Effect of geochemical processes spatially variable flow source location and distribution

    Tekelu Geberetsadike, Tegenne

    2004-01-01

    Impacts from mining waste deposits on groundwater resources have been recognized invarious parts of the world; though varied in scale depending on the composition of mineralsbeing mined, the level of technology employed and environmental commitment of thedevelopers. Mining activities usually involve milling, concentrating, and processing of oreswhich will result in a huge amount of waste, called tailings, usually deposited inimpoundments as a slurry, composed of fine grained geological materi...

  20. Use of Reactive Transport Modeling to Evaluate Remedial Options for an Acid Mine Drainage Stream, With Emphasis on Prediction Uncertainty

    Runkel, R. L.; Kimball, B. A.; Walton-Day, K.; Verplanck, P. L.

    2006-12-01

    Mineral Creek, a headwater stream in Southwestern Colorado, drains a sub-alpine watershed with numerous abandoned mines. A synoptic study conducted in 1999 indicates that the Mineral Creek watershed contributes 60% of the observed copper load for the Upper Animas River. In addition, zinc concentrations observed during the 1999 study exceed toxicity standards along the entire length of Mineral Creek. Given these findings, Mineral Creek is the potential site of future remedial actions to improve stream-water quality. Using the 1999 data, a reactive transport model was used to predict the effects of a small treatment system that neutralizes acidic inflow waters. Model application indicates that the treatment system would significantly improve water quality, producing higher pH values and lower dissolved metal concentrations downstream. Despite this progress, the results of model application may be of limited use for planning remediation, due to the potential uncertainty of model predictions (e.g. errors in the characterization of hydrologic and geochemical processes). An additional study was therefore conducted in 2005 to develop estimates of prediction uncertainty. The 2005 study implemented a paired-synoptic approach in which two synoptics were conducted under similar hydrologic conditions. The first synoptic was similar to the 1999 study in that the overall goal was to characterize stream-water quality under existing (acidic) conditions. The second synoptic study was conducted during a continuous sodium hydroxide injection that was designed to mimic a small treatment system. As in the initial model application, data collected under existing conditions (synoptic 1) will be used to calibrate the reactive transport model. Model inputs will then be modified to reflect the effects of treatment, and predictions of post-remediation water quality will be obtained by model application. The results of this application will then be compared to data from the post

  1. Flow and geochemical modeling of drainage from Tomitaka mine, Miyazaki, Japan.

    Yamaguchi, Kohei; Tomiyama, Shingo; Metugi, Hideya; Ii, Hiroyuki; Ueda, Akira

    2015-10-01

    The chemistry and flow of water in the abandoned Tomitaka mine of Miyazaki, western Japan were investigated. This mine is located in a non-ferrous metal deposit and acid mine drainage issues from it. The study was undertaken to estimate the quantities of mine drainage that needs to be treated in order to avoid acidification of local rivers, taking into account seasonal variations in rainfall. Numerical models aimed to reproduce observed water levels and fluxes and chemical variations of groundwater and mine drainage. Rock-water interactions that may explain the observed variations in water chemistry are proposed. The results show that: (1) rain water infiltrates into the deeper bedrock through a highly permeable zone formed largely by stopes that are partially filled with spoil from excavations (ore minerals and host rocks); (2) the water becomes acidic (pH from 3 to 4) as dissolved oxygen oxidizes pyrite; (3) along the flow path through the rocks, the redox potential of the water becomes reducing, such that pyrite becomes stable and pH of the mine drainage becomes neutral; and (4) upon leaving the mine, the drainage becomes acidic again due to oxidation of pyrite in the rocks. The present numerical model with considering of the geochemical characteristics can simulate the main variations in groundwater flow and water levels in and around the Tomitaka mine, and apply to the future treatment of the mine drainage. PMID:26456615

  2. Prediction of coal mine water flow due to the suspension of forced drainage - Gohan and Sabuk areas, Kangwon, Korea

    Kang, S.; Cho, W.

    2006-05-01

    Mine water can be pumped out in operating mines but, after mine closure, the suspension of forced drainage will eventually cause overflow and, more importantly, the acid mine drainage due to the rock-water interaction will harm workability at nearby mines and the groundwater quality. In Gohan and Sabuk areas, Kangwon, Korea, enormous coal production has been made at the hydrogeologically connected mines, from the same coal-bearing stratum. Recent closure of the Jungam(Oct. 2001) and the Dongwon(Nov. 2004) mines is suspected to cause serious environmental hazards with increased acid mine drainage and deterioration of the groundwater quality in nearby abandoned mines. The main objective of this study was to inquire the possibility of mine water overflow into the Dongwon mine due to the suspension of forced drainage, and subsequent water level uprise at the Samtan mine. The hydrological interconnectedness of adjacent mines and regional groundwater flow in this area were also investigated. It is found that the water level at the Samtan mine is steadily increasing due to obstruction of drainage by the subsidence of upper level drifts. Moreover, the subsidence has caused substantial increase in inflow rate through the fractured rockmass. Water level uprise can also be attributed to the decreased efficiency of the pumps, and to the scale built up inside of the drainage pipes. The Samtan and Dongwon mines are found to be connected at the 570 - 650 ML, and nearby mines including Kyungil, Jungdong, Taebaek, Hamtae, Donghae, and Eoryong mines are also interconnected. So, after the closure of the Sabuk mine, and also by the suspension of forced drainage at the Samtan mine, significant overflow will occur at Sabuk(-650ML), Samtan(-750ML), Hambaek(-710ML), Kyungil(-715ML) and Eoryong(-725ML) mines, all located below the 750ML of the Samtan mine. Results of this study can be applied for working out a countermeasure against unexpected overflow and acid mine drainage at abandoned

  3. Distribution and migration of heavy metals in soil and crops affected by acid mine drainage: Public health implications in Guangdong Province, China.

    Liao, Jianbo; Wen, Zewei; Ru, Xuan; Chen, Jundong; Wu, Haizhen; Wei, Chaohai

    2016-02-01

    Acid mine drainages (AMD) contain high concentrations of heavy metals, and their discharges into streams and rivers constitute serious environmental problems. This article examines the effects of AMD on soil, plant and human health at Dabaoshan mine in Guangdong Province, China. Although the large scale mining was stopped in 2011, the heavy metal pollution in soil continues to endanger crops and human health in that region. The objectives of this study were to elucidate distribution and migration of Cd, Cu, Zn, As and Pb and associated health implications to local inhabitants. We collected and analyzed 74 crop samples including 28 sugarcane, 30 vegetables, 16 paddy rice and the corresponding soil samples, used correlation and linear relationship for transformation process analysis, and applied carcinogenic and non-carcinogenic risk for hazard evaluation. Results showed that the local soils were heavily polluted with Cd, Cu and As (especially for Cd) and the mean Igeo value was as high as 3.77. Cadmium, Cu, and Zn in rice and vegetables were comparable with those found four years ago, while As and Pb in edible parts were 2 to 5 times lower than before. The root uptake of Cd and Zn contributed mainly to their high concentrations in crops due to high exchangeable fraction of soil, while leafy vegetables accumulated elevated As and Pb contents mainly due to the atmospheric deposition. Metal concentrations in sugarcane roots were higher than those in rice and vegetable roots. The risk assessment for crops consumption showed that the hazard quotients values were of 21 to 25 times higher than the threshold level for vegetables and rice, indicating a potential non-carcinogenic risk to the consumers. The estimated mean total cancer risk value of 0.0516 more than 100 times exceeded the USEPA accepted risk level of 1×10(-4), indicating unsuitability of the soil for cultivating the food crops. Therefore, the local agricultural and the land-use policies need to be reevaluated

  4. Community Genomic and Proteomic Analyses of Chemoautotrophic Iron-Oxidizing "Leptospirillum rubarum" (Group II) and "Leptospirillum ferrodiazotrophum" (Group III) Bacteria in Acid Mine Drainage Biofilms

    Goltsman, Daniela [University of California, Berkeley; Denef, Vincent [University of California, Berkeley; Singer, Steven [Lawrence Livermore National Laboratory (LLNL); Verberkmoes, Nathan C [ORNL; Lefsrud, Mark G [ORNL; Mueller, Ryan [University of California, Berkeley; Dick, Gregory J. [University of California, Berkeley; Sun, Christine [University of California, Berkeley; Wheeler, Korin [Lawrence Livermore National Laboratory (LLNL); Zelma, Adam [Lawrence Livermore National Laboratory (LLNL); Baker, Brett J. [University of California, Berkeley; Hauser, Loren John [ORNL; Land, Miriam L [ORNL; Shah, Manesh B [ORNL; Thelen, Michael P. [University of California, Berkeley; Hettich, Robert {Bob} L [ORNL; Banfield, Jillian F. [University of California, Berkeley

    2009-01-01

    We analyzed near-complete population (composite) genomic sequences for coexisting acidophilic iron-oxidizing Leptospirillum group II and III bacteria (phylum Nitrospirae) and an extrachromosomal plasmid from a Richmond Mine, Iron Mountain, CA, acid mine drainage biofilm. Community proteomic analysis of the genomically characterized sample and two other biofilms identified 64.6% and 44.9% of the predicted proteins of Leptospirillum groups II and III, respectively, and 20% of the predicted plasmid proteins. The bacteria share 92% 16S rRNA gene sequence identity and >60% of their genes, including integrated plasmid-like regions. The extrachromosomal plasmid carries conjugation genes with detectable sequence similarity to genes in the integrated conjugative plasmid, but only those on the extrachromosomal element were identified by proteomics. Both bacterial groups have genes for community-essential functions, including carbon fixation and biosynthesis of vitamins, fatty acids, and biopolymers (including cellulose); proteomic analyses reveal these activities. Both Leptospirillum types have multiple pathways for osmotic protection. Although both are motile, signal transduction and methyl-accepting chemotaxis proteins are more abundant in Leptospirillum group III, consistent with its distribution in gradients within biofilms. Interestingly, Leptospirillum group II uses a methyl-dependent and Leptospirillum group III a methyl-independent response pathway. Although only Leptospirillum group III can fix nitrogen, these proteins were not identified by proteomics. The abundances of core proteins are similar in all communities, but the abundance levels of unique and shared proteins of unknown function vary. Some proteins unique to one organism were highly expressed and may be key to the functional and ecological differentiation of Leptospirillum groups II and III.

  5. Community genomic and proteomic analysis of chemoautotrophic, iron-oxidizing "Leptospirillum rubarum" (Group II) and Leptospirillum ferrodiazotrophum (Group III) in acid mine drainage biofilms

    Goltsman, Daniela [University of California, Berkeley; Denef, Vincent [University of California, Berkeley; Singer, Steven [Lawrence Livermore National Laboratory (LLNL); Verberkmoes, Nathan C [ORNL; Lefsrud, Mark G [McGill University, Montreal, Quebec; Mueller, Ryan [University of California, Berkeley; Dick, Gregory J. [University of California, Berkeley; Sun, Christine [University of California, Berkeley; Wheeler, Korin [Lawrence Livermore National Laboratory (LLNL); Zelma, Adam [Lawrence Livermore National Laboratory (LLNL); Baker, Brett J. [University of California, Berkeley; Hauser, Loren John [ORNL; Land, Miriam L [ORNL; Shah, Manesh B [ORNL; Thelen, Michael P. [University of California, Berkeley; Hettich, Robert {Bob} L [ORNL; Banfield, Jillian F. [University of California, Berkeley

    2009-01-01

    We analyzed near-complete population (composite) genomic sequences for coexisting acidophilic iron-oxidizing Leptospirillum Groups II and III bacteria (phylum Nitrospirae) and an extrachromosomal plasmid from a Richmond Mine, CA acid mine drainage (AMD) biofilm. Community proteomic analysis of the genomically characterized sample and two other biofilms identified 64.6% and 44.9% of the predicted proteins of Leptospirillum Groups II and III, respectively and 20% of the predicted plasmid proteins. The bacteria share 92% 16S rRNA gene sequence identity and > 60% of their genes, including integrated plasmid-like regions. The extrachromosomal plasmid encodes conjugation genes with detectable sequence similarity to genes in the integrated conjugative plasmid, but only those on the extrachromosomal element were identified by proteomics. Both bacteria have genes for community-essential functions, including carbon fixation, biosynthesis of vitamins, fatty acids and biopolymers (including cellulose); proteomic analyses reveal these activities. Both Leptospirillum types have multiple pathways for osmotic protection. Although both are motile, signal transduction and methyl-accepting chemotaxis proteins are more abundant in Leptospirillum Group III, consistent with its distribution in gradients within biofilms. Interestingly, Leptospirillum Group II uses a methyl-dependent and Leptospirillum Group III a methyl-independent response pathway. Although only Leptospirillum Group III can fix nitrogen, these proteins were not identified by proteomics. Abundances of core proteins are similar in all communities, but abundance levels of unique and shared proteins of unknown function vary. Some proteins unique to one organism were highly expressed and may be key to the functional and ecological differentiation of Leptospirillum Groups II and III.

  6. Recycling Facilities - Mine Drainage Treatment/Land Recycling Project Locations

    NSGIC GIS Inventory (aka Ramona) — Mine Drainage Treatment/Land Reclamation Locations are clean-up projects that are working to eliminate some form of abandoned mine. The following sub-facility types...

  7. Downflow limestone beds for treatment of net-acidic, oxic, iron-laden drainage from a flooded Anthracite Mine, Pennsylvania, USA: 1. Field evaluation

    Cravotta, C.A., III; Ward, S.J.

    2008-01-01

    Passive-treatment systems that route acidic mine drainage (AMD) through crushed limestone and/or organic-rich substrates have been used to remove the acidity and metals from various AMD sources, with a wide range of effects. This study evaluates treatment of net-acidic, oxic, iron-laden AMD with limestone alone, and with organic-rich compost layered with the limestone. In the fall of 2003, a treatment system consisting of two parallel, 500-m2 downflow cells followed by a 400-m2 aerobic settling pond and wetland was installed to neutralize the AMD from the Bell Mine, a large source of AMD and baseflow to the Schuylkill River in the Southern Anthracite Coalfield, in east-central Pennsylvania. Each downflow cell consisted of a lower substrate layer of 1,090 metric tons (t) of dolomitic limestone (60 wt% CaCO3) and an upper layer of 300 t of calcitic limestone (95 wt% CaCO3); one of the downflow cells also included a 0.3 m thick layer of mushroom compost over the limestone. AMD with pH of 3.5-4.3, dissolved oxygen of 6.6-9.9 mg/L, iron of 1.9-5.4 mg/L, and aluminum of 0.8-1.9 mg/L flooded each cell to a depth 0.65 m above the treatment substrates, percolated through the substrates to underlying, perforated outflow pipes, and then flowed through the aerobic pond and wetland before discharging to the Schuylkill River. Data on the flow rates and chemistry of the effluent for the treatment system indicated substantial neutralization by the calcitic limestone but only marginal effects from the dolomitic limestone or compost. Because of its higher transmissivity, the treatment cell containing only limestone neutralized greater quantities of acidity than the cell containing compost and limestone. On average, the treatment system removed 62% of the influent acidity, 47% of the dissolved iron, 34% of the dissolved aluminum, and 8% of the dissolved manganese. Prior to treatment of the Bell Discharge, the Schuylkill River immediately below its confluence with the discharge had p

  8. Characterization and activity studies of highly heavy metal resistant sulphate-reducing bacteria to be used in acid mine drainage decontamination.

    Martins, Mónica; Faleiro, M Leonor; Barros, Raúl J; Veríssimo, A Raquel; Barreiros, M Alexandra; Costa, M Clara

    2009-07-30

    Biological treatment with sulphate-reducing bacteria (SRB) has been considered as the most promising alternative for acid mine drainage (AMD) decontamination. Normally, these wastewaters contain high concentrations of sulphate and heavy metals, so the search for SRB highly resistant to metals is extremely important for the development of a bioremediation technology. A SRB consortium resistant to high concentrations of heavy metals (Fe, Cu and Zn), similar to those typically present in AMD, was obtained among several environmental samples, from a wastewater treatment plant. The phylogenetic analysis of the dsr gene sequence revealed that this consortium contains species of SRB affiliated to Desulfovibrio desulfuricans and Desulfobulbus rhabdoformis. The results show that the presence of usually lethal concentrations of Fe (400mg/L), Zn (150 mg/L) and Cu (80 mg/L) is not toxic for the sulphate-reducing bacteria present in this sample. As a consequence, a very good efficiency in terms of sulphate reduction and metals removal was obtained. Both ethanol and lactate can be used by this inoculum as carbon source. With the other samples tested sulphate reduction was inhibited by the presence of copper and zinc. This highly metal resistant consortium will be used to inoculate a bioreactor to carry out AMD decontamination. PMID:19135795

  9. Arsenic Scavenging by Al-Substituted Ferrihydrites in a Circumneutral pH River Impacted by the Acid Mine Drainage of Carnoulès, Gard, France

    ADRA, A.; Morin, G.; ona-Nguema, G.; Maillot, F.; Casiot, C.; Bruneel, O.

    2013-12-01

    Ferrihydrite (Fh) is a nanocrystalline ferric oxyhydroxide involved in the retention of pollutants in natural systems and in water-treatment processes. The status and properties of major chemical impurities in natural Fh is however still scarcely documented. Here we investigated the structure and reactivity of aluminum-rich Fh from river-bed sediments collected in a circumneutral river (pH 6-7) impacted by an arsenic-rich acid mine drainage (AMD). Extended X-ray absorption fine structure (EXAFS) spectroscopy at the Fe K-edge shows that Fh is the predominant mineral phase forming after neutralization of the AMD, in association with minor amount of schwertmannite transported from the AMD. EXAFS analysis indicates that Al(III) substitutes for Fe(III) ions into the Fh structure in the natural sediment samples, with local aluminum concentration within the 20-37×7 mol%Al range, in agreement with bulk chemical compositions. Synthetic aluminous Fh analogues prepared in the present study are found to be less Al-substituted (14-18×4 mol%Al). Finally, EXAFS analysis at the arsenic K-edge indicates that As(V) form similar inner-sphere surface complexes on the natural and synthetic Al-substituted Fh studied. Our results provide direct evidences for the scavenging of arsenic by natural Al- Fh, with possible implications for other pollutants in natural or engineered systems.

  10. Regeneration of barium carbonate from barium sulphide in a pilot-scale bubbling column reactor and utilization for acid mine drainage.

    Mulopo, J; Zvimba, J N; Swanepoel, H; Bologo, L T; Maree, J

    2012-01-01

    Batch regeneration of barium carbonate (BaCO(3)) from barium sulphide (BaS) slurries by passing CO(2) gas into a pilot-scale bubbling column reactor under ambient conditions was used to assess the technical feasibility of BaCO(3) recovery in the Alkali Barium Calcium (ABC) desalination process and its use for sulphate removal from high sulphate Acid Mine Drainage (AMD). The effect of key process parameters, such as BaS slurry concentration and CO(2) flow rate on the carbonation, as well as the extent of sulphate removal from AMD using the recovered BaCO(3) were investigated. It was observed that the carbonation reaction rate for BaCO(3) regeneration in a bubbling column reactor significantly increased with increase in carbon dioxide (CO(2)) flow rate whereas the BaS slurry content within the range 5-10% slurry content did not significantly affect the carbonation rate. The CO(2) flow rate also had an impact on the BaCO(3) morphology. The BaCO(3) recovered from the pilot-scale bubbling column reactor demonstrated effective sulphate removal ability during AMD treatment compared with commercial BaCO(3). PMID:22233912

  11. Determination and evaluation of hexavalent chromium in power plant coal combustion by-products and cost-effective environmental remediation solutions using acid mine drainage.

    Kingston, H M Skip; Cain, Randy; Huo, Dengwei; Rahman, G M Mizanur

    2005-09-01

    The chromium species leaching from a coal combustion fly ash landfill has been characterized as well as a novel approach to treat leachates rich in hexavalent chromium, Cr(VI), by using another natural waste by-product, acid mine drainage (AMD), has been investigated during this study. It is observed that as much as 8% (approximately 10 microg g(-1) in fly ash) of total chromium is converted to the Cr(VI) species during oxidative combustion of coal and remains in the resulting ash as a stable species, however, it is significantly mobile in water based leaching. Approximately 1.23 +/- 0.01 microg g(-1) of Cr(VI) was found in the landfill leachate from permanent deposits of aged fly ash. This study also confirmed the use of AMD, which often is in close proximity to coal combustion by-product landfills, is an extremely effective and economical remediation option for the elimination of hexavalent chromium in fly ash generated leachate. Speciated isotope dilution mass spectrometry (SIDMS), as described in EPA Method 6800, was used to analytically evaluate and validate the field application of the ferrous iron and chromate chemistry in the remediation of Cr(VI) runoff. PMID:16121270

  12. Biochemical passive reactors for treatment of acid mine drainage: Effect of hydraulic retention time on changes in efficiency, composition of reactive mixture, and microbial activity.

    Vasquez, Yaneth; Escobar, Maria C; Neculita, Carmen M; Arbeli, Ziv; Roldan, Fabio

    2016-06-01

    Biochemical passive treatment represents a promising option for the remediation of acid mine drainage. This study determined the effect of three hydraulic retention times (1, 2, and 4 days) on changes in system efficiency, reactive mixture, and microbial activity in bioreactors under upward flow conditions. Bioreactors were sacrificed in the weeks 8, 17 and 36, and the reactive mixture was sampled at the bottom, middle, and top layers. Physicochemical analyses were performed on reactive mixture post-treatment and correlated with sulfate-reducing bacteria and cellulolytic and dehydrogenase activity. All hydraulic retention times were efficient at increasing pH and alkalinity and removing sulfate (>60%) and metals (85-99% for Fe(2+) and 70-100% for Zn(2+)), except for Mn(2+). The longest hydraulic retention time (4 days) increased residual sulfides, deteriorated the quality of treated effluent and negatively impacted sulfate-reducing bacteria. Shortest hydraulic retention time (1 day) washed out biomass and increased input of dissolved oxygen in the reactors, leading to higher redox potential and decreasing metal removal efficiency. Concentrations of iron, zinc and metal sulfides were high in the bottom layer, especially with 2 day of hydraulic retention time. Sulfate-reducing bacteria, cellulolytic and dehydrogenase activity were higher in the middle layer at 4 days of hydraulic retention time. Hydraulic retention time had a strong influence on overall performance of passive reactors. PMID:27016821

  13. Using fluorescence-based microplate assay to assess DOM-metal binding in reactive materials for treatment of acid mine drainage

    Carmen Mihaela Neculita; Yves Dudal; Gerald J Zagury

    2011-01-01

    One potential drawback of compost-based passive bioreactors, which is a promising biotechnology for acid mine drainage (AMD) treatment, is the transport of dissolved organic matter (DOM)-metal complexes in surface waters.To address this problem, the objective of this study was to assess the maximum capacity of organic substrates to release soluble DOM-metal complexes in treated water.The reactivities of DOM in maple wood chips and sawdust, composted poultry manure, and leaf compost were quantified toward Cd2+, Ni2+, Fe2+, and Cu2+ using fluorescence quenching.The DOM showed the highest reactivity toward Fe, but a limited number of available sites for sorption, whereas DOM-Cd complexes exhibited the lowest fluorescence quenching.Overall, the DOM from a mixture of wastes formed higher concentrations of DOM-metal complexes relative to sole substrates.Among DOM-metal complexes, the concentrations of DOM-Ni complexes were the highest.After reaching steady-state, low concentrations of DOM-metal complexes were released in treated water, which is in agreement with theoretical predictions based on geochemical modeling.Therefore, in addition to physicochemical characterization, fluorescence quenching technique is recommended for the substrate selection of bioreactors.

  14. Seventh symposium on coal mine drainage research. NCA/BCR coal conference and Expo IV

    None

    1977-01-01

    The Seventh Symposium on Coal Mine Drainage Research, sponsored by the National Coal Association and Bituminous Coal Research, Inc., was held at the Kentucky Fair and Exposition Center, Louisville, Kentucky, October 18-20, 1977. Seventeen papers from the proceedings have been entered individually into EDB and ERA. Topics covered include chemical reactions of pyrite oxidation and acid formation in spoil banks, abandoned mines, etc., formation of small acid lakes from the drainage and their neutralization by natural and other neutralization measures, trace elements in acid mine drainage, ground water contamination, limnology, effects of surface mined ground reclamation and neutralization, water purification and treatment, mining and coal preparation plant waste disposal, ash and fly ash disposal (to minimize leaching from the wastes), runoff from large coal storage stockpiles during storms (prevention of environmental effects by collection and neutralization by passing through an ash pond). (LTN)

  15. Jarosite versus Soluble Iron-Sulfate Formation and Their Role in Acid Mine Drainage Formation at the Pan de Azúcar Mine Tailings (Zn-Pb-Ag, NW Argentina

    Jesica Murray

    2014-05-01

    Full Text Available Secondary jarosite and water-soluble iron-sulfate minerals control the composition of acid mine waters formed by the oxidation of sulfide in tailings impoundments at the (Zn-Pb-Ag Pan de Azúcar mine located in the Pozuelos Lagoon Basin (semi-arid climate in Northwest (NW Argentina. In the primary zone of the tailings (9.5 wt % pyrite-marcasite precipitation of anglesite (PbSO4, wupatkite ((Co,Mg,NiAl2(SO44 and gypsum retain Pb, Co and Ca, while mainly Fe2+, Zn2+, Al3+, Mg2+, As3+/5+ and Cd2+ migrate downwards, forming a sulfate and metal-rich plume. In the oxidation zone, jarosite (MFe3(TO42(OH6 is the main secondary Fe3+ phase; its most suitable composition is M = K+, Na+, and Pb2+and TO4 = SO42−; AsO42−. During the dry season, iron-sulfate salts precipitate by capillary transport on the tailings and at the foot of DC2 (tailings impoundment DC2 tailings dam where an acid, Fe2+ rich plume outcrops. The most abundant compounds in the acid mine drainage (AMD are SO42−, Fe2+, Fe3+, Zn2+, Al3+, Mg2+, Cu2+, As3+/5+, Cd2+. These show peak concentrations at the beginning of the wet season, when the soluble salts and jarosite dissolve. The formation of soluble sulfate salts during the dry season and dilution during the wet season conform an annual cycle of rapid metals and acidity transference from the tailings to the downstream environment.

  16. Remediação de drenagem ácida de mina usando zeólitas sintetizadas a partir de cinzas leves de carvão Remediation of acid mine drainage using zeolites synthesized from coal fly ash

    Denise Alves Fungaro; Juliana de Carvalho Izidoro

    2006-01-01

    Zeolitic material was synthesized from coal fly ashes (baghouse filter fly ash and cyclone filter fly ash) by hydrothermal alkaline activation. The potential application of the zeolitic product for decontamination of waters from acid mine drainage was evaluated. The results showed that a dose of 30 g L-1 of zeolitic material allowed the water to reach acceptable quality levels after treatment. Both precipitation and cation-exchange processes accounted for the reduction in the pollutant concen...

  17. Hydrological and geochemical control of metals and arsenic in a Mediterranean river contaminated by acid mine drainage (the Amous River, France) ; preliminary assessment of impacts on fish (Leuciscus cephalus)

    Casiot, C.; Egal, M; Elbaz-Poulichet, F.; Bruneel, Odile; Bancon-Montigny, C.; Cordier, M. A.; Gomez, E.; Aliaume, C.

    2009-01-01

    Dissolved and particulate concentrations of metals (Fe, Al, Mn, Co, Ni, Cu, Zn, Cd, Tl, Pb) and As were monitored over a 5 year period in the Amous River downstream of its confluence with a creek severely affected by acid mine drainage (AMD) originating from a former Pb-Zn mine. Water pH ranged from 6.5 to 8.8. Metals were predominantly in dissolved form, except Fe and Pb, which were in particulate form. In the particulate phase, metals were generally associated with Al oxides, whereas As was...

  18. Mineralogy and geochemistry of trace metals and REE in volcanic massive sulfide host rocks, stream sediments, stream waters and acid mine drainage from the Lousal mine area (Iberian Pyrite Belt, Portugal)

    Acid mine drainage represents a major source of water pollution in the Lousal area. The concentrations of trace metals and the rare earth elements (REE) in the host rocks, stream sediment, surface waters and acid mine drainage (AMD) associated with abandoned mine adits and tailings impoundments were determined, in order to fingerprint their sources and to understand their mobility and water-rock interaction. The results show that the Fe-SO4-rich acid waters vary substantially in composition both spatially and seasonally. These waters include very low pH (mostly in the range 1.9-3.0), extreme SO4 concentrations (4635-20,070 mg L-1SO42-), high metal contents (Fe, Al, Cu, Zn and Mn) and very high REE contents. The trace metal concentrations decrease downstream from the discharge points either due to precipitation of neoformed phases or to dilution. The North-American shale composite (NASC)-normalized patterns corresponding to sediment from one stream (Corona stream) show a flat tendency or are slightly enriched in light-REE (LREE). The NASC-normalized patterns corresponding to acidic mine waters show enrichment in the middle REE (MREE) with respect to the LREE and heavy REE (HREE). Moreover, the REE concentrations in acidic mine waters are 2 or 3 orders of magnitude higher than those of the surface waters. Changes of REE concentrations and variation of Eu anomaly show two spatially distinct patterns: (a) pond and spring waters with higher REE concentrations (ranging from 375 to 2870 μg L-1), that records conspicuous negative Eu anomaly, and (b) seeps from tailings impoundments corresponding to lower REE concentrations than the first pattern (ranging from 350 to 1139 μg L-1) with typically negative Eu anomaly. The stream water samples collected from the impacted stream during the spring show a low pH (2.8-3.1) and contain high concentrations of Fe and trace elements (up to 61 mg L-1). Also, temporal variations of the REE concentrations were observed in the Corona

  19. Mapping of the Frazee Mine, the Western Maryland Coal Combustion By-Products/Acid Mine Drainage Initiative, Part 2 of 3

    Maryland coal production over the years before 1977 reveals that Maryland coal basins have void space from mining a quarter billion tons of coal. The exposure of sulfur-bearing minerals in these mine voids to oxygen and water generates AMD, which is toxic to aquatic flora and fauna. It is estimated that about 450 miles of waterways in western Maryland are impacted by AMD. The majority of these waterways ultimately drain to the east, and affect the overall water quality of the Chesapeake Bay. Typically, AMD is treated by dosing discharges with limestone, which only provides a temporary solution as AMD continues to form at its source in underground mines. The Maryland Department of Natural Resources (DNR) Power Plant Research Program (PPRP) and the Maryland Department of the Environment Bureau of Mines (MDE) have undertaken the Western Maryland CCB/AMD Initiative (the Initiative), which is a joint effort with private industry to develop permanent solutions to abate AMD at its source. The Initiative's goal is to demonstrate the beneficial application of alkaline CCBs to abate AMD from underground coal mines. The Initiative is based on the concept that alkaline CCBs generated by clean coal technologies, such as fluidized bed combustion (FBC) and flue gas desulfurization (FGD), can be injected into underground mines to prevent the formation of AMD by sealing mines from exposure to oxygen and water. This goal will be met by performing the following: Determining optimum grout formulations for mine injection; Optimizing engineering techniques for mine reclamation to achieve economic viability; Implementing appropriately-sized demonstration projects, progressing to full-scale applications at Maryland's largest abandoned mines; and Developing industry partnerships for implementation of the Initiative's findings to abate AMD in western Maryland

  20. Assessment, water-quality trends, and options for remediation of acidic drainage from abandoned coal mines near Huntsville, Missouri, 2003-2004

    Christensen, Eric D.

    2005-01-01

    Water from abandoned underground coal mines acidifies receiving streams in the Sugar Creek Basin and Mitchell Mine Basin near Huntsville, Missouri. A 4.35-kilometer (2.7-mile) reach of Sugar Creek has been classified as impaired based on Missouri's Water Quality Standards because of small pH values [water quality in Sugar Creek. Metal and sulfate loads increased and pH decreased immediately downstream from Sugar Creek's confluence with the Calfee Slope and Huntsville Gob drainages that discharge AMD into Sugar Creek. Similar effects were observed in the Mitchell Mine drainage that receives AMD from a large mine spring. Comparisons of water-quality samples from this study and two previous studies by the U.S. Geological Survey in 1987-1988 and the Missouri Department of Natural Resources in 2000-2002 indicate that AMD generation in the Sugar Creek Basin and Mitchell Mine Basin is declining, but the data are insufficient to quantify any trends or time frame. AMD samples from the largest mine spring in the Calfee Slope subbasin indicated a modest but significant increase in median pH from 4.8 to 5.2 using the Wilcoxan rank-sum test (p water or sewage effluent can further increase pH as indicated by geochemical modeling, but will not totally achieve water-quality goals because of limited discharges. A combination of treatments including settling ponds, oxic or anoxic limestone drains, and possibly successive alkalinity producing systems to remediate AMD will likely be required in the Sugar Creek Basin and Mitchell Mine Basin to consistently meet Missouri's Water Quality Standards.

  1. Technology of gas drainage and utilization in Huaibei mining area

    LI Wei; XU Rui

    2009-01-01

    With the characteristics of coal seam geology and gas occurrence, a "ground-underground" integrated gas drainage method was formed, which can relieve gas pressure and increase permeability by mining the protection seams in conditional regions. After coal seam gas drainage, high gas outburst seam was converted to low gas safety seam. In the coal face mining process, safety and high efficient coal mining were realized by the measure of gas-suction over mining. In addition to the drainage gas for civil gas and gas power generation, the Huaibei Mining Group has actively carried out research on the utilization technology of methane drainage by ventilation. On the one hand, it can save precious energy; on the other hand, it can protect the environment for people's survival. In 2007, the amount of coal mine gas drainage was 120 hm3; the rate of coal mine gas drainage was 44%. Compared with the year 2002, the amount of coal mine gas drainage increased by two times. Meanwhile, the utilization rate of gas increased rapidly.

  2. Proceedings of the international land reclamation and mine drainage conference and third international conference on the abatement of acidic drainage. Volume 4: Abandoned mine lands and topical issues -- SP 06D-94

    Volume 4 of these proceedings is divided into the following sections: Subsidence--Reclamation, characterization (6 papers); Subsidence--Structural response (7); Abandoned mine land studies (6); Mine Hydrology--Topical issues (4); Mine waste--Topical issues (6); Policy issues (6); Miscellaneous poster session (14); and Abstracts (17). 53 papers dealing with or applicable to coal mining have been processed separately for inclusion on the data base

  3. THE EXTENT OF MINE DRAINAGE INTO STREAMS OF THE CENTRAL APPALACHIAN AND ROCKY MOUNTAIN REGIONS

    Runoff and drainage from active and inactive mines are contaminating streams throughout the United States with acidic and metal contaminated waters and sediments. The extent of mining impacts on streams of the coal bearing region of the Central Appalachians and the metal bearing...

  4. Ecological response of benthic foraminifera to the acid drainage from mine areas. An example from the Gromolo torrent mouth (Eastern Ligurian Sea, Italy)

    Bergamin, Luisa; Capello, Marco; Carbone, Cristina; Magno, Maria Celia; Consani, Sirio; Cutroneo, Laura; Ferraro, Luciana; Pierfranceschi, Giancarlo; Romano, Elena

    2016-04-01

    Benthic foraminiferal assemblages react in short time to natural and anthropogenic environmental changes and, for this, they are considered as reliable indicators of environmental quality. An interesting application of these indicators is the study of their response to environmental changes in coastal marine areas, affected by dismissed mines and dump areas. The Libiola Fe-Cu sulphide mine was intensively exploited in 19th and 20th centuries, and the activity ended in 1962. The sulphide mineral assemblages consist of pyrite and chalcopyrite, with minor sphalerite and pyrrhotite, in a gangue of quartz and chlorite. The sulphide ore occurs within the Jurassic ophiolites of the Northern Apennines which were subjected to metamorphic and tectonic processes during the subsequent Apennine orogenesis. Waters circulating in the Libiola mine area, and discharging in the adjacent streams and creeks, are strongly polluted due to the diffuse occurrence of Acid Mine Drainage processes. The Gromolo torrent collects these acidic waters enriched of heavy metals which flow into Ligurian Sea. The study area is characterised by a shelf with a gentle slope, mainly constituted by sediment supplied by Entella torrent. The general circulation has trend from East to West and the coastal drift is generally eastwards. A total of 15 marine sediment samples (upper 2 cm) were collected by means of Van Veen grab in the coastal zone close to the Gromolo mouth and analyzed for living (rose Bengal stained) and dead benthic foraminifera, together with grain size, metals and trace elements, and metal fractioning. Quantitative foraminiferal parameters, like as abundance, species diversity, heterogeneity and assemblage composition, were determined and evaluated for environmental purpose. Additionally, possible increase above the natural background level of deformed specimens was considered as indicative of metal contamination. The grain-size analyses highlighted mainly sandy sediments, characterized by

  5. Recognition of a Biofilm at the Sediment-Water Interface of AN Acid Mine Drainage-Contaminated Stream, and its Role in Controlling Iron Flux

    Boult, Stephen; Johnson, Nicholas; Curtis, Charles

    1997-03-01

    Material collected over a month on plates attached to the bed of the Afon Goch, Anglesey, a stream highly contaminated by acid mine drainage (AMD), was either examined intact by electron microscopy or suspended and cultured to reveal the presence of microbiota. Certain of the aerobic microbiota were identified, the genus Pseudomonas formed the commonest isolate and cultures of Serratia plymuthica were grown in order to compare the biofilms formed with the material collected in the Afon Goch. The material at the sediment-water interface of the Afon Goch was of similar underlying morphology to that of the cultured biofilms. However, the former had a superficial granular coating of equidimensional (60-100 nm) and evenly spaced iron rich particles (determined by X-ray microanalysis). The sediment-water interface of this AMD-contaminated stream is therefore best described as a highly contaminated biofilm. Evidence from previous work suggests that the streambed is active in iron removal from the water column. The intimate association of iron with microbiota at the streambed, therefore, implies that iron flux prediction may not be possible from physical and chemical data alone but requires knowledge of biofilm physiology and ecology.Microbially mediated metal precipitation, both by single bacteria and by biofilms, has been reported elsewhere but mass balance considerations suggest that this explanation cannot hold good for the large amounts of iron hydroxide depositing from waters of the prevalent pH and redox status. Filtered stream water analyses indicate the presence of colloidal iron hydroxide and also its removal downstream where ochreous (iron hydroxide rich) material accumulates. The process of iron immobilization is likely to be the attraction and physical trapping of colloidal iron hydroxide by extracellular polymeric substances (EPS) which constitute the matrix of biofilms.

  6. The geochemistry of acid rock drainage and estimating its ecological impact at a uranium mine in tropical Australia

    Geochemical kinetic modelling of the effluent chemistry from waste rock dumps at the Rum Jungle copper/uranium mine has been undertaken. The modelling examined the periods both before and after the installation of covers being placed on the dumps. Effluent from the waste rock dump migrates into the adjacent East Branch of the Finniss River and may induce ecological detriment. The model predicts pollutant loads that are significantly greater than that currently observed in the field. The observed reduction of pollutant loads after the cover was placed on the dump is attributed to a decrease in the rate of water infiltration due to the cover placement. It is estimated that a significant increase in pollutant loads is likely to occur Ca. 35 years after remediation. A computer program for ecological risk assessment, AQUARISK, has been developed and applied to evaluate the likelihood of biotic detriment due to exposure to pollutants from the site. Measured and modelled water quality data have been used in AQUARISK, in conjunction with national water quality guidelines and literature derived ecotoxicological data, to estimate the ecological risk for copper, this being a key pollutant. Both the present and past copper concentrations in the East Branch have a 100% risk of exceeding current regulatory criteria in addition to criteria derived from available dose-response data. The predicted increase in copper is unlikely to change these risks. However, the present reduction has led to an appreciable increase in the measured diversity of species at the site (from 8 to 50% implied) as also reflected in the AQUARISK estimate of increased tolerance (from 5 to 36% predicted). Modelled bioavailable copper concentrations will have a deleterious impact on the present degree of recovery and a return to the previous, unacceptably low, system diversity. To achieve a situation where 67% of species are likely to tolerate the effluent from the site, the average target copper concentration

  7. Seasonal water quality variations in a river affected by acid mine drainage: the Odiel River (South West Spain)

    This paper intends to analyse seasonal variations of the quality of the water of the Odiel River. This river, together with the Tinto River, drains the Iberian Pyrite Belt (IPB), a region containing an abundance of massive sulphide deposits. Because of mining activity dating back to prehistoric times, these two rivers are heavily contaminated. The Odiel and Tinto Rivers drain into a shared estuary known as the Ria of Huelva. This work studies dissolved contaminant data in water of the Odiel River collected by various organisations, between October 1980 and October 2002, close to the rivers entry into the estuary. Flow data for this location were also obtained. The most abundant metals in the water, in order of abundance, are zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu). Arsenic (As), cadmium (Cd) and lead (Pb) are also present but in much lower quantities. The quality of the river water is linked to precipitation; the maximum sulphate, Fe, Zn, Mn, Cd and Pb concentrations occur during the autumn rains, which dissolve the Fe hydroxysulphates that were precipitated during the summer months. In winter, the intense rains cause an increase in the river flow, producing a dilution of the contaminants and a slight increase in the pH. During spring and summer, the sulphate and metal concentration (except Fe) recover and once again increase. The Fe concentration pattern displays a low value during summer due to increased precipitation of ferric oxyhydroxides. The arsenic concentration displays a different evolution, with maximum values in winter, and minimum in spring and summer as they are strongly adsorbed and/or coprecipitated by the ferric oxyhydroxides. Mn and sulphates are the most conservative species in the water. Relative to sulphate, Mn, Zn and Cd, copper displays greater values in winter and lower ones in summer, probably due to its coprecipitation with hydroxysulphates during the spring and summer months. Cd and Zn also appear to be affected by the same

  8. Deciphering the role of Paenibacillus strain Q8 in the organic matter recycling in the acid mine drainage of Carnoulès

    Delavat François

    2012-02-01

    Full Text Available Abstract Background The recycling of the organic matter is a crucial function in any environment, especially in oligotrophic environments such as Acid Mine Drainages (AMDs. Polymer-degrading bacteria might play an important role in such ecosystem, at least by releasing by-products useful for the rest of the community. In this study, physiological, molecular and biochemical experiments were performed to decipher the role of a Paenibacillus strain isolated from the sediment of Carnoulès AMD. Results Even though Paenibacillus sp. strain Q8 was isolated from an oligotrophic AMD showing an acidic pH, it developed under both acidic and alkaline conditions and showed a heterotrophic metabolism based on the utilization of a broad range of organic compounds. It resisted to numerous metallic stresses, particularly high arsenite (As(III concentrations (> 1,800 mg/L. Q8 was also able to efficiently degrade polymers such as cellulose, xylan and starch. Function-based screening of a Q8 DNA-library allowed the detection of 15 clones with starch-degrading activity and 3 clones with xylan-degrading activity. One clone positive for starch degradation carried a single gene encoding a "protein of unknown function". Amylolytic and xylanolytic activities were measured both in growing cells and with acellular extracts of Q8. The results showed the ability of Q8 to degrade both polymers under a broad pH range and high As(III and As(V concentrations. Activity measurements allowed to point out the constitutive expression of the amylase genes and the mainly inducible expression of the xylanase genes. PACE demonstrated the endo-acting activity of the amylases and the exo-acting activity of the xylanases. Conclusions AMDs have been studied for years especially with regard to interactions between bacteria and the inorganic compartment hosting them. To date, no study reported the role of microorganisms in the recycling of the organic matter. The present work suggests that

  9. Laboratory and field evaluation of municipal compost/limestone/iron mixtures as filling material for permeable reactive barriers for in-situ acid mine drainage treatment

    Gibert, O. [Univ. Politecnica de Catalunya, Barcelona (Spain). Dept. d' Enginyeria Quimica]|[Univ. Politecnica de Catalunya, Barcelona (Spain). Centre Tecnologic de Manresa; Cortina, J.-L. [Univ. Politecnica de Catalunya, Barcelona (Spain). Dept. d' Enginyeria Quimica; Ayora, C. [Institut de Ciencies de la Terra Jaume Almera, Barcelona (Spain); Bolzicco, J.; Carrera, J. [Univ. Politecnica de Catalunya, Barcelona (Spain). Dept. d' Enginyeria del Terreny

    2003-07-01

    The objective of the present study was to assess the potential of municipal compost as a carbon provider to sulphate reducing bacteria (SRB) for AMD bio-remediation for use in PRB at high flow rates (>0.1 m/d). Different mixtures where municipal compost was accompanied by limestone and optionally by zero-valent iron were assessed in batch and column experiments to treat acidic waters with high contents of sulphates and eventually of metals. A check of the treated wate was carried out throughout the experiments. At the end of the column experiments, precipitates were withdrawn for SEM, EDS and XRD examination and, for one of the columns, solid digestion and sequential extraction were carried out for chemical analysis. Results showed that waters were cleaned of metals and acidity, but when no supplementation of simple organic carbon compounds was carried out it does not seem from chemical and morphology analysis that mechanisms whereby metal removal occurs was due predominantly to biogenic sulphide generation but to the pH increase, i.e. metal (oxy)hydroxides and carbonates precipitation. These precipitates could sorb other metals onto the surface. Sorption to organic matter could also contribute to some extent to metal removal. When zero-valent iron was present, cementation of copper also occurred. It can be concluded that, as applied in this study, municipal compost assessed under high flow rates was a poorly effective carbon source to support a continuous SRB activity. Then selection of reactive materials for permeable reactive barriers is a critical issue on the step of barrier design and construction. Optimisation of such treatments is very laborious, still being studied up to date and often empirical. In the present laboratory study the municipal compost assessed (typically selected as carbon organic source for PRB treating acid mine drainage) under our experimental conditions was too poor a carbon source to support a continuous SRB activity, due to the high

  10. Superficial drainage studies in open-pit mines

    Drainage studies concerning large open-pit mining projects can be of vital importance throughout the mining activity itself as they may assist in avoiding activity interruptions due to drainage problems, therefore representing substantial savings. These studies should, in fact, be carried out from the initial activity stages and shall be considered in operational, project and planning decisions in order to optimize results and reduce costs. This specific study presents a drainage study systematization proposal, enphasazing economic decision criteria. The authors comment on studies of this nature developed at the Caldas uranium mine - NUCLEBRAS. (D.J.M.)

  11. Water monitoring around the Buchim copper mine drainage system and installation for copper leaching

    Konzulov, Gerasim; Sarafiloski, Sare; Serafimovski, Dalibor; Tasev, Goran

    2015-01-01

    In this paper we would like to present ours latest findings in regards to copper contamination around the Buchim copper mine drainage system and adjacent copper leaching facility. Namelly, several so-called polluting hot-spots around the Buchim copper mine have been determined, which manifested pronounced acidic character of mine waters and increased copper concentrations of up to 800 mg/l Cu. After the leaching facility and closed water system were built, the influence of poll...

  12. Effects of Long-Term Acid-Mine Drainage Contamination on Diversity and Activity of Sulfate-Reducing Bacteria in a Natural Salt Marsh.

    Moreau, J. W.; Banfield, J. F.

    2003-12-01

    Constructed wetlands have been studied as sites or analogs for in situ bioremediation of metal contaminants from acid mine drainage (AMD) or industrial sources (e.g. Webb et al. 1998). Wetlands bioremediation necessarily invokes the ubiquity and robustness of sulfate-reducing bacteria (SRB) to sequester dissolved metals into various poorly soluble metal-sulfides (e.g. PbS, CdS). However, few studies of natural wetlands under long-term ecological forcing by AMD or other contaminant sources are available for context. We are investigating the microbial diversity, mineralogy and geochemistry of a highly contaminated salt marsh along the East Central San Francisco Bay. For nearly a half-century, areas within this marsh have received acidic and/or metal-rich groundwaters from near-surface pyrite tailings (transported there from Iron Mountain Mine, near Redding, CA) and local industrial sources (e.g. paint and explosives manufacturers). Sediment cores (30-40 cm long) were taken from six contaminated sites in the marsh with pH range of ˜2 to ˜8. Previous analyses (URS Corp. 2001) reported As, Cd, Cu, Se, Zn, and Pb present in sediments at extremely high concentrations (100s of ppm), yet our ICP-AES analyses of pore waters showed only As present at concentrations of 10-50 ppb. We infer, from high-resolution transmission electron microscope (HRTEM) studies of biogenic (SRB biofilm) ZnS (Moreau et al. 2003, in review) and marsh sediments, that contaminant metals have been sequestered into aggregates of nanocrystalline metal-sulfides. Continuous-flow isotope ratio mass spectrometer (CF-IRMS) analyses of pore-water sulfate and sedimentary sulfides allow resolution of contributions to dissolved sulfate and sulfide from tailings oxidation and dissimilatory sulfate reduction. Sulfate analyses from subsections of three cores (pH 2-3, 6-7, 7-8, respectively) all yield δ 34S values consistent with bacterial sulfate reduction. We note that all three cores also contain very fine

  13. Quantification of Tinto River Sediment Microbial Communities: Importance of Sulfate-Reducing Bacteria and Their Role in Attenuating Acid Mine Drainage

    Sanchez-Andrea, I.; Knittel, K; Amann, R; Amils, R.; Sanz, J.L.

    2012-01-01

    Tinto River (Huelva, Spain) is a natural acidic rock drainage (ARD) environment produced by the bio-oxidation of metallic sulfides from the Iberian Pyritic Belt. This study quantified the abundance of diverse microbial populations inhabiting ARD-related sediments from two physicochemically contrasting sampling sites (SN and JL dams). Depth profiles of total cell numbers differed greatly between the two sites yet were consistent in decreasing sharply at greater depths. Although catalyzed repor...

  14. Benthic metal fluxes and sediment diagenesis in a water reservoir affected by acid mine drainage: A laboratory experiment and reactive transport modeling

    Torres, E.; Ayora, C.; Jiménez-Arias, J. L.; García-Robledo, E.; Papaspyrou, S.; Corzo, A.

    2014-08-01

    Reservoirs are one of the primary water supply sources. Knowledge of the metal fluxes at the water-sediment interfaces of reservoirs is essential for predicting their ecological quality. Redox oscillations in the water column are promoted by stratification; turnover events may significantly alter metal cycling, especially in reservoirs impacted by acid mine drainage (AMD). To study this phenomenon, an experiment was performed under controlled laboratory conditions. Sediment cores from an AMD-affected reservoir were maintained in a tank with reservoir water for approximately two months and subjected to alternating oxic-hypoxic conditions. A detailed metal speciation in solid phases of the sediment was initially performed by sequential extraction, and pore water was analyzed at the end of each redox period. Tank water metals concentrations were systematically monitored throughout the experiment. The experimental results were then used to calibrate a diffusion-reaction model and quantify the reaction rates and sediment-water fluxes. Under oxic conditions, pH, Fe and As concentrations decreased in the tank due to schwertmannite precipitation, whereas the concentrations of Al, Zn, Cu, Ni, and Co increased due to Al(OH)3 and sulfide dissolution. The reverse trends occurred under hypoxic conditions. Under oxic conditions, the fluxes calculated by applying Fick’s first law to experimental concentration gradients contradicted the fluxes expected based on the evolution of the tank water. According to the reactive transport calculations, this discrepancy can be attributed to the coarse resolution of sediment sampling. The one-cm-thick slices failed to capture effectively the notably narrow (1-2 mm) concentration peaks of several elements in the shallow pore water resulting from sulfide and Al(OH)3 dissolution. The diffusion-reaction model, extended to the complete year, computed that between 25% and 50% of the trace metals and less than 10% of the Al that precipitated under

  15. Influence of waterfall aeration and seasonal temperature variation on the iron and arsenic attenuation rates in an acid mine drainage system

    Dramatic seasonal changes in water chemistry and precipitate mineralogy associated with acid-mine drainage (AMD) in the waterfall and creek sections of the Chinkuashih area, northern Taiwan were investigated. Special attention has been paid to the kinetic effects of seasonal temperature variation and waterfall aeration. Precipitation of schwertmannite associated with removal of metals and As are indicated by delicate growth microstructures on precipitate surfaces, X-ray diffraction data, and downstream reductions of metal and As concentrations. Geochemical modeling suggested a downstream increase of the degree of saturation/supersaturation with respect to schwertmannite in the waterfall section, which can be attributed to high Fe2+ oxidation rates. The waterfall section was characterized by high rates and model rate constants of Fe2+ oxidation (6.1–6.7 × 10−6 mol L−1 s−1 and 2.7–2.9 × 10−2 s−1) and Fe (schwertmannite) precipitation (1.7–2.1 × 10−6 mol L−1 s−1 and 3.5–4.1 × 10−7 mol L−1 s−1). A high As sorption rate (4.7–6.3 × 10−9 mol L−1 s−1) and low As distribution coefficient (7.9–11.8 × 10−9 mol−1 L) were observed. The creek section showed up to 1–2 orders of magnitude slower rates and lower rate constants than the waterfall section and had seasonal variations comparable to those in areas polluted by AMD elsewhere. The summer rates were 4–5 times higher than the winter rates in the creek section, and are largely attributed to a temperature effect. In contrast, the seasonal differences in rate and rate constant were small in the waterfall section. Several factors associated with the waterfall aeration in addition to elevated temperature and As concentration enhanced Fe and As attenuation in the waterfall section. The waterfall effects on Fe precipitation rate were enhanced when the flow rate was large in the winter. Despite the remarkable removal of metals and As by the rapid precipitation of As

  16. Emprego de coberturas secas no controle da drenagem ácida de mina: estudos em campo Use of dry cover systems to control acid mine drainage: field studies

    Sérgio Luciano Galatto

    2007-06-01

    Full Text Available No sul catarinense, cristais de pirita associados a rejeitos de beneficiamento de carvão mineral, quando alterados, desencadeiam o processo conhecido como drenagem ácida de mina (DAM. Este trabalho objetivou avaliar a eficiência de três sistemas de coberturas secas sobre estes rejeitos, como uma opção para o controle da DAM. Agentes neutralizantes da DAM como a cinza pesada e o calcário foram misturados com os rejeitos ou dispostos acima destes. Para reduzir a infiltração de água e difusão de oxigênio no meio, foi empregada uma camada de 50 cm de solo silte-argiloso compactado. Os experimentos foram monitorados por um ano, sendo analisados nos lixiviados alguns parâmetros indicadores da DAM, além da presença de bactérias ferro-oxidantes e sulfato-redutoras. Os resultados obtidos indicaram uma boa eficiência na prevenção da DAM de dois dos três sistemas de coberturas pesquisados.In the southern of the Santa Catarina state, the weathering and oxidation of pyrite-containing coal has been the major agent of Acid Mine Drainage (AMD production. The purpose of this study was to verify the efficiency of three different cover systems to inhibit AMD. Experiments were built in field lysimeters with alkaline agents - bottom ash and limestone - placed over or mixed with fresh coal waste. To reduce the water infiltration rates and oxygen diffusion 50 cm of compact mud soil layer was put over waste. The top cover was constituted by 10 cm of the same soil, mixed with bottom ash. During one year, these experiments have been monitored through chemical (pH, Eh, Fe2+, Fe total, Al, Ca, Mg, Zn, Pb and Mn and microbiological (Thiobacilus ferroxidans presence composition of effluents. The results indicated that two of three cover systems employed were efficient on AMD prevention.

  17. Evaporation of acid mine water with mechanical vapor recompression

    Ylitolva, T. (Taija)

    2016-01-01

    Acid mine water formation is a wide environmental problem that occurs especially in mines, but also anywhere else where the bedrock minerals produce acid when exposed to oxygenated waters due to excavation. Iron containing sulfide minerals are particularly problematic due to their efficient ability to produce acid. In a favorable case, acid mine drainage and process waters from mining industry can also be valuable sources of metals or other raw materials. Potential methods for the utilization...

  18. Remediação de drenagem ácida de mina usando zeólitas sintetizadas a partir de cinzas leves de carvão Remediation of acid mine drainage using zeolites synthesized from coal fly ash

    Denise Alves Fungaro

    2006-07-01

    Full Text Available Zeolitic material was synthesized from coal fly ashes (baghouse filter fly ash and cyclone filter fly ash by hydrothermal alkaline activation. The potential application of the zeolitic product for decontamination of waters from acid mine drainage was evaluated. The results showed that a dose of 30 g L-1 of zeolitic material allowed the water to reach acceptable quality levels after treatment. Both precipitation and cation-exchange processes accounted for the reduction in the pollutant concentration in the treated waters.

  19. Processos físico-químicos em drenagem ácida de mina em mineração de carvão no sul do Brasil Physico-chemical processes in acid mine drainage in coal mining, south Brazil

    Veridiana Polvani Campaner; Wanilson Luiz-Silva

    2009-01-01

    Acid mine drainage generated from coal mine showed a pH of 3.2, high concentrations of SO4(2-), Al, Fe, Mn, Zn and minor As, Cd, Co, Cr, Cu, Ni and Pb. The major reduction in the concentration occurred for Al, As, Cr, Fe and Pb after the treatment with CaO. The evolution of these acid waters within the tributary stream showed decreasing concentration for all soluble constituents, except Al. This natural attenuation was controlled by pH (6.4 to 10.8) as a result of concurrent mixing with tribu...

  20. Operational Lessons Learned During Bioreactor Demonstrations for Acid Rock Drainage Treatment

    The U.S. Environmental Protection Agency’s Mine Waste Technology Program (MWTP) has emphasized the development of biologically-based treatment technologies for acid rock drainage (ARD). Progressively evolving technology demonstrations have resulted in significant advances in sul...

  1. An empirical method for estimating instream pre-mining pH and dissolved Cu concentration in catchments with acidic drainage and ferricrete

    Nimick, D.A.; Gurrieri, J.T.; Furniss, G.

    2009-01-01

    Methods for assessing natural background water quality of streams affected by historical mining are vigorously debated. An empirical method is proposed in which stream-specific estimation equations are generated from relationships between either pH or dissolved Cu concentration in stream water and the Fe/Cu concentration ratio in Fe-precipitates presently forming in the stream. The equations and Fe/Cu ratios for pre-mining deposits of alluvial ferricrete then were used to reconstruct estimated pre-mining longitudinal profiles for pH and dissolved Cu in three acidic streams in Montana, USA. Primary assumptions underlying the proposed method are that alluvial ferricretes and modern Fe-precipitates share a common origin, that the Cu content of Fe-precipitates remains constant during and after conversion to ferricrete, and that geochemical factors other than pH and dissolved Cu concentration play a lesser role in determining Fe/Cu ratios in Fe-precipitates. The method was evaluated by applying it in a fourth, naturally acidic stream unaffected by mining, where estimated pre-mining pH and Cu concentrations were similar to present-day values, and by demonstrating that inflows, particularly from unmined areas, had consistent effects on both the pre-mining and measured profiles of pH and Cu concentration. Using this method, it was estimated that mining has affected about 480 m of Daisy Creek, 1.8 km of Fisher Creek, and at least 1 km of Swift Gulch. Mean values of pH decreased by about 0.6 pH units to about 3.2 in Daisy Creek and by 1-1.5 pH units to about 3.5 in Fisher Creek. In Swift Gulch, mining appears to have decreased pH from about 5.5 to as low as 3.6. Dissolved Cu concentrations increased due to mining almost 40% in Daisy Creek to a mean of 11.7 mg/L and as much as 230% in Fisher Creek to 0.690 mg/L. Uncertainty in the fate of Cu during the conversion of Fe-precipitates to ferricrete translates to potential errors in pre-mining estimates of as much as 0.25 units

  2. Thermal behaviour of natural and synthetic iron precipitates from mine drainage

    Pulišová, Petra; Máša, B.; Michalková, E.; Večerníková, Eva; Maříková, Monika; Bezdička, Petr; Murafa, Nataliya; Šubrt, Jan

    2014-01-01

    Roč. 116, č. 2 (2014), s. 625-632. ISSN 1388-6150 R&D Projects: GA MŠk 7AMB12SK155 Institutional support: RVO:61388980 Keywords : Thermogravimetry * Differential thermal analysis * X-ray diffraction analysis * Acid mine drainage * Iron precipitates * Precipitation with urea Subject RIV: CA - Inorganic Chemistry Impact factor: 2.042, year: 2014

  3. Coal properties and mine operational factors that impact gas drainage

    Black, D.J.; Aziz, N.I. [Wollongong Univ., Wollongong, NSW (Australia)

    2010-07-01

    Areas of increased gas content, which are difficult to drain, are encountered in many underground coal mines in Australia. Several factors have the potential to influence the overall efficiency and effectiveness of gas drainage from the mined coal seam. This paper reported on a study that was conducted at an operating coal mine in the Bulli seam of Australia's Illawarra coal measures. Gas composition in the mining domain ranged from almost pure methane in the east to almost pure carbon dioxide in the west. Gas production data from many inseam gas drainage boreholes was evaluated relative to a variety of coal properties and mine operational factors to determine their impact on gas production performance. The study showed that although the design of the boreholes and the drainage time had some impact on gas production, the coal properties were found to have the greatest impact. In particular, coal rank, ash content, gas content, seam thickness and gas composition all had an influence on gas production. The total gas in place and degree of saturation had the most significant impact on coal seam gas production performance. Several recommendations were made to optimize gas drainage productivity. 3 refs., 12 figs.

  4. Hydrogeochemistry of groundwater seepage into an acidic mining lake

    Hofmann, Hilmar; Lessmann, Dieter

    2006-01-01

    In the Lusatian Lignite Mining District 259 mining lakes (ML) are originating from abandoned mines. They show significant differences in their morphometry and are mostly strong acidic (HEMM et al. 2002). The oxidation of sedimentary pyrite in aerated dump sediments (tertiary sands) forms acid mine drainage rich in iron and sulphate which is still present after filling the pit and has decisive influence on matter flux, biocoenotic development and possible uses, e.g. recreation or water supply ...

  5. Molybdenum and zinc stable isotope variation in mining waste rock drainage and waste rock at the Antamina mine, Peru.

    Skierszkan, E K; Mayer, K U; Weis, D; Beckie, R D

    2016-04-15

    The stable isotope composition of molybdenum (Mo) and zinc (Zn) in mine wastes at the Antamina Copper-Zn-Mo mine, Peru, was characterized to investigate whether isotopic variation of these elements indicated metal attenuation processes in mine drainage. Waste rock and ore minerals were analyzed to identify the isotopic composition of Mo and Zn sources, namely molybdenites (MoS2) and sphalerites (ZnS). Molybdenum and Zn stable isotope ratios are reported relative to the NIST-SRM-3134 and PCIGR-1 Zn standards, respectively. δ(98)Mo among molybdenites ranged from -0.6 to +0.6‰ (n=9) while sphalerites showed no δ(66)Zn variations (0.11±0.01‰, 2 SD, n=5). Mine drainage samples from field waste rock weathering experiments were also analyzed to examine the extent of isotopic variability in the dissolved phase. Variations spanned 2.2‰ in δ(98)Mo (-0.1 to +2.1‰) and 0.7‰ in δ(66)Zn (-0.4 to +0.3‰) in mine drainage over a wide pH range (pH2.2-8.6). Lighter δ(66)Zn signatures were observed in alkaline pH conditions, which was consistent with Zn adsorption and/or hydrozincite (Zn5(OH)6(CO3)2) formation. However, in acidic mine drainage Zn isotopic compositions reflected the value of sphalerites. In addition, molybdenum isotope compositions in mine drainage were shifted towards heavier values (0.89±1.25‰, 2 SD, n=16), with some overlap, in comparison to molybdenites and waste rock (0.13±0.82‰, 2 SD, n=9). The cause of heavy Mo isotopic signatures in mine drainage was more difficult to resolve due to isotopic heterogeneity among ore minerals and a variety of possible overlapping processes including dissolution, adsorption and secondary mineral precipitation. This study shows that variation in metal isotope ratios are promising indicators of metal attenuation. Future characterization of isotopic fractionation associated to key environmental reactions will improve the power of Mo and Zn isotope ratios to track the fate of these elements in mine drainage

  6. Abatement of acid mine drainage by encapsulation of acid-producing geological material. Final research report, 1 August 1990-31 October 1992

    A novel coating technology was developed to prevent pyrite oxidation and acid production in coal waste. The mechanism underlying this technology involves leaching coal waste with a coating solution composed of H2O2, KH2PO4, and sodium acetate (NaAC). During the leaching process, H2O2 oxidizes pyrite and produces Fe3+ so that iron phosphate precipitates as a coating on pyrite surfaces. The purpose of NaAC in the coating solution is to eliminate the inhibitory effect of the protons, produced during pyrite oxidation, on the precipitation of iron phosphate. In the study, it was shown that iron phosphate coatings on pyrite surfaces could be established by consuming 5% to 10% of the available pyrite, under a wide range of conditions. It was also demonstrated in the study that iron phosphate coatings on pyrite surfaces could prevent pyrite oxidation and acid production in coal waste

  7. 40 CFR 434.40 - Applicability; description of the alkaline mine drainage subcategory.

    2010-07-01

    ... alkaline mine drainage subcategory. 434.40 Section 434.40 Protection of Environment ENVIRONMENTAL..., BCT LIMITATIONS AND NEW SOURCE PERFORMANCE STANDARDS Alkaline Mine Drainage § 434.40 Applicability; description of the alkaline mine drainage subcategory. The provisions of this subpart are applicable...

  8. Use of wetlands for the treatment of acidic mining drainage: the processes in the wetland; Utilizacion de humedales para el tratamiento de aguas acidas de mina: procesos que tienen lugar en el humedal

    Gonzalez Lastra, M.; Loredo Perez, J. [Departamento de Explotacion y Prospeccion de Minas. Escuela de Minas, Universidad de Oviedo, Oviedo (Spain)

    1995-04-01

    Wetlands constitute an alternative method for the treatment of acidic mining drainage, through the utilization of some plant species complex physico-chemical and biological processes take place, producing and improvement of the quality of waters moving through. The inherent characteristics of a wetland in operation will originate an horizontal zonation as for the quality of waters due to their progressive ameliorations of pH increase and heavy metals concentration decreases, anyway a vertical zonation, giving rise to oxidation and reduction zones on the wetland. From the different physical processes occurring on the wetland, the plant roots filtering, the dilution of effluents with superficial and underground waters and aeration phenomena can be considered very important. Oxidation, hydrolysis and sulphate reduction constitute important chemical processes leading to the removal of heavy metals from contaminated effluents. Wetlands have plants as sphagnum, typha and algae advantageous for the treatment of acidic waters provided that they retain heavy metals in their tissues and the contribute furthermore to modify the substrate conditions favoring the creation of reduction zones. The aerobic-anaerobic mixed systems are from the different wetland types those are prevailing because of the advantages of sulphate reduction as contrasted with oxides precipitation for the removal of heavy metals. Wetlands although are not the panacea for the treatment of acidic mining waters they offer advantages and some disadvantages too, over other treatment methods, and they constitute a real alternative for the conventional methods of chemical neutralization. (Author)

  9. Characterization of anthropogenic and natural sources of acid rock drainage at the Cinnamon Gulch abandoned mine land inventory site, Summit County, Colorado

    Bird, D.A.

    2003-01-01

    Colorado's Cinnamon Gulch releases acid rock drainage (ARD) from anthropogenic and natural sources. In 2001, the total discharge from Cinnamon Gulch was measured at 1.02 cfs (29 L/s) at base flow and 4.3 cfs (122 L/s) at high flow (spring runoff). At base flow, natural sources account for 98% of the discharge from the watershed, and about 96% of the chemical loading. At high flow, natural sources contribute 96% of discharge and 92 to 95% of chemical loading. The pH is acidic throughout the Cinnamon Gulch watershed, ranging from 2.9 to 5.4. At baseflow, nearly all of the trace metals analyzed in the 18 samples exceeded state hardness-dependent water quality standards for aquatic life. Maximum dissolved concentrations of selected constituents included 16 mg/ L aluminum, 15 mg/L manganese, 40 mg/L iron, 2 mg/L copper, 560 ??g/L lead, 8.4 mg/L zinc, and 300 mg/L sulfate. Average dissolved concentrations of selected metals at baseflow were 5.5 mg/L aluminum, 5.5 mg/L manganese, 14 ??g/L cadmium, 260 ??g/L copper, 82 ??g/L lead, and 2.8 mg/L zinc.

  10. Application of geochemical modeling and hydrologic techniques to interpret sources, mixing and evolution of mine drainage

    The geochemical code PHREEQC was used in an investigation of potential recharge sources to a flooded pit affected by acid drainage. Pit water quality had been alkaline with low metals and moderate dissolved aluminum, manganese and sulfate. The recharge area for the flooded pit included a coal refuse pile, flooded underground mine works, flyash pile, surface mine spoil and a sediment pond. A set of water quality samples were analyzed for mine drainage parameters, major dissolved constituents and some trace metals. These data were inverse modeled using the flooded pit water as the end product. Mixing of several possible sources and single source recharge scenarios were run along the inferred ground water flow path. Mixing of coal refuse pile leachate with leakage from the sediment pond or mine spoil provided acceptable characterization as the principal sources controlling pit water chemistry. These results were consistent with the ground water flow path interpreted from water level measurements in wells, structure, air photos and mining history. The dominant rock-water interactions modeled were dissolution of carbonate minerals and stored sulfate salts. Simple binary mixing was not adequate to describe the reaction path and resultant water chemistry. Geochemical models were useful for assessing mine drainage sources, and can be included as one of a collection of investigative tools

  11. Acidophilic, Heterotrophic Bacteria of Acidic Mine Waters

    Wichlacz, Paul L.; Unz, Richard F.

    1981-01-01

    Obligately acidophilic, heterotrophic bacteria were isolated both from enrichment cultures developed with acidic mine water and from natural mine drainage. The bacteria were grouped by the ability to utilize a number of organic acids as sole carbon sources. None of the strains were capable of chemolithotrophic growth on inorganic reduced iron and sulfur compounds. All bacteria were rod shaped, gram negative, nonencapsulated, motile, capable of growth at pH 2.6 but not at pH 6.0, catalase and ...

  12. Quantification of Tinto River sediment microbial communities: importance of sulfate-reducing bacteria and their role in attenuating acid mine drainage.

    Sánchez-Andrea, Irene; Knittel, Katrin; Amann, Rudolf; Amils, Ricardo; Sanz, José Luis

    2012-07-01

    Tinto River (Huelva, Spain) is a natural acidic rock drainage (ARD) environment produced by the bio-oxidation of metallic sulfides from the Iberian Pyritic Belt. This study quantified the abundance of diverse microbial populations inhabiting ARD-related sediments from two physicochemically contrasting sampling sites (SN and JL dams). Depth profiles of total cell numbers differed greatly between the two sites yet were consistent in decreasing sharply at greater depths. Although catalyzed reporter deposition fluorescence in situ hybridization with domain-specific probes showed that Bacteria (>98%) dominated over Archaea (water column (pH 2.5 and +400 mV), the most abundant organisms were identified as iron-reducing bacteria: Acidithiobacillus spp. and Acidiphilium spp., probably related to the higher iron solubility at low pH. At the JL dam, characterized by a banded sediment with higher pH (4.2 to 6.2), more reducing redox potential (-210 mV to 50 mV), and a lower solubility of iron, members of sulfate-reducing genera Syntrophobacter, Desulfosporosinus, and Desulfurella were dominant. The latter was quantified with a newly designed CARD-FISH probe. In layers where sulfate-reducing bacteria were abundant, pH was higher and redox potential and levels of dissolved metals and iron were lower. These results suggest that the attenuation of ARD characteristics is biologically driven by sulfate reducers and the consequent precipitation of metals and iron as sulfides. PMID:22544246

  13. Mining drainage treatment from the horizon 830 in mine Sasa by simulation anaerobic wetland

    Stojanovska, Marija; Golomeova, Mirjana; Golomeov, Blagoj; Zendelska, Afrodita; Krstev, Aleksandar

    2012-01-01

    The results of measurements of the quality of mining drainage from the active horizon 830 in Mine SASA show increased concentrations of heavy and toxic metals. The paper shows results of mining drainage treating samples from horizon 830 by simulation anaerobic wetland. Used two types of limestone, one of which is the content of CaCO3 - 93-95%, and the other > 98% CaCO3. As organic matter is used a fractured surrounding forest. The results show that the application of this type of treatmen...

  14. Jarosite versus Soluble Iron-Sulfate Formation and Their Role in Acid Mine Drainage Formation at the Pan de Azúcar Mine Tailings (Zn-Pb-Ag), NW Argentina

    Jesica Murray; Alicia Kirschbaum; Bernhard Dold; Edi Mendes Guimaraes; Elisa Pannunzio Miner

    2014-01-01

    Secondary jarosite and water-soluble iron-sulfate minerals control the composition of acid mine waters formed by the oxidation of sulfide in tailings impoundments at the (Zn-Pb-Ag) Pan de Azúcar mine located in the Pozuelos Lagoon Basin (semi-arid climate) in Northwest (NW) Argentina. In the primary zone of the tailings (9.5 wt % pyrite-marcasite) precipitation of anglesite (PbSO4), wupatkite ((Co,Mg,Ni)Al2(SO4)4) and gypsum retain Pb, Co and Ca, while mainly Fe2+, Zn2+, Al3+, Mg2+, As3+/5+ ...

  15. COMPARISON OF DATA FROM SYNTHETIC LEACHATE AND DIRECT SAMPLING OF ACID DRAINAGE FROM MINE WASTES: IMPLICATIONS FOR MERCURY TRANSPORT AND WASTE MANAGEMENT

    The Sulphur Bank Mercury Mine (SBMM) in Lake County, California operated from the 1860s through the 1950's. Mining for sulfur started with surface operations and progressed to shaft, then open pit techniques to obtain mercury. Mining has resulted in deposition of approximately ...

  16. Fe and Mn removal from mining drainage using goaf filling materials obtained from coal mining process.

    Zhang, Liping; Chen, Aolei; Qu, Hongbin; Xu, Shouqiang; Zhang, Xue; He, Xuwen

    2015-01-01

    Coal gangue, sandy soil and clay (mass ratio 45:4:1) as goaf filling materials acquired from coal mining processes were applied to remove Fe and Mn effectively from mining drainage. The results of an adsorption kinetic study showed that the Fe adsorption equation was y=21.454y+8.4712, R2=0.9924 and the Mn adsorption equation was y=7.5409x+0.905, R2=0.9957. Meanwhile, the goaf filling materials had low desorption capacity (Fe 6.765 μg/g, Mn 1.52 μg/g) and desorption ratio (Fe 8.98%, Mn 11.04%). Experiments demonstrated that Fe and Mn from mining drainage could be removed stably at a flow rate of 1.2 L/min, Fe inlet concentration of less than 40 mg/L, Mn inlet concentration of less than 2 mg/L and neutral or alkaline conditions. During a procedure of continuous experiments, the effluent quality could meet the requirement of the 'Code for Engineering Design of Sewage Regeneration-GB503352-2002'. A real-application project using goaf filling materials to treat mining drainage in Shendong coal mine showed that the average cost per ton of mining drainage was about 0.55 RMB, which could bring about considerable economic benefit for coal mining enterprises. PMID:26606087

  17. Chemical and mineralogical changes of waste and tailings from the Murgul Cu deposit (Artvin, NE Turkey): implications for occurrence of acid mine drainage.

    Sağlam, Emine Selva; Akçay, Miğraç

    2016-04-01

    Being one of the largest copper-producing resources in Turkey, the Murgul deposit has been a source of environmental pollution for very long time. Operated through four open pits with an annual production of about 3 million tons of ore at an average grade of about 0.5 % Cu, the deposit to date has produced an enormous pile of waste (exceeding 100 million tons) with tailings composed of 36 % SiO2, 39 % Fe2O3 and 32 % S, mainly in the form of pyrite and quartz. Waters in the vicinity of the deposit vary from high acid-acid (2.71-3.85) and high-extremely metal rich (34.48-348.12 mg/l in total) in the open pits to near neutral (6.51-7.83) and low metal (14.39-973.52 μg/l in total) in downstream environments. Despite low metal contents and near neutral pH levels of the latter, their suspended particle loads are extremely high and composed mainly of quartz and clay minerals with highly elevated levels of Fe (3.5 to 24.5 % Fe2O3; 11 % on average) and S (0.5 to 20.6 % S; 7 % on average), showing that Fe is mainly in the form of pyrite and lesser hematite. They also contain high concentrations of As, Au, Ba, Cu, Pb, and Zn. Waters collected along the course of polluted drainages are supersaturated with respect to Fe phases such as goethite, hematite, maghemite, magnetite, schwertmannite and ferrihydrite. Secondary phases such as Fe-sulphates are only found near the pits, but not along the streams due to neutral pH conditions, where pebbles are covered and cemented by Fe-oxides and hydroxides indicating that oxidation of pyrite has taken place especially at times of low water load. It follows, then, that the pyrite-rich sediment load of streams fed by the waste of the Murgul deposit is currently a big threat to the aquatic life and environment and will continue to be so even after the closure of the deposit. In fact, the oxidation will be enhanced and acidity increased due to natural conditions, which necessitates strong remedial actions to be taken. PMID:26637995

  18. Processos físico-químicos em drenagem ácida de mina em mineração de carvão no sul do Brasil Physico-chemical processes in acid mine drainage in coal mining, south Brazil

    Veridiana Polvani Campaner

    2009-01-01

    Full Text Available Acid mine drainage generated from coal mine showed a pH of 3.2, high concentrations of SO4(2-, Al, Fe, Mn, Zn and minor As, Cd, Co, Cr, Cu, Ni and Pb. The major reduction in the concentration occurred for Al, As, Cr, Fe and Pb after the treatment with CaO. The evolution of these acid waters within the tributary stream showed decreasing concentration for all soluble constituents, except Al. This natural attenuation was controlled by pH (6.4 to 10.8 as a result of concurrent mixing with tributary stream and reaction with local bedrock that contains limestone. Aluminum increasing concentration during this evolution seems to be related to an input of Al-enriched waters due to the leaching of silicate minerals in alkaline conditions.

  19. Exploration drilling for pre-mining gas drainage in coal mines

    High natural gas content in coal seams and low gas drainage efficiency are the basic issues to be addressed in order to ensure coal mining safety. A great number of wells being drilled within various gas drainage techniques significantly increase the costs of coal mining and do not reduce the gas content levels within the coal beds up to the required parameters in a short period of time. The integrated approach toward exploration well spacing applied at the stage of project development could make it possible to consider coal seam data to provide more effective gas drainage not only ahead of mining but also during further gas content reduction and commercial production of methane. The comparative analysis of a closely spaced grid of exploration program compiled in accordance with the recommendations on applying mineral reserves classification and inferred resources of coal and shale coal deposits and currently effective stimulation radius proves the necessity and possibility to consider exploration well data for gas drainage. Pre-mining gas drainage could ensure the safety of mining operations

  20. Exploration drilling for pre-mining gas drainage in coal mines

    Shubina, E. A.; Brylin, V. I.; Lukyanov, V. G.; Korotchenko, T. V.

    2015-02-01

    High natural gas content in coal seams and low gas drainage efficiency are the basic issues to be addressed in order to ensure coal mining safety. A great number of wells being drilled within various gas drainage techniques significantly increase the costs of coal mining and do not reduce the gas content levels within the coal beds up to the required parameters in a short period of time. The integrated approach toward exploration well spacing applied at the stage of project development could make it possible to consider coal seam data to provide more effective gas drainage not only ahead of mining but also during further gas content reduction and commercial production of methane. The comparative analysis of a closely spaced grid of exploration program compiled in accordance with the recommendations on applying mineral reserves classification and inferred resources of coal and shale coal deposits and currently effective stimulation radius proves the necessity and possibility to consider exploration well data for gas drainage. Pre-mining gas drainage could ensure the safety of mining operations.

  1. EVALUATION OF A METHOD USING COLLOIDAL GAS APHRONS TO REMEDIATE METALS-CONTAMINATED MINE DRAINAGE WATERS

    R. Williams Grimes

    2002-06-01

    Experiments were conducted in which three selected metals-contaminated mine drainage water samples were treated by chemical precipitation followed by flotation using colloidal gas aphrons (CGAs) to concentrate the precipitates. Drainage water samples used in the experiments were collected from an abandoned turn-of-the-century copper mine in south-central Wyoming, an inactive gold mine in Colorado's historic Clear Creek mining district, and a relatively modern gold mine near Rapid City, South Dakota. The copper mine drainage sample was nearly neutral (pH 6.5) while the two gold mine samples were quite acidic (pH {approx}2.5). Metals concentrations ranged from a few mg/L for the copper mine drainage to several thousand mg/L for the sample from South Dakota. CGAs are emulsions of micrometer-sized soap bubbles generated in a surfactant solution. In flotation processes the CGA microbubbles provide a huge interfacial surface area and cause minimal turbulence as they rise through the liquid. CGA flotation can provide an inexpensive alternative to dissolved air flotation (DAF). The CGA bubbles are similar in size to the bubbles typical of DAF. However, CGAs are generated at ambient pressure, eliminating the need for compressors and thus reducing energy, capital, and maintenance costs associated with DAF systems. The experiments involved precipitation of dissolved metals as either hydroxides or sulfides followed by flotation. The CGAs were prepared using a number of different surfactants. Chemical precipitation followed by CGA flotation reduced contaminant metals concentrations by more than 90% for the copper mine drainage and the Colorado gold mine drainage. Contaminant metals were concentrated into a filterable sludge, representing less than 10% of the original volume. CGA flotation of the highly contaminated drainage sample from South Dakota was ineffective. All of the various surfactants used in this study generated a large sludge volume and none provided a

  2. Acid drainages of the pyritic sterile from the Pocos de Caldas uranium mine: environmental interpretation and implications; Drenagens acidas do esteril piritoso da mina de uranio de Pocos de Caldas: interpretacao e implicacoes ambientais

    Souza, Vicente Paulo de

    1995-12-01

    Considering the planned closure of the first uranium mine and milling plant operating in Brazil, located in the Pocos de Caldas Plateau, in the State of Minas Gerais, in the next two years, there is the need to obtain basic information for its decommissioning. Special attention has been directed to the following critical areas: open pit, tailing, dam and waste rock piles, because these are the main sources of acid drainage generation. These waters cannot be allowed to flow in the external environment because in addition to sulphuric acid, there is a number of elements in concentration above those allowed by regulations. Among the waste piles (bota-foras BF) two of them BF-4 and BF-8, are in a process of acid generation, thus requiring more attention. The objective of this work was to simulate at the laboratory scale the oxidation and the reduction zones of BF-4. The experiments were conducted in acrylic columns, where the waste sample was kept under aerated and saturated conditions, in different columns. The control of the chemical (solubilized chemical species), physico-chemical (redox potential, pH, conductivity) and biological (bacterial activity) parameters has been carried out on the acid solutions generated by the chemical and biological reactions that occur at the waste. Although the results refer to a four month period, some relevant points can be highlighted, which will serve as a basis for further research. The mineralogical characterization identified the existence of other sulphides associated to pyrite with lower oxidation potential than the latter. The results obtained with the biological characterization for the two conditions studied revealed that the bacterial activity is more intense in the region in contact with air, than in saturated region. (author) 30 refs., 29 figs., 8 tabs.

  3. Water monitoring around the Buchim copper mine drainage system

    Serafimovski, Todor; Nikolov, Nikolajco; Konzulov, Gerasim; Tasev, Goran; Sarafiloski, Sare

    2013-01-01

    Two hot-spot sources are representative for the Buchim mine drainage system. The first one is the waste dump, which produces an average flow of 15-20 l/s with low pH value (3,6-5,5) and 450-850 mg/l Cu. The second source one is the hydrotailing dam near the Topolnica River where monitored parameters of waters distinguish themselves by incre-ased pH values from 6.2 up to 7.6 and increased concentrations of suspended ma¬t¬ters (7-466 mg/l) while the copper concentration remained below the MDK l...

  4. Acid mine water aeration and treatment system

    Ackman, Terry E.; Place, John M.

    1987-01-01

    An in-line system is provided for treating acid mine drainage which basically comprises the combination of a jet pump (or pumps) and a static mixer. The jet pump entrains air into the acid waste water using a Venturi effect so as to provide aeration of the waste water while further aeration is provided by the helical vanes of the static mixer. A neutralizing agent is injected into the suction chamber of the jet pump and the static mixer is formed by plural sections offset by 90 degrees.

  5. Inorganic pigments made from the recycling of coal mine drainage treatment sludge.

    Marcello, R R; Galato, S; Peterson, M; Riella, H G; Bernardin, A M

    2008-09-01

    Continuous industrial development increases energy consumption and, consequently, the consumption of fossil fuels. Coal mineral has been used in Brazil as a solid fuel for thermoelectric generators for several years. However, coal exploitation affects the environment intensely, mainly because Brazilian coal contains excess ash and pyrite (iron disulfide). According to the local coal industry syndicate, the average annual coal run per mine is 6 million ton/year; 3.5 million ton/year are rejected and disposed of in landfills. Besides pyrite, Brazilian coal contains Mn, Fe, Cu, Pb, Zn, Ge, Se, and Co. Additionally, the water used for coal beneficiation causes pyrite oxidation, forming an acid mine drainage (AMD). This drainage solubilizes the metals, transporting them into the environment, making treatment a requirement. This work deals with the use of sedimented residue from treated coal mine drainage sludge to obtain inorganic pigments that could be used in the ceramic industry. The residue was dried, ground and calcined ( approximately 1250 degrees C). The calcined pigment was then micronized (D(50) approximately 2mum). Chemical (XRF), thermal (DTA/TG), particle size (laser), and mineralogical (XRD) analyses were carried out on the residue. After calcination and micronization, mineralogical analyses (XRD) were used to determine the pigment structure at 1250 degrees C. Finally, the pigments were mixed with transparent glaze and fired in a laboratory roller kiln (1130 degrees C, 5min). The results were promising, showing that brown colors can be obtained with pigments made by residues. PMID:17703872

  6. Gas drainage from different mine areas:optimal placement of drainage systems for deep coal seams with high gas emissions

    Ping Lu; Ping Li; Jian Chen; Chuijin Zhang; Junhua Xue; Tao Yu

    2015-01-01

    The techniques of stress relief mining in low-permeability coal seams and pillarless gob side retained roadway entry using Y-type ventilation and gas drainage systems were developed to control gas outbursts and applied successfully. However, as the mining depth increasing, parts of the gas drainage system are not suitable for mines with high gas emissions. Because larger mining depths cause higher ground stresses, it becomes extremely difficult to maintain long gob side roadways. The greater deformation suffered by the roadway is not favorable for borehole drilling for continuous gas drainage. To solve these problems, Y-type ventilation and gas drainage systems installed from a roof roadway were designed for drainage optimization. This system was designed based on a gas-enrichment zone analysis developed from mining the 11-2 coal seam in the Zhuji Mine at Huainan, Anhui Province, China. The method of Y-type gas extraction from different mine areas was applied to the panel 1112(1) in the Zhuji Mine. The absolute gas emission rate was up to 116.3 m3/min with an average flow of 69.1 m3/min at an average drainage concentration of nearly 85%. After the Y-type method was adopted, the concentration of gas in the return air was 0.15%–0.64%, averaging 0.39%with a ventilation rate of 2100–2750 m3/min. The gas management system proved to be efficient, and the effective gas control allowed safe production to continue.

  7. Geochemical Characterization of Mine Waste, Mine Drainage, and Stream Sediments at the Pike Hill Copper Mine Superfund Site, Orange County, Vermont

    Piatak, Nadine M.; Seal, Robert R., II; Hammarstrom, Jane M.; Kiah, Richard G.; Deacon, Jeffrey R.; Adams, Monique; Anthony, Michael W.; Briggs, Paul H.; Jackson, John C.

    2006-01-01

    The Pike Hill Copper Mine Superfund Site in the Vermont copper belt consists of the abandoned Smith, Eureka, and Union mines, all of which exploited Besshi-type massive sulfide deposits. The site was listed on the U.S. Environmental Protection Agency (USEPA) National Priorities List in 2004 due to aquatic ecosystem impacts. This study was intended to be a precursor to a formal remedial investigation by the USEPA, and it focused on the characterization of mine waste, mine drainage, and stream sediments. A related study investigated the effects of the mine drainage on downstream surface waters. The potential for mine waste and drainage to have an adverse impact on aquatic ecosystems, on drinking- water supplies, and to human health was assessed on the basis of mineralogy, chemical concentrations, acid generation, and potential for metals to be leached from mine waste and soils. The results were compared to those from analyses of other Vermont copper belt Superfund sites, the Elizabeth Mine and Ely Copper Mine, to evaluate if the waste material at the Pike Hill Copper Mine was sufficiently similar to that of the other mine sites that USEPA can streamline the evaluation of remediation technologies. Mine-waste samples consisted of oxidized and unoxidized sulfidic ore and waste rock, and flotation-mill tailings. These samples contained as much as 16 weight percent sulfides that included chalcopyrite, pyrite, pyrrhotite, and sphalerite. During oxidation, sulfides weather and may release potentially toxic trace elements and may produce acid. In addition, soluble efflorescent sulfate salts were identified at the mines; during rain events, the dissolution of these salts contributes acid and metals to receiving waters. Mine waste contained concentrations of cadmium, copper, and iron that exceeded USEPA Preliminary Remediation Goals. The concentrations of selenium in mine waste were higher than the average composition of eastern United States soils. Most mine waste was

  8. Discussion on Acidic Mining Drainage Production and Prevention in Carbonate Rock Area%碳酸盐岩地区矿山酸性排水的产生及其防治初探

    罗远红; 雷良奇; 常耀辉; 马于涛

    2011-01-01

    The sulphide in tailings produces acidic mining drainage(AMD) after a series of physical and chemical reactions with air,water,microorganisms.People once have considered that the tailings in carbonate rock areas will not cause acid pollutions because the carbonate minerals in tailings and surrounding rocks have neutralization effect.But there are serious acid pollutions in typical carbonate rock areas like Dachang of Guangxi province,Fankou and Dabaoshan of Guangdong province,Niujiaotang of Guizhou province,etc.The main cause is that in the process of carbonate mineral neutralization,the secondary minerals precipitate and adhere to the surface of carbonate minerals and stop further response,so the actual neutralization dose can not meet the theoretical value.Acidic mining drainage carries large amounts of metal ions which could bring serious damage to ecological environment and mine engineering facilities in carbonate rock areas.According to the characteristics of tailings in carbonate rock areas,the most efficient method for acidification of tailings is to adopt covering method for new tailings and permeable reactive barriers for acidified tailings.%尾矿中的硫化物在空气、水、微生物等的作用下,发生一系列的物理化学反应,形成矿山酸性排水(AMD)。在碳酸盐岩地区,由于尾矿和围岩中都含有大量对酸具有中和效应的碳酸盐矿物,于是人们一直认为碳酸盐岩地区的尾矿不存在酸污染。而如广西大厂、广东凡口及大宝山、贵州牛角塘等碳酸盐岩地区矿山的尾矿却存在着严重的酸污染,其主要原因是碳酸盐矿物在中和酸水过程中,表面会形成阻止反应进一步进行的次生包壳,碳酸盐矿物的实际中和量达不到其理论值。矿山酸性排水携带大量的重金属离子,对碳酸盐岩地区的生态环境及矿山工程设施带来严重的危害。针对碳酸盐岩地区尾矿自身的特殊性,对新建尾矿堆采用覆盖

  9. Permeable reactive barriers for the treatment of mine tailings drainage water

    Laboratory tests and field-scale demonstrations indicate that permeable reactive barriers have the potential to prevent the discharge of acidic, metal-rich, waters from mine wastes. Reactive barriers designed to induced bacterially mediated sulfate reduction have been used to promote the precipitation of sparingly soluble sulfide minerals. These reactions result in the attenuation of dissolved metals, including Fe, Ni, Zn, Cd, Co and Cu. Laboratory batch and column studies, conducted under conditions that are similar to those typically observed in aquifers affected by mine drainage water, indicate that sulfate reduction and metal-sulfide precipitation mechanisms result in decreases in the concentrations of sulfate iron and other metals. In the column experiments, sulfate and iron were removed from synthetic mine drainage water at rates of 500-800 mmol day-1 m3. In a pilot-scale field study, test cells installed into an aquifer containing a plume of mine waste-impacted groundwater, induced sulfate reduction and metal-sulfide precipitation. Within a flow path of less than one meter, sulfate reduction and metal sulfide precipitation reactions resulted in the removal of iron and production of alkalinity to the extent that the acid generating potential of the plume water was removed. A full-scale permeable reactive barrier was installed at the same site in August 1995. Comparing water entering the barrier to treated water existing the barrier, sulfate concentrations decrease from 2,400-4,500 mg/L to 200-3,600 mg/L and Fe concentrations decrease from 250-1,300 mg/L to 1.0-40 mg/L. After passing through the reactive barrier, groundwater is transformed from acid producing to acid consuming. (orig.)

  10. Application of water flow and geochemical models to support the remediation of acid rock drainage from the uranium mining site of Pocos de Caldas, Brazil

    Available in abstract form only. Full text of publication follows: This paper discusses the use of two numerical models (HYDRUS-2D and STEADQL-v4) for simulating water flow and relevant geochemical processes in one of the waste rock piles of the first uranium mine in Brazil, in order to facilitate the selection of appropriate remediation strategies. The long time scale required for the oxidation of sulfidic wastes (at least 600 years) implies the need to implement permanent remediation actions. The best remediation scheme should depend on the water flow regime inside the waste pile and on the geochemical processes that occur as a result of the interactions between water and the waste (especially oxidative dissolution of pyrite). Accurate modeling of the waste site, which contains a wide range of grain and rock sizes at different degrees of water saturation and is subject to reactive multicomponent transport, entails considerable physical, mathematical and numerical challenges. This paper describes the approach used to obtain a detailed representation of the system involving both unsaturated/ saturated flow (most of the physical properties of the waste were estimated from measured data) and the geochemical network reactions (including equilibrium and kinetics reactions). (authors)

  11. Analysis of Microbial Community Composition in Obturating Acid Mine Drainage%封闭环境下酸性矿坑水中微生物生态多样性的研究

    霍强; 刘晰; 刘文斌; 谢建平; 刘新星

    2009-01-01

    Tong Lushan Copper Mine has the longest exploitation time span in the world. Many disused mines produce a large amount of environmental detrimental acid mine drainage (AMD). The microbial community in obturating AMD samples,which collected from Tong Lushan Copper Mine,was identified by the technology of the restriction fragment length polymorphisma (RFLP) analysis of bacterial and archaeal 16S rDNA clone libraries. The bacterial and archaeal richness of acidophilic communities in this acidic and high-ion-concentration AMD were lower when compared with other extremophile and non-extremophile assemblages. The result of RFLP analysis and phylogenetic anlysis show that the majority of the bacterial clones were A. ferrooxidans belonging to the gamma-Proteobacteria and L. ferrooxidans belonging to the Nitospira while the majority of the archaeal clones were affiliated with Thermoplasma.Archaeal clones related to uncultured methanogenic archaeon were first found in obturating AMD environment and accounted for more than a quarter of the total archaeal clones. This microbial community structure composed by both bacteria and archaea contributed much to the generation of AMD.%铜绿山铜矿是世界开采时间最长的矿井之一,在开采过程中有许多矿井被废弃,许多废弃的矿井内产生了大量的对环境有害的酸性矿坑水.酸性矿坑水取自铜绿山铜矿某废弃矿井,利用限制性酶切片断多样性分析(RFLP分析)对酸性矿坑水中的微生物生态多样性进行了研究.研究表明,酸性矿坑水呈酸性,相对于其他极端与非极端生态环境,酸性矿坑水中的细菌与古菌的群落多样性较低.RFLP分析与系统发育分析表明,酸性矿坑水中细菌主要由A.fcrrooxidans(属于gamma-Proteobacteria)和L.ferrooxidans(属于Nitospira)成;古菌主要由Thermoplasma相关古菌组成.在这种封闭环境的酸性矿坑水中首次发现了类似于产甲烷古菌的克隆片断,其占古菌种群的四分

  12. The treatment possibility of mining drainage from horizon 830 in the Sasa Mine, Macedonia

    Golomeova, Mirjana; Stojanovska, Marija; Krstev, Boris; Golomeov, Blagoj; Zendelska, Afrodita; Krstev, Aleksandar

    2013-01-01

    The drainage system on mining area Sasa consists of surface water from the rivers Crvena, Svinja and Kozja which are flowing from field of ore deposit, and with other small mountain tributaries that flow into the River Kamenichka. The results of the measurements show that in all samples from surface waters are detected increased concentrations of heavy and toxic metals, except for the water of the River Crvena. These increased concentrations are a consequence of historical anthropoge...

  13. Geochemistry and stable sulfur and oxygen isotope ratios of the Podwisniowka pit pond water generated by acid mine drainage (Holy Cross Mountains, south-central Poland)

    The paper presents the results of a geochemical and isotopic study of acidic pond water in the abandoned Podwisniowka quarry (Poland). The scope of investigations also encompassed mineralogical and isotopic studies of pyrite and related supergene minerals. Compared to similar sites throughout the world, the pit pond water examined is characterized by a very low pH averaging 2.64 ± 0.33 and simultaneously very low concentrations of SO42- (geometric mean of 237 ± 57 mg L-1), Fe(II) (4.8 ± 3.4 mg L-1), Fe(III) (10.0 ± 6.2 mg L-1) and other trace elements. This acidity has been generated by complex processes of As-rich pyrite oxidation combined primarily with hydrolysis, precipitation, and transformation of Fe oxyhydroxysulfates and oxyhydroxides into goethite. The specific mineralogy of ore and gangue minerals, but especially the lack of acid-buffering constituents, has additionally contributed to the very low pH and element concentrations. Of the toxic elements, the high content of As (1111-1879 mg kg-1) in the western part of pit pond sediment may be of great concern, especially when using lime as a neutralizing agent of the acidic water. The δ34S of soluble SO4 varied from -19.8 per mille to -11.1 per mille and was different from that of efflorescent sulfates (-25.7 per mille to -25.4 per mille ) and host pyrite (-25.4 ± 2.5 per mille ). The comparison of the δ18O-SO42- (-2.0 ± 1.2 per mille ) and δ18O-H2O (-6.2 ± 3.5 per mille ) values indicated that the pyrite underwent bacterially catalyzed oxidation by two natural oxidants, primarily by Fe3+ and to a lesser extent O2

  14. Application of maghemite nanoparticles as sorbents for the removal of Cu(II), Mn(II) and U(VI) ions from aqueous solution in acid mine drainage conditions

    Etale, Anita; Tutu, Hlanganani; Drake, Deanne C.

    2014-06-01

    The adsorptive removal of Cu(II), Mn(II) and U(VI) by maghemite nanoparticles (NPs) was investigated under acid mine drainage (AMD) conditions to assess NP potential for remediating AMD-contaminated water. The effects of time, NP and metal concentration, as well as manganese and sulphate ions were quantified at pH 3. Adsorption of all three ions was rapid, and equilibrium was attained in 5 min or less. 56 % of Cu, 53 % of Mn and 49 % of U were adsorbed. In addition, adsorption efficiencies were enhanced by ≥10 % in the presence of manganese and sulphate ions, although Cu sorption was reduced in 1:2 Cu-to-Mn solutions. Adsorption also increased with pH: 86 % Cu, 62 % Mn and 77 % U were removed from solution at pH 9 and increasing initial metal concentrations. Increasing NP concentrations did not, however, always increase metal removal. Kinetics data were best described by a pseudo-second-order model, implying chemisorption, while isotherm data were better fitted by the Freundlich model. Metal removal by NPs was then tested in AMD-contaminated surface and ground water. Removal efficiencies of up to 46 % for Cu and 54 % for Mn in surface water and 8 % for Cu and 50 % for Mn in ground water were achieved, confirming that maghemite NPs can be applied for the removal of these ions from AMD-contaminated waters. Notably, whereas sulphates may increase adsorption efficiencies, high Mn concentrations in AMD will likely inhibit Cu sorption.

  15. Application of maghemite nanoparticles as sorbents for the removal of Cu(II), Mn(II) and U(VI) ions from aqueous solution in acid mine drainage conditions

    Etale, Anita; Tutu, Hlanganani; Drake, Deanne C.

    2016-06-01

    The adsorptive removal of Cu(II), Mn(II) and U(VI) by maghemite nanoparticles (NPs) was investigated under acid mine drainage (AMD) conditions to assess NP potential for remediating AMD-contaminated water. The effects of time, NP and metal concentration, as well as manganese and sulphate ions were quantified at pH 3. Adsorption of all three ions was rapid, and equilibrium was attained in 5 min or less. 56 % of Cu, 53 % of Mn and 49 % of U were adsorbed. In addition, adsorption efficiencies were enhanced by ≥10 % in the presence of manganese and sulphate ions, although Cu sorption was reduced in 1:2 Cu-to-Mn solutions. Adsorption also increased with pH: 86 % Cu, 62 % Mn and 77 % U were removed from solution at pH 9 and increasing initial metal concentrations. Increasing NP concentrations did not, however, always increase metal removal. Kinetics data were best described by a pseudo-second-order model, implying chemisorption, while isotherm data were better fitted by the Freundlich model. Metal removal by NPs was then tested in AMD-contaminated surface and ground water. Removal efficiencies of up to 46 % for Cu and 54 % for Mn in surface water and 8 % for Cu and 50 % for Mn in ground water were achieved, confirming that maghemite NPs can be applied for the removal of these ions from AMD-contaminated waters. Notably, whereas sulphates may increase adsorption efficiencies, high Mn concentrations in AMD will likely inhibit Cu sorption.

  16. The Metal And Sulphate Removal From Mine Drainage Waters By Biological-Chemical Ways

    Jenčárová Jana; Luptáková Alena

    2015-01-01

    Mine drainage waters are often characterized by high concentrations of sulphates and metals as a consequence of the mining industry of sulphide minerals. The aims of this work are to prove some biological-chemical processes utilization for the mine drainage water treatment. The studied principles of contamination elimination from these waters include sulphate reduction and metal bioprecipitation by the application of sulphate-reducing bacteria (SRB). Other studied process was metal sorption b...

  17. Wetlands as a means to reduce the environmental impact of mine drainage waters

    Sjöblom, Åsa

    2003-01-01

    In many mining regions of the world, pollution of surface water and groundwater by drainage water originating from mines aiming waste poses either a serious threat to the environment, or a severe environmental problem. During the last two and a half decades, treatment of mine drainage water in constructed and natural wetlands has emerged as an alternative to more conventional methods to handle the problem. In this thesis, the major biogeochemical processes behind metal immobilization in wetla...

  18. Geochemistry and stable sulfur and oxygen isotope ratios of the Podwisniowka pit pond water generated by acid mine drainage (Holy Cross Mountains, south-central Poland)

    Migaszewski, Zdzislaw M. [Jan Kochanowski University (Pedagogical University), Institute of Chemistry, Geochemistry and the Environment Division, 15G Swietokrzyska Street, 25-406 Kielce (Poland)], E-mail: zmig@ujk.kielce.pl; Galuszka, Agnieszka [Jan Kochanowski University (Pedagogical University), Institute of Chemistry, Geochemistry and the Environment Division, 15G Swietokrzyska Street, 25-406 Kielce (Poland); Halas, Stanislaw [Maria Curie-Sklodowska University, Institute of Physics, Mass Spectrometry Laboratory, 1 Maria Curie-Sklodowska Square, 20-031 Lublin (Poland); Dolegowska, Sabina [Jan Kochanowski University (Pedagogical University), Institute of Chemistry, Geochemistry and the Environment Division, 15G Swietokrzyska Street, 25-406 Kielce (Poland); Dabek, Jozef [Maria Curie-Sklodowska University, Institute of Physics, Mass Spectrometry Laboratory, 1 Maria Curie-Sklodowska Square, 20-031 Lublin (Poland); Starnawska, Ewa [Electron Microscope Laboratory, Polish Geological Institute, 4 Rakowiecka Street, 00-975 Warsaw (Poland)

    2008-12-15

    The paper presents the results of a geochemical and isotopic study of acidic pond water in the abandoned Podwisniowka quarry (Poland). The scope of investigations also encompassed mineralogical and isotopic studies of pyrite and related supergene minerals. Compared to similar sites throughout the world, the pit pond water examined is characterized by a very low pH averaging 2.64 {+-} 0.33 and simultaneously very low concentrations of SO{sub 4}{sup 2-} (geometric mean of 237 {+-} 57 mg L{sup -1}), Fe(II) (4.8 {+-} 3.4 mg L{sup -1}), Fe(III) (10.0 {+-} 6.2 mg L{sup -1}) and other trace elements. This acidity has been generated by complex processes of As-rich pyrite oxidation combined primarily with hydrolysis, precipitation, and transformation of Fe oxyhydroxysulfates and oxyhydroxides into goethite. The specific mineralogy of ore and gangue minerals, but especially the lack of acid-buffering constituents, has additionally contributed to the very low pH and element concentrations. Of the toxic elements, the high content of As (1111-1879 mg kg{sup -1}) in the western part of pit pond sediment may be of great concern, especially when using lime as a neutralizing agent of the acidic water. The {delta}{sup 34}S of soluble SO{sub 4} varied from -19.8 per mille to -11.1 per mille and was different from that of efflorescent sulfates (-25.7 per mille to -25.4 per mille ) and host pyrite (-25.4 {+-} 2.5 per mille ). The comparison of the {delta}{sup 18}O-SO{sub 4}{sup 2-} (-2.0 {+-} 1.2 per mille ) and {delta}{sup 18}O-H{sub 2}O (-6.2 {+-} 3.5 per mille ) values indicated that the pyrite underwent bacterially catalyzed oxidation by two natural oxidants, primarily by Fe{sup 3+} and to a lesser extent O{sub 2}.

  19. Appropriate reactive mixtures of organic wastes for the treatment of mine drainage in Korea

    A sustainable solution to the problem of mine water pollution is the use of passive bioreactors. A few passive systems (including first generation bioreactors) installed in South Korea, demonstrated limited efficiency of mushroom compost as a sole substrate. This paper presented a study that used five natural organic materials in order to select a better replacement substrate. The five organic materials involved in the study were cow manure; cut rice straw; wood chips; sawdust; and mushroom compost. The compounds were characterized and tested, alone and in mixtures in batch bioreactors over a 35-day period for the treatment of circumneutral and acidic mine drainage. The paper discussed the material and methods, including synthetic mine drainage preparation; characterization of organic and inorganic material; laboratory scale batch bioreactor operation; and sampling and analysis. It was concluded that overall, mixtures of organic and cellulosic waste showed better performance than mushroom compost in term of pH neutralizing and heavy metal removal in 35 days of batch testing. 15 refs., 1 tab., 3 figs.

  20. Acid rock drainage and climate change

    Nordstrom, D.K.

    2009-01-01

    Rainfall events cause both increases and decreases in acid and metals concentrations and their loadings from mine wastes, and unmined mineralized areas, into receiving streams based on data from 3 mines sites in the United States and other sites outside the US. Gradual increases in concentrations occur during long dry spells and sudden large increases are observed during the rising limb of the discharge following dry spells (first flush). By the time the discharge peak has occurred, concentrations are usually decreased, often to levels below those of pre-storm conditions and then they slowly rise again during the next dry spell. These dynamic changes in concentrations and loadings are related to the dissolution of soluble salts and the flushing out of waters that were concentrated by evaporation. The underlying processes, pyrite oxidation and host rock dissolution, do not end until the pyrite is fully weathered, which can take hundreds to thousands of years. These observations can be generalized to predict future conditions caused by droughts related to El Ni??o and climate change associated with global warming. Already, the time period for dry summers is lengthening in the western US and rainstorms are further apart and more intense when they happen. Consequently, flushing of inactive or active mine sites and mineralized but unmined sites will cause larger sudden increases in concentrations that will be an ever increasing danger to aquatic life with climate change. Higher average concentrations will be observed during longer low-flow periods. Remediation efforts will have to increase the capacity of engineered designs to deal with more extreme conditions, not average conditions of previous years.

  1. Sustainable Remediation of Legacy Mine Drainage: A Case Study of the Flight 93 National Memorial

    Emili, Lisa A.; Pizarchik, Joseph; Mahan, Carolyn G.

    2016-03-01

    Pollution from mining activities is a global environmental concern, not limited to areas of current resource extraction, but including a broader geographic area of historic (legacy) and abandoned mines. The pollution of surface waters from acid mine drainage is a persistent problem and requires a holistic and sustainable approach to addressing the spatial and temporal complexity of mining-specific problems. In this paper, we focus on the environmental, socio-economic, and legal challenges associated with the concurrent activities to remediate a coal mine site and to develop a national memorial following a catastrophic event. We provide a conceptual construct of a socio-ecological system defined at several spatial, temporal, and organizational scales and a critical synthesis of the technical and social learning processes necessary to achieving sustainable environmental remediation. Our case study is an example of a multi-disciplinary management approach, whereby collaborative interaction of stakeholders, the emergence of functional linkages for information exchange, and mediation led to scientifically informed decision making, creative management solutions, and ultimately environmental policy change.

  2. Sustainable Remediation of Legacy Mine Drainage: A Case Study of the Flight 93 National Memorial.

    Emili, Lisa A; Pizarchik, Joseph; Mahan, Carolyn G

    2016-03-01

    Pollution from mining activities is a global environmental concern, not limited to areas of current resource extraction, but including a broader geographic area of historic (legacy) and abandoned mines. The pollution of surface waters from acid mine drainage is a persistent problem and requires a holistic and sustainable approach to addressing the spatial and temporal complexity of mining-specific problems. In this paper, we focus on the environmental, socio-economic, and legal challenges associated with the concurrent activities to remediate a coal mine site and to develop a national memorial following a catastrophic event. We provide a conceptual construct of a socio-ecological system defined at several spatial, temporal, and organizational scales and a critical synthesis of the technical and social learning processes necessary to achieving sustainable environmental remediation. Our case study is an example of a multi-disciplinary management approach, whereby collaborative interaction of stakeholders, the emergence of functional linkages for information exchange, and mediation led to scientifically informed decision making, creative management solutions, and ultimately environmental policy change. PMID:26440656

  3. Oxycline formation induced by Fe(II) oxidation in a water reservoir affected by acid mine drainage modeled using a 2D hydrodynamic and water quality model - CE-QUAL-W2.

    Torres, Ester; Galván, Laura; Cánovas, Carlos Ruiz; Soria-Píriz, Sara; Arbat-Bofill, Marina; Nardi, Albert; Papaspyrou, Sokratis; Ayora, Carlos

    2016-08-15

    The Sancho reservoir is an acid mine drainage (AMD)-contaminated reservoir located in the Huelva province (SW Spain) with a pH close to 3.5. The water is only used for a refrigeration system of a paper mill. The Sancho reservoir is holomictic with one mixing period per year in the winter. During this mixing period, oxygenated water reaches the sediment, while under stratified conditions (the rest of the year) hypoxic conditions develop at the hypolimnion. A CE-QUAL-W2 model was calibrated for the Sancho Reservoir to predict the thermocline and oxycline formation, as well as the salinity, ammonium, nitrate, phosphorous, algal, chlorophyll-a, and iron concentrations. The version 3.7 of the model does not allow simulating the oxidation of Fe(II) in the water column, which limits the oxygen consumption of the organic matter oxidation. However, to evaluate the impact of Fe(II) oxidation on the oxycline formation, Fe(II) has been introduced into the model based on its relationship with labile dissolved organic matter (LDOM). The results show that Fe oxidation is the main factor responsible for the oxygen depletion in the hypolimnion of the Sancho Reservoir. The limiting factors for green algal growth have also been studied. The model predicted that ammonium, nitrate, and phosphate were not limiting factors for green algal growth. Light appeared to be one of the limiting factors for algal growth, while chlorophyll-a and dissolved oxygen concentrations could not be fully described. We hypothesize that dissolved CO2 is one of the limiting nutrients due to losses by the high acidity of the water column. The sensitivity tests carried out support this hypothesis. Two different remediation scenarios have been tested with the calibrated model: 1) an AMD passive treatment plant installed at the river, which removes completely Fe, and 2) different depth water extractions. If no Fe was introduced into the reservoir, water quality would significantly improve in only two years

  4. DESIGN JUSTIFICATION DRAINAGE PROTECTION AT ELEVATED GROUNDWATER LEVELS GROUNDWATER DUE TO INFILTRATION MINE WATERS

    Ishtchenko A. V.

    2015-12-01

    Full Text Available The article presents the design study for construction of a drainage system on the territory of gardening association «Zarya» in the region of Gukovo in Krasnosulinsky district of Rostov region. Construction of a drainage system is a prerequisite for reducing the groundwater level caused by the infiltration of the drainage complex mine called Burgustinskaya. The results of the calculations determined the value of the total infiltration groundwater feeding; inflow rate to each of the 6 drains per unit length, water flow ability of a horizontal pipe drainage, as well as a diameter of drainage pipes

  5. DESIGN JUSTIFICATION DRAINAGE PROTECTION AT ELEVATED GROUNDWATER LEVELS GROUNDWATER DUE TO INFILTRATION MINE WATERS

    Ishtchenko A. V.; Kosichenko Y. M.; Baev O. A.

    2015-01-01

    The article presents the design study for construction of a drainage system on the territory of gardening association «Zarya» in the region of Gukovo in Krasnosulinsky district of Rostov region. Construction of a drainage system is a prerequisite for reducing the groundwater level caused by the infiltration of the drainage complex mine called Burgustinskaya. The results of the calculations determined the value of the total infiltration groundwater feeding; inflow rate to each of the 6 drains ...

  6. Characterization of the core microbiota of the drainage and surrounding soil of a Brazilian copper mine

    Letícia Bianca Pereira; Renato Vicentini; Laura M. M. Ottoboni

    2015-01-01

    Abstract The core microbiota of a neutral mine drainage and the surrounding high heavy metal content soil at a Brazilian copper mine were characterized by 16S rDNA pyrosequencing. The core microbiota of the drainage was dominated by the generalist genus Meiothermus. The soil samples contained a more heterogeneous bacterial community, with the presence of both generalist and specialist bacteria. Both environments supported mainly heterotrophic bacteria, including organisms resistant to heavy m...

  7. Colloid-borne uranium and other heavy metals in the water of a mine drainage gallery

    The water of a mine drainage gallery was investigated for its contents of colloid-borne heavy metals with emphasis on uranium. About 1 mg/L of colloid particles of 100 to 300 nm were found. They consist of a matrix of Fe and Al oxyhydroxides and are formed when anoxic slightly acidic shaft waters mix with oxic near-neutral gallery water. The colloid particles bear toxic trace elements such as As, Pb, and Cu. Almost 100% of the As and Pb and about 70% of the Cu contained in the water are colloid-borne. Carbonato complexes prevent the uranyl from being adsorbed on the colloids in the unaltered gallery water. Acidification destroys these complexes: up to 50% of the uranium is attached to the colloids in the slightly acidic pH region. Further acidification converts the uranyl again to a 'non-colloidal' form. (orig.)

  8. Low maintenance options and challenges for the collection and interception of mine drainage

    A vast majority of mining operations in the United Kingdom have been abandoned, leaving a legacy of abandoned deep coal and metal mines and waste rock piles. The United Kingdom has committed to address environmental problems from deep coal mines of the former nationalized coal mining industry. No such body for abandoned metal mines or for waste rock piles exists, therefore remediation initiatives tend to be in stages. This presentation described low maintenance options and challenges for the collection and interception of mine drainage. The presentation provided several illustrations and charts as well as discussions related to regional dewatering; aquifer protection; pump-and-treat; and gravity drainage with treatment. Several challenges such as water quality, conservation, archaeology, local interest, and health and safety were also presented. It was demonstrated that for a variety of reasons, most current mine water treatment systems in the United Kingdom comprise pumping to a treatment system, or even pumping to avoid treatment. tabs., figs

  9. Uso de entulho de construção civil como sistema de cobertura para abatimento de drenagem ácida de mina em uma mina abandonada de pirita Use of solid residues from civil construction as a covering system for acid mine drainage abatement in an abandoned pyrite mine

    Natália Cristiane de Moraes

    2011-06-01

    leaching columns, to assess the acid mine drainage potential in samples collected from the mine site and to evaluate the possibility of controlling and minimizing acid generation by using solid residues as a covering system. Laboratory results show that cover with solid residues of civil construction was effective in the reducing the acidity, concentration of metals and sulfate.

  10. Microbial exoenzymes as bioindicators of acid rock drainage impacts in the Finniss River

    Sediment samples were collected from several sites along the East Branch of the Finniss River during the dry season (June, 1999), when the East Branch is drying into a series of ponds. The sites included those upstream from the Rum Jungle mine site (EB8A, EB8B, FCA, FCB), a site receiving acid leachate from the waste rock (WO), sites downstream from the mine that are impacted by acid and metal contamination (EB6, TCP, EB5D, EB4U, EB2) and reference sites not subject to acid rock drainage (HS, EB4S, LFRB). Exoenzyme activities were measured with a spectrofluorometric technique that involved measuring the increase in fluorescence when an artificial fluorogenic substrate (that mimics the natural substrate) is hydrolysed to a highly fluorescent product. The present findings indicate that the acid rock drainage impacted sediments contain acidophilic, heterotrophic microorganisms, bacteria and/or fungi, producing extracellular enzymes adapted to the acid conditions. This study has demonstrated that measurements of extracellular enzyme activities in river sediments provide a rapid, sensitive technique for determining microbial activity and productivity. In aquatic ecosystems some exoenzymes, particularly leucine-aminopeptidase, could be used as bioindicators of pollution from acid rock drainage

  11. Spatial variations in water composition at a northern Canadian lake impacted by mine drainage

    Release of acid drainage from mine-waste disposal areas is a problem of international scale. Contaminated surface water, derived from mine wastes, originates both as direct surface runoff and, indirectly, as subsurface groundwater flow. At Camp Lake, a small Canadian Shield lake that is in northern Manitoba and is ice-covered 6 months of the year, direct and indirect release of drainage from an adjacent sulfide-rich tailings impoundment has severely affected the quality of the lake water. Concentrations of the products from sulfide oxidation are extremely high in the pore waters of the tailings impoundment. Groundwater and surface water derived from the impoundment discharge into a semi-isolated shallow bay in Camp Lake. The incorporation of this aqueous effluent has altered the composition of the lake water, which in turn has modified the physical limnology of the lake. Geochemical profiles of the water column indicate that, despite its shallow depth (6 m), the bay is stratified throughout the year. The greatest accumulation of dissolved metals and SO4 is in the lower portion of the water column, with concentrations up to 8500 mg L-1 Fe, 20,000 mg L-1 SO4, 30 mg L-1 Zn, 100 mg L-1 Al, and elevated concentrations of Cu, Cd, Pb and Ni. Meromictic conditions and very high solute concentrations are limited to the bay. Outside the bay, solute concentrations are lower and some stratification of the water column exists. Identification of locations and composition of groundwater discharge relative to lake bathymetry is a fundamental aspect of understanding chemical evolution and physical stability of mine-impacted lakes

  12. The Metal And Sulphate Removal From Mine Drainage Waters By Biological-Chemical Ways

    Jenčárová Jana

    2015-06-01

    Full Text Available Mine drainage waters are often characterized by high concentrations of sulphates and metals as a consequence of the mining industry of sulphide minerals. The aims of this work are to prove some biological-chemical processes utilization for the mine drainage water treatment. The studied principles of contamination elimination from these waters include sulphate reduction and metal bioprecipitation by the application of sulphate-reducing bacteria (SRB. Other studied process was metal sorption by prepared biogenic sorbent. Mine drainage waters from Slovak localities Banská Štiavnica and Smolník were used to the pollution removal examination. In Banská Štiavnica water, sulphates decreased below the legislative limit. The elimination of zinc by sorption experiments achieved 84 % and 65 %, respectively.

  13. Corrosion control when using passively treated abandoned mine drainage as alternative makeup water for cooling systems.

    Hsieh, Ming-Kai; Chien, Shih-Hsiang; Li, Heng; Monnell, Jason D; Dzombak, David A; Vidic, Radisav D

    2011-09-01

    Passively treated abandoned mine drainage (AMD) is a promising alternative to fresh water as power plant cooling water system makeup water in mining regions where such water is abundant. Passive treatment and reuse of AMD can avoid the contamination of surface water caused by discharge of abandoned mine water, which typically is acidic and contains high concentrations of metals, especially iron. The purpose of this study was to evaluate the feasibility of reusing passively treated AMD in cooling systems with respect to corrosion control through laboratory experiments and pilot-scale field testing. The results showed that, with the addition of the inhibitor mixture orthophosphate and tolyltriazole, mild steel and copper corrosion rates were reduced to acceptable levels (< 0.127 mm/y and < 0.0076 mm/y, respectively). Aluminum had pitting corrosion problems in every condition tested, while cupronickel showed that, even in the absence of any inhibitor and in the presence of the biocide monochloramine, its corrosion rate was still very low (0.018 mm/y). PMID:22073728

  14. Isotopic evidence of enhanced carbonate dissolution at a coal mine drainage site in Allegheny County, Pennsylvania, USA

    Highlights: ► Coal mine discharge. ► Carbon, sulfur, oxygen and strontium isotopes track sources of carbon. ► Enhanced carbonate weathering due to sulfuric acid-enhanced dissolution and cation exchange. ► Carbon dioxide outgassing. - Abstract: Stable isotopes were used to determine the sources and fate of dissolved inorganic C (DIC) in the circumneutral pH drainage from an abandoned bituminous coal mine in western Pennsylvania. The C isotope signatures of DIC (δ13CDIC) were intermediate between local carbonate and organic C sources, but were higher than those of contemporaneous Pennsylvanian age groundwaters in the region. This suggests a significant contribution of C enriched in 13C due to enhanced carbonate dissolution associated with the release of H2SO4 from pyrite oxidation. The Sr isotopic signature of the drainage was similar to other regional mine waters associated with the same coal seam and reflected contributions from limestone dissolution and cation exchange with clay minerals. The relatively high δ34SSO4 and δ18OSO4 isotopic signatures of the mine drainage and the presence of presumptive SO4-reducing bacteria suggest that SO4 reduction activity also contributes C depleted in 13C isotope to the total DIC pool. With distance downstream from the mine portal, C isotope signatures in the drainage increased, accompanied by decreased total DIC concentrations and increased pH. These data are consistent with H2SO4 dissolution of carbonate rocks, enhanced by cation exchange, and C release to the atmosphere via CO2 outgassing

  15. The impact of episodic coal mine drainage pollution on benthic macroinvertebrates in streams in the Anthracite region of Pennsylvania

    Episodic coal mine drainage, caused by fluctuations in mine discharges relative to stream flow, has devastating effects on aquatic macroinvertebrate communities. Seven stream reaches in the Anthracite region of Pennsylvania were identified as chronically, episodically or not impaired by mine drainage, and sampled seasonally for 1 year to determine the effect of episodic mine drainage on macroinvertebrates. Specific conductance fluctuated seasonally in episodic sites; it was lower in winter when discharge increased and higher in summer when discharges decreased and mine drainage made up a larger proportion of stream flow. Although we hypothesized that episodic streams would have higher macroinvertebrate richness than chronic streams, comparisons showed no differences in richness between treatments. Episodic pollution may result from undersized or poorly maintained passive treatment systems; therefore, intensive macroinvertebrate monitoring may be needed to identify streams being affected by episodic mine drainage because macroinvertebrate richness may be sensitive to water quality fluctuations. - Episodic coal mine pollution decreases benthic macroinvertebrate richness and density

  16. Observations and assessment of iron oxide nanoparticles in metal-polluted mine drainage within a steep redox gradient, and a comparison to synthetic analogs

    Johnson, Carol A.

    2014-01-01

    The complex interactions at the interfaces of minerals, microbes, and metals drive the cycling of iron and the fate and transport of metal(loid)s in contaminated systems. The former uranium mine near Ronneburg, Germany is one such system, where slightly acidic mine drainage crossing a steep redox gradient (groundwater outflow into a stream) forms and transforms iron (oxy)hydroxide nanoparticles. These particles interact with toxic metal(loid)s in water and sediments. Iron oxidizing and reduci...

  17. Reduction of acid rock drainage using steel slag in cover systems over sulfide rock waste piles.

    de Almeida, Rodrigo Pereira; Leite, Adilson do Lago; Borghetti Soares, Anderson

    2015-04-01

    The extraction of gold, coal, nickel, uranium, copper and other earth-moving activities almost always leads to environmental damage. In metal and coal extraction, exposure of sulfide minerals to the atmosphere leads to generation of acid rock drainage (ARD) and in underground mining to acid mine drainage (AMD) due to contamination of infiltrating groundwater. This study proposes to develop a reactive cover system that inhibits infiltration of oxygen and also releases alkalinity to increase the pH of generated ARD and attenuate metal contaminants at the same time. The reactive cover system is constructed using steel slag, a waste product generated from steel industries. This study shows that this type of cover system has the potential to reduce some of the adverse effects of sulfide mine waste disposal on land. Geochemical and geotechnical characterization tests were carried out. Different proportions of sulfide mine waste and steel slag were studied in leachate extraction tests. The best proportion was 33% of steel slag in dry weight. Other tests were conducted as follows: soil consolidation, saturated permeability and soil water characteristic curve. The cover system was numerically modeled through unsaturated flux analysis using Vadose/w. The solution proposed is an oxygen transport barrier that allows rain water percolation to treat the ARD in the waste rock pile. The results showed that the waste pile slope is an important factor and the cover system must have 5 m thickness to achieve an acceptable effectiveness. PMID:25750056

  18. On the neutralization of acid rock drainage by carbonate and silicate minerals

    Sherlock, E. J.; Lawrence, R. W.; Poulin, R.

    1995-02-01

    The net result of acid-generating and-neutralizing reactions within mining wastes is termed acid rock drainage (ARD). The oxidation of sulfide minerals is the major contributor to acid generation. Dissolution and alteration of various minerals can contribute to the neutralization of acid. Definitions of alkalinity, acidity, and buffer capacity are reviewed, and a detailed discussion of the dissolution and neutralizing capacity of carbonate and silicate minerals related to equilibium conditions, dissolution mechanism, and kinetics is provided. Factors that determine neutralization rate by carbonate and silicate minerals include: pH, PCO 2, equilibrium conditions, temperature, mineral composition and structure, redox conditions, and the presence of “foreign” ions. Similar factors affect sulfide oxidation. Comparison of rates shows sulfides react fastest, followed by carbonates and silicates. The differences in the reaction mechanisms and kinetics of neutralization have important implications in the prediction, control, and regulation of ARD. Current static and kinetic prediction methods upon which mine permitting, ARD control, and mine closure plans are based do not consider sample mineralogy or the kinetics of the acid-generating and-neutralizing reactions. Erroneous test interpretations and predictions can result. The importance of considering mineralogy for site-specific interpretation is highlighted. Uncertainty in prediction leads to difficulties for the mine operator in developing satisfactory and cost-effective control and remediation measures. Thus, the application of regulations and guidelines for waste management planning need to beflexible.

  19. A natural attenuation of arsenic in drainage from an abandoned arsenic mine dump

    At the abandoned As mine in Nishinomaki, Japan, discharged water from the mining and waste dump area is acidic and rich in As. However, the As concentration in the drainage has been decreased to below the maximum contaminant level (0.01 mg/l for drinking water, Japan) without any artificial treatments before mixing with a tributary to populated areas. This implies that the As concentration in water from the waste dump area has been naturally attenuated. To elucidate the reaction mechanisms of the natural attenuation, analysis of water quality and characterization of the precipitates from the stream floor were performed by measuring pH, ORP and electric conductivity on-site, as well as X-ray diffraction, ICP-mass spectrometry and ion-chromatography. Selective extractions and mineral alteration experiments were also conducted to estimate the distribution of As in constituent phases of the precipitates and to understand the stability of As-bearing phases, respectively. The water contamination resulted from oxidation of sulfide minerals in the waste rocks, i.e., the oxidation of pyrite and realgar and subsequent release of Fe, SO4, As(V) and proton. The released Fe(II) transformed to Fe(III) by bacterial oxidation; schwertmannite then formed immediately. While the As concentrations in the stream were lowered nearly to background level downstream, those in the ochreous precipitates were up to several tens of mg/g. The As(V) was effectively removed by the formed schwertmannite and had been naturally attenuated. Although schwertmannite is metastable with respect to goethite, the experiments show that the transformation of schwertmannite to goethite may be retarded by the presence of absorbed As(V) in the structure. Therefore, the attenuation of As in the drainage and the retention of As by schwertmannite are expected to be maintained for the long term

  20. Exposure of insects and insectivorous birds to metals and other elements from abandoned mine tailings in three Summit County drainages, Colorado

    Custer, Christine M.; Yang, C.; Crock, J.G.; Shearn-Bochsler, V.; Smith, K.S.; Hageman, P.L.

    2009-01-01

    Concentrations of 31 metals, metalloids, and other elements were measured in insects and insectivorous bird tissues from three drainages with different geochemistry and mining histories in Summit Co., Colorado, in 2003, 2004, and 2005. In insect samples, all 25 elements that were analyzed in all years increased in both Snake and Deer Creeks in the mining impacted areas compared to areas above and below the mining impacted areas. This distribution of elements was predicted from known or expected sediment contamination resulting from abandoned mine tailings in those drainages. Element concentrations in avian liver tissues were in concordance with levels in insects, that is with concentrations higher in mid-drainage areas where mine tailings were present compared to both upstream and downstream locations; these differences were not always statistically different, however. The lack of statistically significant differences in liver tissues, except for a few elements, was due to relatively small sample sizes and because many of these elements are essential and therefore well regulated by the bird's homeostatic processes. Most elements were at background concentrations in avian liver tissue except for Pb which was elevated at mid-drainage sites to levels where ??-aminolevulinic acid dehydratase activity was inhibited at other mining sites in Colorado. Lead exposure, however, was not at toxic levels. Fecal samples were not a good indication of what elements birds ingested and were potentially exposed to. ?? Springer Science+Business Media B.V. 2008.

  1. Pre- and post-construction analysis of a wetland used for mine drainage control

    A 0.39 ha constructed wetland in Athens County, Ohio is being evaluated for its ability to remove contaminants from acidic mine drainage. The wetland receives water flow from Lick run stream which is contaminated by two major abandoned underground mine seeps. The wetland effluent is then directed back into Lick Run, a tributary of the Hocking River. Data were collected 1.5 years prior to construction and 11 months following completion of the passive wetland system. Preconstruction data reported average spring quarter 1991 and 1992 iron concentrations in the stream at the future wetland influent and effluents sites to be 330 and 106 mg/l, while spring quarter 1993 showed iron levels at the wetland influent and effluent to be 64 and 3 mg/l, respectively. Iron removal percentages were 68% prior to the construction of the wetland and 95% following its completion. Preconstruction data were analyzed using a dynamic computer model and preliminary comparison with the first 11 months of the wetland data show the actual iron removal rates to be 4 g/m2 day1 compared to the predicted value of 6.5 g/m2 day1 (based on data collected from April 1991--March 1992, under similar hydrologic conditions)

  2. Use of EDTA in modified kinetic testing for contaminated drainage prediction from waste rocks: case of the Lac Tio mine.

    Plante, Benoît; Benzaazoua, Mostafa; Bussière, Bruno; Kandji, El-Hadji-Babacar; Chopard, Aurélie; Bouzahzah, Hassan

    2015-05-01

    The tools developed for acid mine drainage (AMD) prediction were proven unsuccessful to predict the geochemical behavior of mine waste rocks having a significant chemical sorption capacity, which delays the onset of contaminated neutral drainage (CND). The present work was performed in order to test a new approach of water quality prediction, by using a chelating agent solution (0.03 M EDTA, or ethylenediaminetetraacetic acid) in kinetic testing used for the prediction of the geochemical behavior of geologic material. The hypothesis underlying the proposed approach is that the EDTA solution should chelate the metals as soon as they are released by sulfide oxidation, inhibiting their sorption or secondary precipitation, and therefore reproduce a worst-case scenario where very low metal attenuation mechanisms are present in the drainage waters. Fresh and weathered waste rocks from the Lac Tio mine (Rio tinto, Iron and Titanium), which are known to generate Ni-CND at the field scale, were submitted to small-scale humidity cells in control tests (using deionized water) and using an EDTA solution. Results show that EDTA effectively prevents the metals to be sorbed or to precipitate as secondary minerals, therefore enabling to bypass the delay associated with metal sorption in the prediction of water quality from these materials. This work shows that the use of a chelating agent solution is a promising novel approach of water quality prediction and provides general guidelines to be used in further studies, which will help both practitioners and regulators to plan more efficient management and disposal strategies of mine wastes. PMID:25604563

  3. Variation in gas drainage rate from a coal seam during mining

    Li; Gang; Qi; Qingxin; Li; Hongyan; Fan; Xisheng

    2012-01-01

    Gas flow patterns during draining of gas from a coal seam during mining are discussed.The coal seam is treated as a dual medium with both pores and cracks.The seepage,diffusion,and desorption processes are treated using a gas flow equation that describes flow around drill holes.MATLAB is used to solve the differential equations.The permeability tracer test results from a mined coal seam are used to study the variation in gas drainage from a coal seam during mining.The results show that mining can increase the permeability of a coal seam,which then increases the gas drainage.There are inflection points in this variation over time.A close relationship between this variation and the rate of change in coal seam permeability is observed.

  4. Conversion of coal mine drainage ochre to water treatment reagent: Production, characterisation and application for P and Zn removal.

    Sapsford, Devin; Santonastaso, Marco; Thorn, Peter; Kershaw, Steven

    2015-09-01

    Coal mine drainage ochre is a ferruginous precipitate that forms from mine water in impacted watercourses and during treatment. With thousands of tonnes per annum of such ochre arising from mine water treatment in the UK alone, management of these wastes is a substantive issue. This paper demonstrates that the ochre from both active and passive treatment of coal mine drainage can be transformed into an effective water treatment reagent by simple acid dissolution and that the reagent can be used for the removal of dissolved phosphorous from municipal wastewater and zinc from non-coal mine waters. Ochre is readily soluble in H2SO4 and HCl. Ochre is more soluble in HCl with solubilities of up to 100 g/L in 20% (w/w) HCl and 68 g/L in 10% (w/w) H2SO4. For four of the eight tested ochres solubility decreased in higher concentrations of H2SO4. Ochre compositional data demonstrate that the coal mine ochres tested are relatively free from problematic levels of elements seen by other authors from acid mine drainage-derived ochre. Comparison to British Standards for use of iron-based coagulants in drinking water treatment was used as an indicator of the acceptability of use of the ochre-derived reagents in terms of potentially problematic elements. The ochre-derived reagents were found to meet the 'Grade 3' specification, except for arsenic. Thus, for application in municipal wastewater and mine water treatment additional processing may not be required. There was little observed compositional difference between solutions prepared using H2SO4 or HCl. Ochre-derived reagents showed applicability for the removal of P and Zn with removals of up to 99% and 97% respectively measured for final pH 7-8, likely due to sorption/coprecipitation. Furthermore, the results demonstrate that applying a Fe dose in the form of liquid reagent leads to a better Fe:P and Fe:Zn removal ratio compared to ochre-based sorption media tested in the literature. PMID:26081304

  5. Effects of longwall mining subsidence on ground water levels within a watershed hydraulically isolated from mine drainage

    Surface and ground water resources are effectively preserved from depletion by underground mine drainage if impervious deposits of sufficient thickness and extent that underlie the aquifer avoid fracturing and undergo only plastic deformation resulted from the strata flexure. This does not mean, however, that these waters are not subjected to the effects of mining disturbance. Differential vertical settlement of the mine overburden and the ground surface can significantly affect flow pattern and water retention within a watershed area. This is evident, for example, in the areas of multiseam coal mining where the longwall method is used. The effects of this type of mining on water level were tested in a selected watershed where shallow water bearing deposits were entirely isolated from underground mine pumpage. Results of more than 7 years of field investigations were compared with data collected from other coal mining areas of various hydrogeological conditions. The study revealed a variety of water table responses on the postmining subsidence. Basically, changes of water table height in a given site above the point located at the top of aquifer base depend mainly on alteration of that point position against the local drainage base in the hierarchic structure of flow system. The relationship between the magnitude of ground subsidence and water level decline varies within the area of the subsidence trough, within the watershed, and among various watersheds of different hydrogeologic conditions. Except for the situation of hydrostatic flow conditions, lowering of water table elevation in response to the settlement of aquifer base was observed

  6. PHYSICAL SOLUTIONS FOR ACID MINE DRAINAGE AT REMOTE MINE SITES

    After completing extensive bench-scale testing to determine optimum treatment approaches, the technology has been taken to the field. Preliminary results show that calcium hydroxide precipitates the bulk of the arsenic and zinc; the granular ferric hydroxide removes the rest of ...

  7. Assessing the utility of mixed organic materials for removal of metals in mine drainage impacted waters

    Song, H.; Neculita, C.; Lee, G.; Jeong, J.; Cho, D.; Chang, S.

    2010-12-01

    The use of natural organic materials in bioreactors is one of the most sustainable technologies for treatment of metals in mine-impacted waters. Several natural organic substrates including mushroom compost, cow manure, sawdust, wood chips, and cut rice straw were characterized and used in combination for treating mine drainage with acidic (pH 3) and moderate pH (pH 6). Bench-scale batch experiments were performed for 35-day period to evaluate the performance of organic substrates in removing dissolved metals. Overall results indicated that mixtures of different substrates showed satisfactory performances in removing metals (Al > Fe > Mn) (up to 100%), generating alkalinity, and reducing sulfate at both pH conditions. The mixture of sawdust and cow manure was found as the most effective whereas the mixture containing 40% cut rice straw gave limited efficiency, suggesting organic carbon released from this substrate is not readily available for biodegradation under anaerobic conditions. The mushroom compost based bioreactors released significant amount of sulfate, which may raise a concern upon the start-up of field-scale bioreactors. Collectively, the substrate mixtures had comparable performances to the mushroom compost, the most commonly used material in field bioreactors, in terms of metal removal, pH neutralization, and sulfate reduction, except for the reactors containing rice straw. Especially, the mixture of sawdust and cow manure was the most efficient substrate for treatment of mine-impacted waters. The correlation between the extent of sulfate reduction and dissolved organic carbon/SO42- ratio was weak and this indicates the type of DOC plays more important role in sulfate reduction than the absolute concentration and that the ratio is not sensitive enough to properly describe the relative effectiveness of substrate mixtures.

  8. Microbial communities in riparian soils of a settling pond for mine drainage treatment.

    Fan, Miaochun; Lin, Yanbing; Huo, Haibo; Liu, Yang; Zhao, Liang; Wang, Entao; Chen, Weimin; Wei, Gehong

    2016-06-01

    Mine drainage leads to serious contamination of soil. To assess the effects of mine drainage on microbial communities in riparian soils, we used an Illumina MiSeq platform to explore the soil microbial composition and diversity along a settling pond used for mine drainage treatment. Non-metric multidimensional scaling analysis showed that the microbial communities differed significantly among the four sampling zones (influent, upstream, downstream and effluent), but not seasonally. Constrained analysis of principal coordinates indicated heavy metals (zinc, lead and copper), total sulphur, pH and available potassium significantly influenced the microbial community compositions. Heavy metals were the key determinants separating the influent zone from the other three zones. Lower diversity indices were observed in the influent zone. However, more potential indicator species, related to sulphur and organic matter metabolism were found there, such as the sulphur-oxidizing genera Acidiferrobacter, Thermithiobacillus, Limnobacter, Thioprofundum and Thiovirga, and the sulphur-reducing genera Desulfotomaculum and Desulfobulbus; the organic matter degrading genera, Porphyrobacter and Paucimonas, were also identified. The results indicated that more microorganisms related to sulphur- and carbon-cycles may exist in soils heavily contaminated by mine drainage. PMID:27055175

  9. Microbial communities in acid water environments of two mines, China

    Xiao Shengmu; Xie Xuehui [College of Environmental Science and Engineering, Donghua University, Shanghai (China); Liu Jianshe [College of Environmental Science and Engineering, Donghua University, Shanghai (China); School of Resources Processing and Bioengineering, Central South University, Changsha (China)], E-mail: xiaoshengmu@gmail.com

    2009-03-15

    To understand the compositions and structures of microbial communities in different acid-aqueous environments, a PCR-based cloning approach was used. A total of five samples were collected from two mines in China. Two samples, named as G1 and G2, were acid mine drainage (AMD) samples and from Yunfu sulfide mine in Guangdong province, China. The rest of the three samples named as D1, DY and D3, were from three sites undertaking bioleaching in Yinshan lead-zinc mine in Jiangxi province, China. Phylogenetic analysis revealed that bacteria in the five samples fell into six putative divisions, which were {alpha}-Proteobacteria, {beta}-Proteobacteria, {gamma}-Proteobacteria, Firmicutes, Actinobacteria and Nitrospira. Archaea was only detected in the three samples from Yinshan lead-zinc mine, which fell into two phylogenentic divisions, Thermoplsma and Ferroplasma. In addition, the results of principal component analysis (PCA) suggested that more similar the geochemical properties in samples were, more similar microbial community structures in samples were. - Microbial community compositions in acid-aqueous environments from Chinese mines were studied, and the relationship with geochemical properties was obtained.

  10. Microbial communities in acid water environments of two mines, China

    To understand the compositions and structures of microbial communities in different acid-aqueous environments, a PCR-based cloning approach was used. A total of five samples were collected from two mines in China. Two samples, named as G1 and G2, were acid mine drainage (AMD) samples and from Yunfu sulfide mine in Guangdong province, China. The rest of the three samples named as D1, DY and D3, were from three sites undertaking bioleaching in Yinshan lead-zinc mine in Jiangxi province, China. Phylogenetic analysis revealed that bacteria in the five samples fell into six putative divisions, which were α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Firmicutes, Actinobacteria and Nitrospira. Archaea was only detected in the three samples from Yinshan lead-zinc mine, which fell into two phylogenentic divisions, Thermoplsma and Ferroplasma. In addition, the results of principal component analysis (PCA) suggested that more similar the geochemical properties in samples were, more similar microbial community structures in samples were. - Microbial community compositions in acid-aqueous environments from Chinese mines were studied, and the relationship with geochemical properties was obtained

  11. Microbial influences during mining and usage of coal

    A range of interactions of microorganisms with coal is considered. Topics include: coal biodegradation; microorganisms and acid mine drainage; biological treatment of acid coal mine drainage; and bacteria and fly ash leaching. 68 refs

  12. Metal mobility in river and sea sediments affected by mine drainage (Sestri Levante, Italy)

    Consani, Sirio; Capello, Marco; Cutroneo, Laura; Vagge, Greta; Zuccarelli, Andrea; Carbone, Cristina

    2016-04-01

    The Gromolo Torrent is a metal-polluted Apennine streamflow located near Sestri Levante (Liguria, Italy). It springs from the Monte Rocca Grande (850 m a.s.l.), and flows for 11.5 km through the Gromolo Valley before flowing into the Ligurian Sea. Inside the Gromolo basin is located the abandoned Fe-Cu mine of Libiola, which was the most important sulfide deposit of the Ligurian Apennines. In this mining site, extensive Acid Mine Drainage (AMD) processes are active, both inside the mine tunnels and in the sulfide rich waste-rock dumps; the solutions generated are characterised by low pH values and high amounts of dissolved SO42-, Fe, and other chemical elements such as Cu, Zn, Pb, Al, Co, and Ni. Moreover, exstensively precipitation of Fe and Cu-rich secondary minerals occurs both as soft crusts inside the mine adits and as loose suspensions associated with overland flow of mine drainage. AMD waters flowed into the uncontaminated Gromolo Torrent where abundant precipitation of amorphous Fe(III)-oxy-hydroxides occurred. The marine study area is characterised by the presence of the headland of Sestri Levante with two bays, the western one named "Baia delle Favole". The dynamics of the area is dominated by a permanent north-westward off-shore current flowing approximately along isobath, and an eastward counter-current along the north coast with a resulting drift of the coastal materials from the West to Est towards "Baia delle Favole". The bottom sediment are principally characterised by coarse materials, mostly consisting of fine sand, with a percentage of the fine sediment increasing inside the bay, where the dynamics is low. The aims of this work are to 1) evaluate the metal mobility of colloidal river precipitates for about 7 km up to its mouth in the Ligurian Sea; 2) verify the contamination state of the marine bottom sediments off the mouth of the Gromolo Torrent ("Baia delle Favole" of Sestri Levante), and 3) identify the main sources and diffusion ways of

  13. Evaluation of design factors for a cascade aerator to enhance the efficiency of an oxidation pond for ferruginous mine drainage.

    Oh, Chamteut; Ji, Sangwoo; Cheong, Youngwook; Yim, Giljae; Hong, Ji-Hye

    2016-10-01

    This research focused on the optimum design of a cascade aerator to enhance the efficiency of an oxidation pond in a passive treatment system for remediating ferruginous mine drainage. For this purpose, various aeration experiments with aerators of different drop heights (0-4 m) and formations (types A and B) were executed on mine drainage. Type A simply drops the mine drainage into the oxidation pond while type B sprays the mine drainage and retains it for 8 min in each step. The efficiency enhancement of the oxidation pond was strongly dependent on the increase in pH and DO of the mine drainage discharged into the pond. The water quality improved with the increase in drop height but especially showed better effect with type B. The reasons for this result were attributed to the increase of contact surface and retention time of the mine drainage. The cascade aerator, therefore, should be designed to be as high as possible with the assistance of spraying form and retention time of the mine drainage to maximize the efficiency of the oxidation pond. These effects could be evaluated by calculating required areas of the oxidation pond for 95% of Fe(2+) oxidation. PMID:26936197

  14. Geophysical delineation of acidity and salinity in the Central Manitoba gold mine tailings pile, Manitoba, Canada

    Tycholiz, C.; Ferguson, I. J.; Sherriff, B. L.; Cordeiro, M.; Sri Ranjan, R.; Pérez-Flores, M. A.

    2016-08-01

    Surface electrical and electromagnetic geophysical methods can map enhanced electrical conductivity caused by acid mine drainage in mine tailings piles. In this case study, we investigate quantitative relationships between geophysical responses and the electrical conductivity, acidity and salinity of tailing samples at the Central Manitoba Mine tailings in Manitoba, Canada. Previous electromagnetic surveys at the site identified zones of enhanced conductivity that were hypothesized to be caused by acid mine drainage. In the present study, high-resolution EM31 and DC-resistivity measurements were made on a profile through a zone of enhanced conductivity and laboratory measurements of salinity and pH were made on saturation paste extracts from an array of tailing samples collected from the upper 2 m of tailings along the profile. Observed spatial correlation of pH and pore-fluid salinity in the tailings samples confirms that the enhanced conductivity in the Central Manitoba Mine tailings is due to acid mine drainage. Contoured cross-sections of the data indicate that the acid mine drainage is concentrated near the base of the oxidized zone in the thicker parts of the tailings pile. The zone of increased acidity extends to the surface on sloping margins causing an increase in apparent conductivity in shallow penetrating geophysical responses. The quantitative relationship between measured pH and salinity shows that the conductivity increase associated with the acid mine drainage is due only in part to conduction by ions produced from dissociation of sulfuric acid. Comparison of the observations with fluid conductivity estimates based on statistical relationships of pH and ion concentrations in water samples from across the tailings pile shows that Ca2 + and Mg2 + ions also make significant contributions to the conductivity at all values of pH and Cu2 +, Al3 + and Fe3 + ions make additional contributions at low pH. Variability in the measured conductivity at constant

  15. Isotopic composition of water from a mine drainage site in Creede County in south central Colorado

    Michel, R. L.; Williams, M. W.; Krupicka, A.; Wireman, M.; Graves, J.

    2011-12-01

    Creede County in South Central Colorado was an active area of silver mining beginning in the early 1890s. To relieve flooding in some of the mines, the Nelson Tunnel was built in the late 1890s. This tunnel still exists and acid mine drainage from the tunnel eventually flows into the Willow Creek Watershed which eventually flows into the Upper Rio Grande. The water coming out of the tunnel is high in toxic metals and the area has become part of an EPA Superfund site in an effort to find a suitable method to remediate the metal problems. Among the approaches used in the program is the use of isotopes of water and carbon to identify sources and estimate ages of the water in the drainage. Samples were collected for analysis of isotopic ratios and tritium concentrations at a series of sites within the tunnel complex from 2008-2010. In 2009 samples were also collected for analysis of isotopes in groundwater and surface water. In 2010 sampling was expanded to include four precipitation and one snow sample. Tritium concentrations in precipitation and snowfall in 2010 ranged from 3-6 tritium units with the lowest concentration found in the snow sample. The 18O isotopic ratios in precipitation for this site ranged from an average of -8.9 o/oo in summer to about -19 o/oo in winter. The six groundwater samples collected in 2009 had an average 18O isotopic concentration of -15 o/oo and tritium concentrations ranging from 7.4-9.3 TU. These results suggest that the groundwater sampled is composed largely of a mixture of summer and winter precipitation with the latter source being dominant. The tritium concentrations in groundwater exceed recent precipitation concentrations, suggesting the presence of water from the bomb-tritium transient and an age of a decade or more for the groundwater. Eight sites in the tunnel were sampled I from 2008-2010, although not all sites were sampled every year. The sampling sites included waters seeping into the tunnel as well as the outlet water

  16. Pretreatment of highly turbid coal mine drainage by a chemical agent free filtration system

    Zhang Chunhui; He Xiong; Li Kaihe; Wu Dongsheng; Guo Yanrong; Wang Can

    2012-01-01

    A filtration system used without chemical agents for the pretreatment of turbid coal mine drainage is described in this paper.The influence of different aperture sizes and different motor speeds was investigated during the study.The experimental results show that for aperture diameters of 0.4,0.6,or 0.8 mm smaller apertures provide more complete filtration.Rotations of 12,20,28,or 40 r/min show that higher speeds give more efficient filtration.Suspended solids decreased in both particle size and concentration after the filtration.The separated slime can be directly reused as a fuel.Efficient filtration pretreatment systems for coal mine drainage were investigated and the economic feasibility is analyzed in this article.

  17. Mixing-controlled uncertainty in long-term predictions of acid rock drainage from heterogeneous waste-rock piles

    Pedretti, D.; Beckie, R. D.; Mayer, K. U.

    2015-12-01

    The chemistry of drainage from waste-rock piles at mine sites is difficult to predict because of a number of uncertainties including heterogeneous reactive mineral content, distribution of minerals, weathering rates and physical flow properties. In this presentation, we examine the effects of mixing on drainage chemistry over timescales of 100s of years. We use a 1-D streamtube conceptualization of flow in waste rocks and multicomponent reactive transport modeling. We simplify the reactive system to consist of acid-producing sulfide minerals and acid-neutralizing carbonate minerals and secondary sulfate and iron oxide minerals. We create multiple realizations of waste-rock piles with distinct distributions of reactive minerals along each flow path and examine the uncertainty of drainage geochemistry through time. The limited mixing of streamtubes that is characteristic of the vertical unsaturated flow in many waste-rock piles, allows individual flowpaths to sustain acid or neutral conditions to the base of the pile, where the streamtubes mix. Consequently, mixing and the acidity/alkalinity balance of the streamtube waters, and not the overall acid- and base-producing mineral contents, control the instantaneous discharge chemistry. Our results show that the limited mixing implied by preferential flow and the heterogeneous distribution of mineral contents lead to large uncertainty in drainage chemistry over short and medium time scales. However, over longer timescales when one of either the acid-producing or neutralizing primary phases is depleted, the drainage chemistry becomes less controlled by mixing and in turn less uncertain. A correct understanding of the temporal variability of uncertainty is key to make informed long-term decisions in mining settings regarding the management of waste material.

  18. Filter materials for metal removal from mine drainage--a review.

    Westholm, Lena Johansson; Repo, Eveliina; Sillanpää, Mika

    2014-01-01

    A large number of filter materials, organic and inorganic, for removal of heavy metals in mine drainage have been reviewed. Bark, chitin, chitosan, commercial ion exchangers, dairy manure compost, lignite, peat, rice husks, vegetal compost, and yeast are examples of organic materials, while bio-carbons, calcareous shale, dolomite, fly ash, limestone, olivine, steel slag materials and zeolites are examples of inorganic materials. The majority of these filter materials have been investigated in laboratory studies, based on various experimental set-ups (batch and/or column tests) and different conditions. A few materials, for instance steel slag materials, have also been subjects to field investigations under real-life conditions. The results from these investigations show that steel slag materials have the potential to remove heavy metals under different conditions. Ion exchange has been suggested as the major metal removal mechanisms not only for steel slag but also for lignite. Other suggested removal mechanisms have also been identified. Adsorption has been suggested important for activated carbon, precipitation for chitosan and sulphate reduction for olivine. General findings indicate that the results with regard to metal removal vary due to experimental set ups, composition of mine drainage and properties of filter materials and the discrepancies between studies renders normalisation of data difficult. However, the literature reveals that Fe, Zn, Pb, Hg and Al are removed to a large extent. Further investigations, especially under real-life conditions, are however necessary in order to find suitable filter materials for treatment of mine drainage. PMID:24781327

  19. Surface hydrology of drainage basins disturbed by surface mining and reclamation, central Pennsylvania

    Infilration capacity of newly reclaimed minesoils is uniformly low (< 1 cm/hr) and generally increases (up to 6 cm/hr) with age, the magnitude of increase being dependent on soil characteristics and vegetation. In drainage basins with lower rates of infiltration recovery (< 2 cm/hr), infiltration-excess overland flow is the dominant runoff process. Increased peek runoff rate and stream power in the basins are sufficient to initiate drainage network evolution, with phases of network expansion and abstraction. In contrast, in basins where infiltration recovery is greater than 2 cm/hr, the hydrologic system is initially dominated by infiltration-excess overland flow but evolves toward a system dominated by saturation overland flow. Drainage development is limited to skeletal network initiation and elongation and occurs during the early period of infiltration-excess dominated flow conditions. Total runoff remains essentially constant due to increased proportions of return flow, reflected in the extended and less steep recession limb of saturation-dominated storm hydrographs. The results of this study are applicable to hydrologic prediction for purposes of surface mine permitting and reclamation design. Previously limited availability of rainfall-runoff data from watersheds disturbed by surface mining preclude adequate calibration of empirical methods, such as the runoff curve number method, or evaluation of a more sophisticated approach, such as the use of distributed hydrologic models, for hydrologic prediction. Runoff curve numbers calibrated by means of rainfall-runoff data from the study drainage basins indicate that presently accepted methods of determining curve numbers, using pre-mine soil classification, underestimate total runoff by as much as 50%

  20. Cinza e carbonato de cálcio na mitigação de drenagem ácida em estéril de mineração de carvão Coal ash and calcium carbonate on acid drainage mitigation in coal mining overburden

    Evaldo Rodrigues Soares

    2006-02-01

    ção da drenagem ácida devem ser estimuladas.Acid drainage is an environmental problem, not exclusive, but commonly associated to coal mines. It arises from the oxidation of sulfides, like pyrite, in overburden and mining tailings. The use of ashes from coal combustion is still limited in Brazil, but such residues have a potential use as neutralizing agent for acid mine drainage. This study intended to evaluate the interaction between the use of coal ash and CaCO3 to neutralize acid drainage from pyrite oxidation in coal mining overburden from Candiota (RS - Brazil. Samples of overburden material containing pyrite were treated with increasing CaCO3 doses and coal ash in leaching flasks. The treatments were disposed in a completely randomized design in 4 x 4 factorial scheme (4 doses of CaCO3 and 4 doses of coal ash with three replications. The flasks were submitted every two weeks to leaching with distilled water during eight months. The leached solutions were analyzed for pH, free acidity and S, Si and Fe contents. Results showed that the use of ash was impractical not only due to its low neutralizing capacity, but also because it reduced the CaCO3 efficiency. After eight months of simulated weathering only 11% of the sulfides were oxidized in the absence of ash or carbonate. The use of CaCO3 and, to a lesser extent of ash, increased the pyrite oxidation rate. Pyrite in coal overburden oxidized faster in the first two months of simulated weathering, thus it is recommended that lime be applied just after overburden exposition in order to minimize acid drainage. Further investigation aiming to optimize the CaCO3 doses and test alternative neutralizing materials in long term experiments should be encouraged.

  1. Computational Fluid Dynamics Simulation of Oxygen Seepage in Coal Mine Goaf with Gas Drainage

    Guo-Qing Shi

    2015-01-01

    Full Text Available Mine fires mainly arise from spontaneous combustion of coal seams and are a global issue that has attracted increasing public attention. Particularly in china, the closure of coal workfaces because of spontaneous combustion has contributed to substantial economic loss. To reduce the occurrence of mine fires, the spontaneous coal combustion underground needs to be studied. In this paper, a computational fluid dynamics (CFD model was developed for coal spontaneous combustion under goaf gas drainage conditions. The CFD model was used to simulate the distribution of oxygen in the goaf at the workface in a fully mechanized cave mine. The goaf was treated as an anisotropic medium, and the effects of methane drainage and oxygen consumption on spontaneous combustion were considered. The simulation results matched observational data from a field study, which indicates CFD simulation is suitable for research on the distribution of oxygen in coalmines. The results also indicated that near the workface spontaneous combustion was more likely to take place in the upper part of the goaf than near the bottom, while further from workface the risk of spontaneous combustion was greater in the lower part of the goaf. These results can be used to develop firefighting approaches for coalmines.

  2. Field application of selective precipitation for recovering Cu and Zn in drainage discharged from an operating mine.

    Oh, Chamteut; Han, Young-Soo; Park, Jin Hee; Bok, Songmin; Cheong, Youngwook; Yim, Giljae; Ji, Sangwoo

    2016-07-01

    Acid mine drainage (AMD) generated from mining activities has been recognized as a serious problem due to its increased acidity and high concentration of heavy metals. In this research, a feasibility test of the selective precipitation (SP) process was performed using AMD discharged from a currently operating mine in Korea for the purpose of minimizing the environmental impact of AMD. For the SP process, a pilot scale equipment (100L reaction tank) was used in field and among various metals, Cu and Zn were the target metals. Through the research, it was confirmed that AMD from an operating mine has two disadvantages of being applied to the SP: altering water quality and unexpected inclusion of clay debris. Despite unfavorable conditions, Cu and Zn precipitate of 80% purity with 90% precipitation rate was able to be obtained from 1.4L/min (2.0tons/day) AMD. The recovered precipitates were identified as amorphous CuS and ZnS with small amounts of impurities (Si minerals, CuFeS2, and Fe/Al hydroxide). The strategies to reduce these impurities were also discussed. Recovery rate, which is the amount of precipitate collected per unit volume of AMD, was proposed as an indicator to evaluate the working efficiency of the SP process. It was confirmed that the recovery rate was strongly dependent on flow rate and dose of coagulant. The results of this study may be helpful in reducing the potential complications which occurs when SP is applied on field. PMID:26994808

  3. Acidic Microenvironments in Waste Rock Characterized by Neutral Drainage: Bacteria–Mineral Interactions at Sulfide Surfaces

    John W. Dockrey

    2014-03-01

    Full Text Available Microbial populations and microbe-mineral interactions were examined in waste rock characterized by neutral rock drainage (NRD. Samples of three primary sulfide-bearing waste rock types (i.e., marble-hornfels, intrusive, exoskarn were collected from field-scale experiments at the Antamina Cu–Zn–Mo mine, Peru. Microbial communities within all samples were dominated by neutrophilic thiosulfate oxidizing bacteria. However, acidophilic iron and sulfur oxidizers were present within intrusive waste rock characterized by bulk circumneutral pH drainage. The extensive development of microbially colonized porous Fe(III (oxyhydroxide and Fe(III (oxyhydroxysulfate precipitates was observed at sulfide-mineral surfaces during examination by field emission-scanning electron microscopy-energy dispersive X-ray spectroscopy (FE-SEM-EDS. Linear combination fitting of bulk extended X-ray absorption fine structure (EXAFS spectra for these precipitates indicated they were composed of schwertmannite [Fe8O8(OH6–4.5(SO41–1.75], lepidocrocite [γ-FeO(OH] and K-jarosite [KFe3(OH6(SO42]. The presence of schwertmannite and K-jarosite is indicative of the development of localized acidic microenvironments at sulfide-mineral surfaces. Extensive bacterial colonization of this porous layer and pitting of underlying sulfide-mineral surfaces suggests that acidic microenvironments can play an important role in sulfide-mineral oxidation under bulk circumneutral pH conditions. These findings have important implications for water quality management in NRD settings.

  4. A cost comparison study of open pit mining vs. in situ assisted gravity drainage

    The twin-well steam assisted gravity drainage (SAGD) process has resulted in breakthrough technology to access previously uneconomical deep-seated oil sands reserves in Alberta, and to provide a very cost-effective and environmentally acceptable method for extracting bitumen from reserves having a minimum of 30 m overburden. In the evaluation of new or improved bitumen recovery technologies for its new North Mine, Syncrude Canada has recognized that SAGD was a potential alternate to the current open pit mining and hot water extraction process. A study was conducted to compare and evaluate bitumen recovery by the two schemes at the North Mine site, scheduled to begin operations in 1996, for the reserves under Syncrude's tailings pond, and at a new grassroots area. Study description and analysis of results are presented for the grassroots case. The assumptions and mining/recovery processes used for the mining or SAGD method are detailed and the advantages and drawbacks of each scheme are noted. Results show that the SAGD unit supply costs are projected to be proportionately lower than the corresponding open pit mining/hot water extraction (OP/X) cost, using a 20-y project life. A sensitivity analysis indicates that the SAGD process is more sensitive to natural gas costs, while the OP/X scheme is more sensitive to power costs. The SAGD process is much less labor-intensive than OP/X and has obvious advantages in terms of tailings disposal and post-mining reclamation. In addition, the underground nature of SAGD operation eliminates adverse effects of the weather on working conditions. 11 figs

  5. Impact of AMD on water quality in critical watershed in the Hudson River drainage basin: Phillips Mine, Hudson Highlands, New York

    Gilchrist, S.; Gates, A.; Szabo, Z.; Lamothe, P.J.

    2009-01-01

    A sulfur and trace element enriched U-Th-laced tailings pile at the abandoned Phillips Mine in Garrison, New York, releases acid mine drainage (AMD, generally pH < 3, minimum pH 1.78) into the first-order Copper Mine Brook (CMB) that drains into the Hudson River. The pyrrhotite-rich Phillips Mine is located in the Highlands region, a critical water source for the New York metro area. A conceptual model for derivation/dissolution, sequestration, transport and dilution of contaminants is proposed. The acidic water interacts with the tailings, leaching and dissolving the trace metals. AMD evaporation during dry periods concentrates solid phase trace metals and sulfate, forming melanterite (FeSO4???7H2O) on sulfide-rich tailings surfaces. Wet periods dissolve these concentrates/precipitates, releasing stored acidity and trace metals into the CMB. Sediments along CMB are enriched in iron hydroxides which act as sinks for metals, indicating progressive sequestration that correlates with dilution and sharp rise in pH when mine water mixes with tributaries. Seasonal variations in metal concentrations were partly attributable to dissolution of the efflorescent salts with their sorbed metals and additional metals from surging acidic seepage induced by precipitation. ?? 2008 Springer-Verlag.

  6. Evaluation of natural amelioration of acidic deep mine discharges in Western Pennsylvania

    Abandoned mine drainage (AMD) has long been the most serious water quality and watershed degradation problem in the Appalachian region of the U.S. and in some other areas of the nation. In several areas of western Pennsylvania, deep mine discharges that were reliably described as highly acidic in the 1960s and 1970s have shown natural amelioration of CO2 acidity. A number of different factors, including mine flooding and overburden chemistry, may cause improvement in mine water quality. The authors are studying the hydrologic and geochemical factors responsible for improvements over time in the quality of water discharges from abandoned deep mines. The project is focused on the study of a set of mine water discharges associated with abandoned, interconnected deep mines in the Uniontown Syncline of Western Pennsylvania. This area was studied extensively under Pennsylvania's Operation Scarlift in the early 1970s, and one year of monthly water quality data are available from 1974-75. The mined-out coal basin of the Uniontown Syncline is unique in that different mining methods were employed in the same coal seam over the basin. The resulting discharges are from flooded, unflooded, and partially flooded abandoned underground coal mines. This paper presents an overview of the hydraulic system in the mine network of the Uniontown Syncline along with a summary of selected data from the 1974-75 and 1998-99 studies. Preliminary interpretations of these data in relation to the Scarlift data are also presented

  7. Abandoned mine drainage in the Swatara Creek Basin, southern anthracite coalfield, Pennsylvania, USA: 2. performance of treatment systems

    Cravotta, Charles A., III

    2010-01-01

    A variety of passive and semi-passive treatment systems were constructed by state and local agencies to neutralize acidic mine drainage (AMD) and reduce the transport of dissolved metals in the upper Swatara Creek Basin in the Southern Anthracite Coalfield in eastern Pennsylvania. To evaluate the effectiveness of selected treatment systems installed during 1995–2001, the US Geological Survey collected water-quality data at upstream and downstream locations relative to each system eight or more times annually for a minimum of 3 years at each site during 1996–2007. Performance was normalized among treatment types by dividing the acid load removed by the size of the treatment system. For the limestone sand, open limestone channel, oxic limestone drain, anoxic limestone drain (ALD), and limestone diversion well treatment systems, the size was indicated by the total mass of limestone; for the aerobic wetland systems, the size was indicated by the total surface area of ponds and wetlands. Additionally, the approximate cost per tonne of acid treated over an assumed service life of 20 years was computed. On the basis of these performance metrics, the limestone sand, ALD, oxic limestone drain, and limestone diversion wells had similar ranges of acid-removal efficiency and cost efficiency. However, the open limestone channel had lower removal efficiency and higher cost per ton of acid treated. The wetlands effectively attenuated metals transport but were relatively expensive considering metrics that evaluated acid removal and cost efficiency. Although the water-quality data indicated that all treatments reduced the acidity load from AMD, the ALD was most effective at producing near-neutral pH and attenuating acidity and dissolved metals. The diversion wells were effective at removing acidity and increasing pH of downstream water and exhibited unique potential to treat moderate to high flows associated with storm flow conditions.

  8. Attenuation of dissolved metals in neutral mine drainage in the Zambian Copperbelt.

    Sracek, Ondra; Filip, Jan; Mihaljevič, Martin; Kříbek, Bohdan; Majer, Vladimír; Veselovský, František

    2011-01-01

    Behaviour of metals like Cu and Co was studied in nearly neutral (pH ≥ 6.4) mine drainage seepage in a stream downgradient of a tailing dam at Chambishi site in the Copperbelt of Zambia. They are attenuated by precipitation of ferruginous ochres that incorporate significant quantities of metals. Using chemical analysis, X-ray powder diffraction and Mössbauer spectroscopy, we show that the ochres are composed mostly of amorphous ferric hydroxide. Close to the seepage face, the total Fe content of ochres increases due to precipitation of amorphous ferric hydroxide, but total Fe in sediment decreases further downstream. The stream then flows through wetland (dambo) where the remaining fraction of metals is removed. During rainy periods, increased flow rate may result in re-suspension of ochres, increasing thus the mobility of metals. Major ions like sulphate are conservative at the start of the dry period (May), but gypsum may probably precipitate later at the end of the dry period. Sequential extractions of bulk sediments indicate that Mn behaves differently to Fe, with a trend of increasing Mn with distance from the tailing dam. There is much more Fe than Mn in residual (Aqua Regia) fraction, indicating that amorphous ferric hydroxides are transformed to more crystalline phases deeper in sediment. Environmental impact of mine drainage is relatively limited due to its neutral character. PMID:20140501

  9. Removal of chromium and toxic ions present in mine drainage by Ectodermis of Opuntia

    Barrera, Hector [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon interseccion Paseo Tollocan S/N, C.P. 50120, Toluca, Estado de Mexico (Mexico); Urena-Nunez, Fernando [Instituto Nacional de Investigaciones Nucleares, A.P.18-1027, Col. Escandon, Delegacion Miguel Hidalgo, C.P. 11801, Mexico, D.F. (Mexico); Bilyeu, Bryan [University of North Texas, Department of Materials Science and Engineering, P.O. Box 305310, Denton, TX 76203-5310 (United States); Barrera-Diaz, Carlos [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon interseccion Paseo Tollocan S/N, C.P. 50120, Toluca, Estado de Mexico (Mexico)]. E-mail: cbarrera@uaemex.mx

    2006-08-25

    This work presents conditions for hexavalent and trivalent chromium removal from aqueous solutions using natural, protonated and thermally treated Ectodermis of Opuntia. A removal of 77% of Cr(VI) and 99% of Cr(III) can be achieved. The sorbent material is characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy, infrared spectroscopy, thermogravimetric analysis, before and after the contact with the chromium containing aqueous media. The results obtained from the characterization techniques indicate that the metal ion remains on the surface of the sorbent material. The percentage removal is found to depend on the initial chromium concentration and pH. The Cr(VI) and Cr(III) uptake process is maximum at pH 4, using 0.1 g of sorbent per liter of aqueous solution. The natural Ectodermis of Opuntia showed a chromium adsorption capacity that was adequately described by the Langmuir adsorption isotherm. Finally, an actual mine drainage sample that contained Cd, Cr, Cu, Fe Zn, Ni and Pb was tested under optimal conditions for chromium removal and Ectodermis of Opuntia was found to be a suitable sorbent material. The use of this waste material for the treatment of metal-containing aqueous solutions as well as mine drainage is effective and economical.

  10. Simulation of mine drainage for preliminary development of oil shale and associated minerals, Piceance basin, northwestern Colorado

    Taylor, O. James

    1986-01-01

    The Piceance basin of northwestern Colorado contains large resources of oil shale, nahcolite, and dawsonite. Development of these minerals will require drainage of water from mines. A six-layer hydrologic model of the basin was prepared to simulate mine drainage for mineral development. Streams and major tributaries were simulated as head-dependent nodes. Stream nodes were gaining or losing, but the rate of loss was constrained by the leakance of the streambed and the stream stage. Springs also were simulated as head-dependent nodes that stop flowing if the aquifer head declines below the spring orifice. (USGS)

  11. Treatment of antimony mine drainage: challenges and opportunities with special emphasis on mineral adsorption and sulfate reducing bacteria.

    Li, Yongchao; Hu, Xiaoxian; Ren, Bozhi

    2016-01-01

    The present article summarizes antimony mine distribution, antimony mine drainage generation and environmental impacts, and critically analyses the remediation approach with special emphasis on iron oxidizing bacteria and sulfate reducing bacteria. Most recent research focuses on readily available low-cost adsorbents, such as minerals, wastes, and biosorbents. It is found that iron oxides prepared by chemical methods present superior adsorption ability for Sb(III) and Sb(V). However, this process is more costly and iron oxide activity can be inhibited by plenty of sulfate in antimony mine drainage. In the presence of sulfate reducing bacteria, sulfate can be reduced to sulfide and form Sb2S3 precipitates. However, dissolved oxygen and lack of nutrient source in antimony mine drainage inhibit sulfate reducing bacteria activity. Biogenetic iron oxide minerals from iron corrosion by iron-oxidizing bacteria may prove promising for antimony adsorption, while the micro-environment generated from iron corrosion by iron oxidizing bacteria may provide better growth conditions for symbiotic sulfate reducing bacteria. Finally, based on biogenetic iron oxide adsorption and sulfate reducing bacteria followed by precipitation, the paper suggests an alternative treatment for antimony mine drainage that deserves exploration. PMID:27148704

  12. A Sustainable Approach for Acid Rock Drainage Treatment using Clinoptilolite

    Li, L. Y.; Xu, W.; Grace, J. R.

    2009-04-01

    Problems related to acid rock drainage (ARD) occur along many highways of British Columbia. The ARD problem at Pennask Creek along Highway 97C in the Thompson-Okanagan region is an ideal site for pilot study to investigate a possible remediation solution. The highway was opened in 1991. An ARD problem was identified in 1997. Both sides of Highway 97C are producing acidified runoff from both cut rock surface and a fractured ditch. This runoff eventually enters Pennask Creek, the largest spawning source of rainbow trout in British Columbia. The current remediation technique using limestone for ARD treatment appears to be unnecessarily expensive, to generate additional solid waste and to not be optimally effective. A soil mineral natural zeolite - clinoptilolite - which is inexpensive and locally available, has a high metal adsorption capacity and a significant buffering capacity. Moreover, the clinoptilolite materials could be back-flushed and reused on site. An earlier batch adsorption study from our laboratory demonstrated that clinoptilolite has a high adsorption capacity for Cu, Zn, Al, with adsorption concentrations 131, 158 and 215 mg/kg clinoptilolite, respectively, from ARD of pH 3.3. Removal of metals from the loaded clinoptilolite by back-flushing was found to depend on the pH, with an optimum pH range for extraction of 2.5 to 4.0 for a contact time of one hour. The rank of desorption effectiveness was EDTA > NaCl > NaNO3 > NaOAC > NaHCO3 > Na2CO3 > NaOH > Ca(OH)2. A novel process involving cyclic adsorption on clinoptilolite followed by regeneration of the sorbent by desorption is examined for the removal of heavy metals from acid rock drainage. Experimental results show that the adsorption of zinc and copper depends on the pH and on external mass transfer. Desorption is assisted by adding NaCl to the water. A slurry bubble column was able to significantly reduce the time required for both adsorption and desorption in batch tests. XRD analysis indicated

  13. Ensaios estáticos e cinéticos para a prevenção da geração de drenagem ácida de minas da mineração de carvão com escória de aciaria Static and kinetic tests to prevent the generation of acid mine drainage from coal mining with steel slag

    Luciana Angelita Machado

    2008-09-01

    Full Text Available A Drenagem Ácida de Mina (DAM é proveniente da oxidação natural de materiais sulfetados quando em contato com o ar e com a água. Esse problema atinge, em alto grau, a mineração de carvão. Uma das tecnologias de prevenção da geração da DAM consiste no método de aditivos alcalinos. Assim, o objetivo do presente trabalho foi avaliar, em estudos de laboratório, o controle da DAM pela mistura de um rejeito de carvão com uma escória do setor siderúrgico. O trabalho incluiu a coleta de uma amostra de rejeito de carvão de uma mineração de carvão e de uma amostra de escória de uma usina siderúrgica semi-integrada, ambas situadas no Estado do Rio Grande do Sul. Determinaram-se o potencial de geração de acidez e o potencial de neutralização dos materiais pelo método de contabilização de ácidos e bases. Após, realizaram-se ensaios cinéticos em células úmidas pelo Método ASTM D 5744-96. Os resultados demonstram que o rejeito de carvão gera DAM. Contudo os problemas ambientais podem ser em grande parte resolvidos pela mistura do rejeito com a escória em uma proporção de 4,8:1. Os ensaios cinéticos demonstram que, nessa condição, ocorre um aumento do pH e uma redução na liberação de acidez, metais e sulfatos na água lixiviada. Desta forma, foi demonstrado que a disposição conjunta de escória de aciaria com rejeito de carvão é uma alternativa viável para o controle da geração de DAM em minerações de carvão.The Acid Mine Drainage (AMD is the result of the natural oxidation of sulphide minerals when exposed to the combined action of water and oxygen. One of the technologies to prevent the AMD consists in the alkaline additive method. Thus, the aim of this work was to study, at laboratory scale, the DAM control by blending coal waste with a metallurgical slag. A coal-tailing sample was collected from a coal mine and the slag was obtained from a semi-integrated steel plant, both located in Rio Grande do Sul

  14. Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage

    Maria Mäkitalo

    2014-04-01

    Full Text Available Using alternative materials such as residual products from other industries to mitigate the negative effects of acid rock drainage would simultaneously solve two environmental problems. The main residual product still landfilled by sulphate paper mills is the alkaline material green liquor dregs (GLD. A physical, mineralogical and chemical characterization of four batches of GLD was carried out to evaluate the potential to use it as a sealing layer in the construction of dry covers on sulphide-bearing mine waste. GLD has relatively low hydraulic conductivity (10−8 to 10−9 m/s, a high water retention capacity (WRC and small particle size. Whilst the chemical and mineralogical composition varied between the different batches, these variations were not reflected in properties such as hydraulic conductivity and WRC. Due to relatively low trace element concentrations, leaching of contaminants from the GLD is not a concern for the environment. However, GLD is a sticky material, difficult to apply on mine waste deposits and the shear strength is insufficient for engineering applications. Therefore, improving the mechanical properties is necessary. In addition, GLD has a high buffering capacity indicating that it could act as an alkaline barrier. Once engineering technicalities have been overcome, the long-term effectiveness of GLD should be studied, especially the effect of aging and how the sealing layer would be engineered in respect to topography and climatic conditions.

  15. Characterization of the sulfate-reducing bacterial population in sediments of acid mining lakes

    With respect to remediation of acid mine drainage (AMD), concomitant alteration of redox conditions, formation of metal sulfides and alkalinity generation are of special interest. The majority of lakes formed in the Lusatian lignite mining district bear waters of low pH and high ionic strength. For several of these acid mining lakes, sulfate-reducing activities have been demonstrated. The aim of our study was to find out which bacteria are responsible for these activities, whether these SRB exhibit special traits to thrive under extreme conditions, and whether the population differed from those inhabiting freshwater and marine environments. For this purpose we estimated the most probable number (MPN) of culturable SRB in surface sediments of three mining lakes (ML) and obtained isolates from the same sites. The strains were characterised physiologically and phylogenetically. (orig.)

  16. Acid rock drainage and rock weathering in Antarctica: important sources for iron cycling in the Southern Ocean.

    Dold, B; Gonzalez-Toril, E; Aguilera, A; Lopez-Pamo, E; Cisternas, M E; Bucchi, F; Amils, R

    2013-06-18

    Here we describe biogeochemical processes that lead to the generation of acid rock drainage (ARD) and rock weathering on the Antarctic landmass and describe why they are important sources of iron into the Antarctic Ocean. During three expeditions, 2009-2011, we examined three sites on the South Shetland Islands in Antarctica. Two of them displayed intensive sulfide mineralization and generated acidic (pH 3.2-4.5), iron-rich drainage waters (up to 1.78 mM Fe), which infiltrated as groundwater (as Fe(2+)) and as superficial runoff (as Fe(3+)) into the sea, the latter with the formation of schwertmannite in the sea-ice. The formation of ARD in the Antarctic was catalyzed by acid mine drainage microorganisms found in cold climates, including Acidithiobacillus ferrivorans and Thiobacillus plumbophilus. The dissolved iron (DFe) flux from rock weathering (nonmineralized control site) was calculated to be 0.45 × 10(9) g DFe yr(-1) for the nowadays 5468 km of ice-free Antarctic rock coastline which is of the same order of magnitude as glacial or aeolian input to the Southern Ocean. Additionally, the two ARD sites alone liberate 0.026 and 0.057 × 10(9) g DFe yr(-1) as point sources to the sea. The increased iron input correlates with increased phytoplankton production close to the source. This might even be enhanced in the future by a global warming scenario, and could be a process counterbalancing global warming. PMID:23682976

  17. Isotopic evidence of enhanced carbonate dissolution at a coal mine drainage site in Allegheny County, Pennsylvania, USA

    Sharma, Shikha; Sack, Andrea; Adams, James P.; Vesper, Dorothy; J Capo, Rosemary C.; Hartsock, Angela; Edenborn, Harry M.

    2013-01-01

    Stable isotopes were used to determine the sources and fate of dissolved inorganic C (DIC) in the circumneutral pH drainage from an abandoned bituminous coal mine in western Pennsylvania. The C isotope signatures of DIC (δ{sup 13}C{sub DIC}) were intermediate between local carbonate and organic C sources, but were higher than those of contemporaneous Pennsylvanian age groundwaters in the region. This suggests a significant contribution of C enriched in {sup 13}C due to enhanced carbonate dissolution associated with the release of H{sub 2}SO{sub 4} from pyrite oxidation. The Sr isotopic signature of the drainage was similar to other regional mine waters associated with the same coal seam and reflected contributions from limestone dissolution and cation exchange with clay minerals. The relatively high δ{sup 34}S{sub SO4} and δ{sup 18}O{sub SO4} isotopic signatures of the mine drainage and the presence of presumptive SO{sub 4}-reducing bacteria suggest that SO{sub 4} reduction activity also contributes C depleted in {sup 13}C isotope to the total DIC pool. With distance downstream from the mine portal, C isotope signatures in the drainage increased, accompanied by decreased total DIC concentrations and increased pH. These data are consistent with H{sub 2}SO{sub 4} dissolution of carbonate rocks, enhanced by cation exchange, and C release to the atmosphere via CO{sub 2} outgassing.

  18. Treatment of mine drainage generated by lead-zinc concentration plant

    曾科; 覃文庆; 焦芬; 何名飞; 孔令强

    2014-01-01

    The purification efficiency in the treatment of the mine drainage generated by the mineral processing industry in Mengzi, Yunnan Project, China, was investigated, and the influences of the treated drainage on the mineral electrodes’ electrochemical behaviors were tested. Experiments with different doses of polyacrylamide (PAM) and polymeric ferric sulfate (PFS) at different pH values were carried out, and the advanced purification by activated carbon (AC) was conducted. Compared with PFS, the better coagulant for removal efficiency is PAM, under the optimal conditions, the removals of Pb2+, Zn2+, Cu2+and COD reduction from solution were 94.8%, 79.9%, 87.6% and 85%, respectively. In the advanced purification, the particle size of activated carbon and agitation time played important roles in the removal efficiency. Each pollute concentration could meet the emission standard of pollutants for lead and zinc industry (GB25466-2010). The wastewater without treatment affected galena and sphalerite electrochemical behaviors greatly, after treatment by the technology, the effects disappeared, which proved the reliability of the technology for wastewater treatment.

  19. Uranium recovery and uranium remove from acid mine waters by ion exchange resin

    Ion exchange using resins is one of few processes capable of reducing contaminants in effluents to very low levels according to environmental legislation. In this study the process was used to remove and recovery uranium from acid mine waters at Pocos de Caldas-MG Uranium Mining and Milling Plant. The presence of pyrite in the waste rock piles, resulting acid drainage with several pollutants. Including uranium ranging from 6 to 14 mg/l, as sulfate complex, that can be removed by an anionic exchanger. Studies of uranium sorption without treatment, and with lime pretreatment of water to precipitate the iron and recovery uranium as commercial product, are presented. Uranium elution was done with NaCl solutions. Saline concentration and retention time were the parameters studied. the uranium decontaminations level in the effluents from acid mine water was 94%. (author)

  20. Arsenic mobility in mildly alkaline drainage from an orogenic lode gold deposit, Bralorne mine, British Columbia

    Highlights: • As concentrations in flooded anoxic mine workings in range of 6000 μg/L. • Sorbed As released in workings by reductive dissolution of accumulated HFO. • As concentrations in portal effluent in range of 3000 μg/L. • Limited natural attenuation of As due to high pH and the lack of Fe sorbent. • Partitioning of As in effluent described by a field-scale distribution coefficient. - Abstract: The historical (1932–1971) Bralorne mine produced over 87 million grams of Au from an archetypal orogenic lode gold deposit in southwest British Columbia. High concentrations of As in mine drainage, however, represent an on-going environmental concern prompting a detailed study of effluent chemistry. The discharge rate at the mine portal was monitored continuously over a fourteen-month period during which effluent samples were collected on a quasi-weekly basis. Water samples were also collected on synoptic surveys of the adit between the portal and the main source of flow in the flooded workings. Total concentrations of As in the mildly alkaline (pH = 8.7) portal drainage average 3034 μg/L whereas at the source they average 5898 μg/L. As emergent waters from the flooded workings flow toward the portal, their dissolved oxygen content and pH increase from 0 to 10 mg/L and from 7.7 to 9, respectively. Near the emergence point, dissolved Fe precipitates rapidly, sorbing both As(III) and As(V). With increasing distance from the emergence point, dissolved As(III) concentrations drop to detection limits through sorption on hydrous ferric oxide and through oxidation to As(V). Concentrations of dissolved As(V), on the other hand, increase and stabilize, reflecting lower sorption at higher pH and the lack of available sorbent. Nonetheless, based on synoptic surveys, approximately 35% of the source As load is sequestered in the adit resulting in As sediment concentrations averaging 8.5 wt%. The remaining average As load of 1.34 kg/d is discharged from the portal

  1. Acid leaching of uranium present in a residue from mining industry

    The acid mine drainage is one of the most important environmental problems associated with mining of ores containing sulfides. The treatment of these acid effluents, which contains high concentrations of dissolved metals and anions, is generally by liming. The wastes generated in the liming process may present significant toxicity and their storage in inappropriate places waiting for treatment is a common issue that requires solution. Osamu Utsumi Mine located in the city of Caldas, Minas Gerais, has been facing this problem. The residue of this mine consists of an alkaline sludge generated from the neutralization of the pH of acid mine drainage and is rich in various metals, including uranium. The main concern is the long term stability of this residue, which is in permanent contact with the acid water in the open pit. The recovery of uranium by hydrometallurgical techniques, such as acid leaching, can be a viable alternative on the reuse of this material. This study aimed at establishing a specific leaching process for the recovery of uranium present in the sludge from Caldas uranium mine. Some parameters such as solid/liquid ratio (0.09 to 0.17), time of leaching (1 to 24 hours) and concentration of sulfuric acid (pH from 0 to 3.0) were assessed. The results showed that it is possible to extract 100% of uranium present in the sludge. The concentration of U3O8 in the residue was 0.25%, similar to the content of the vein ores which is around 0.20% to 1.0%. The best experimental leaching condition is solid/liquid ratio of 0.17, pH 1.0 and 2 hours of reaction at room temperature (25 deg C). The content of uranium in the liquor is around 440 mgL-1. The recovery of the uranium from the liquor is under investigation by ionic exchange. (author)

  2. Acid leaching of uranium present in a residue from mining industry

    Braulio, Walace S.; Ladeira, Ana C.Q. [Center for Development of Nuclear Technology (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Dept. of Mineral Technology

    2011-07-01

    The acid mine drainage is one of the most important environmental problems associated with mining of ores containing sulfides. The treatment of these acid effluents, which contains high concentrations of dissolved metals and anions, is generally by liming. The wastes generated in the liming process may present significant toxicity and their storage in inappropriate places waiting for treatment is a common issue that requires solution. Osamu Utsumi Mine located in the city of Caldas, Minas Gerais, has been facing this problem. The residue of this mine consists of an alkaline sludge generated from the neutralization of the pH of acid mine drainage and is rich in various metals, including uranium. The main concern is the long term stability of this residue, which is in permanent contact with the acid water in the open pit. The recovery of uranium by hydrometallurgical techniques, such as acid leaching, can be a viable alternative on the reuse of this material. This study aimed at establishing a specific leaching process for the recovery of uranium present in the sludge from Caldas uranium mine. Some parameters such as solid/liquid ratio (0.09 to 0.17), time of leaching (1 to 24 hours) and concentration of sulfuric acid (pH from 0 to 3.0) were assessed. The results showed that it is possible to extract 100% of uranium present in the sludge. The concentration of U{sub 3}O{sub 8} in the residue was 0.25%, similar to the content of the vein ores which is around 0.20% to 1.0%. The best experimental leaching condition is solid/liquid ratio of 0.17, pH 1.0 and 2 hours of reaction at room temperature (25 deg C). The content of uranium in the liquor is around 440 mgL{sup -1}. The recovery of the uranium from the liquor is under investigation by ionic exchange. (author)

  3. Coal acid mine drainage treatment using cement kiln dust

    Edgar Alberto Martínez

    2014-01-01

    Full Text Available Los sulfuros están presentes en distintas rocas. Durante las actividades mineras y el proceso de remoción de sulfuros se pueden producir Drenajes Ácidos de Minería (DAM, con iones de sulfato (SO4-2. Los DAMs son fuente de polución en las actividades mineras y en Colombia su descarga en los cuerpos de agua debe cumplir las regulaciones nacionales (pH entre 5 y 9. Polvo de horno cementero (CKD, con carbonato de calcio principalmente, de una planta de Cementos Argos S.A. fue usado para neutralizar un DAM generado en la biodesulfurización de carbón. Los DAMs neutralizados tuvieron pHs entre 7,72 y 8,05 y la eliminación de sulfatos entre 67% a 70%. El precipitado se secó y analizó para determinar su composición química y mineralógica. Se encontró humedad entre 69% y 81%; yeso con un 50% de pureza aproximadamente y carbonato de calcio. Esta composición lo hace adecuado para uso en la producción de cemento.

  4. The monitoring system of the pipeline safety of the coal mine gas drainage based on the optic fiber sensing technology

    Li, Yan-fang; Wei, Yubin; Zhang, Tingting; Zhao, Yanjie; Lv, Lei; Liu, Tong-yu

    2013-09-01

    Based on the technology of the spectrum absorption and the FBG, the monitoring system realize on line detection of the concentration of methane and oxygen, the temperature and the pressure of the gas in pipeline, and in order to improve the accuracy of the gas detection, we induce the compensation to the gas concentration using the data of the temperature and the pressure. In order to have a effective utilization of the methane in the coal mine gas drainage system, we have to have a accurate measurements of the concentration, the temperature and the pressure of the gas in pipeline. At the same time the dynamic monitoring of the concentration of Oxygen is a sign of the leakage of the pump. This paper gave some data detected in the field of the coal mine gas drainage system.

  5. Isolation and characterization of bacteria on the drainage water from Ratones mine and its behaviour on pyrite

    This paper describes some of the studies made about iron and sulfur oxidizing bacteria on the drainage water from Ratones mine. Different liquid and solid media were utilized as well as some energy sources, ferrous sulphate, thiosulfate and sulfur. Some experiment were al so realized on museum grade pyrite aimed at determining the possibilities of applying the mentioned bacteria on the leaching of pyrite and subsequently on the leaching of uranium ores. (Author) 27 refs

  6. Element determination in natural biofilms of mine drainage water by total reflection X-ray fluorescence spectrometry

    Human impacts like mining activities lead to higher element concentration in surface waters. For different pollution levels, the consequences for aquatic organisms are not yet investigated in detail. Therefore, the aim of this investigation is to determine the influence of mining affected surface waters on biofilms. Elements like heavy metals can be absorbed on cell walls and on polymeric substances or enter the cytoplasm of the cells. Thus, they are important for the optimization of industrial biotechnological processes and the environmental biotechnology. Beyond this, biofilms can also play an important role in wastewater treatment processes and serve as bioindicators in the aquatic environment. The presented total reflection X-ray fluorescence spectroscopic investigation was performed to compare the element accumulation behavior of biofilms grown on natural or on artificial materials of drainage water affected by former copper mining activities. A high salt and heavy metal pollution is characteristic for the drainage water. For an assessment of these results, samples from stream Schlenze upstream the confluence with the drainage water, a small tributary of the Saale River in central Germany, were analyzed, too

  7. Element determination in natural biofilms of mine drainage water by total reflection X-ray fluorescence spectrometry

    Mages, Margarete; von Tümpling, Wolf; van der Veen, Andrea; Baborowski, Martina

    2006-11-01

    Human impacts like mining activities lead to higher element concentration in surface waters. For different pollution levels, the consequences for aquatic organisms are not yet investigated in detail. Therefore, the aim of this investigation is to determine the influence of mining affected surface waters on biofilms. Elements like heavy metals can be absorbed on cell walls and on polymeric substances or enter the cytoplasm of the cells. Thus, they are important for the optimization of industrial biotechnological processes and the environmental biotechnology. Beyond this, biofilms can also play an important role in wastewater treatment processes and serve as bioindicators in the aquatic environment. The presented total reflection X-ray fluorescence spectroscopic investigation was performed to compare the element accumulation behavior of biofilms grown on natural or on artificial materials of drainage water affected by former copper mining activities. A high salt and heavy metal pollution is characteristic for the drainage water. For an assessment of these results, samples from stream Schlenze upstream the confluence with the drainage water, a small tributary of the Saale River in central Germany, were analyzed, too.

  8. Trace metal mobilization from oil sands froth treatment thickened tailings exhibiting acid rock drainage.

    Kuznetsova, Alsu; Kuznetsov, Petr; Foght, Julia M; Siddique, Tariq

    2016-11-15

    Froth treatment thickened tailings (TT) are a waste product of bitumen extraction from surface-mined oil sands ores. When incubated in a laboratory under simulated moist oxic environmental conditions for ~450d, two different types of TT (TT1 and TT2) exhibited the potential to generate acid rock drainage (ARD) by producing acid leachate after 250 and 50d, respectively. We report here the release of toxic metals from TT via ARD, which could pose an environmental threat if oil sands TT deposits are not properly managed. Trace metal concentrations in leachate samples collected periodically revealed that Mn and Sr were released immediately even before the onset of ARD. Spikes in Co and Ni concentrations were observed both pre-ARD and during active ARD, particularly in TT1. For most elements measured (Fe, Cr, V, As, Cu, Pb, Zn, Cd, and Se), leaching was associated with ARD production. Though equivalent acidification (pH2) was achieved in leachate from both TT types, greater metal release was observed from TT2 where concentrations reached 10,000ppb for Ni, 5000ppb for Co, 3000ppb for As, 2000ppb for V, and 1000ppb for Cr. Generally, metal concentrations decreased in leachate with time during ARD and became negligible by the end of incubation (~450d) despite appreciable metals remaining in the leached TT. These results suggest that using TT for land reclamation purposes or surface deposition for volume reduction may unfavorably impact the environment, and warrants application of appropriate strategies for management of pyrite-enriched oil sands tailings streams. PMID:27443453

  9. Amendment of an acid mine soil with compost and polyacrylate polymers enhances enzymatic activities but may change the distribution of plant species

    de Varennes, Amarilis; Queda, Cristina Cunha; Guiwei, Qu

    2009-01-01

    Many soils derived from pyrite mines spoils are acidic, poor in organic matter and plant nutrients, contaminated with trace elements, and support only sparse vegetation. The establishment of a plant cover is essential to decrease erosion and the contamination of water bodies with acid drainage containing large concentrations of trace elements. We tested the application of compost and polyacrylate polymers to promote the growth of indigenous plant species present in the mine area. Soil t...

  10. The effect of limestone treatments on the rate of acid generation from pyritic mine gangue.

    Burt, R A; Caruccio, F T

    1986-09-01

    Surface water enters the Haile Gold Mine, Lancaster County, South Carolina by means of a small stream and is ponded behind a dam and in an abandoned pit. This water is affected by acidic drainage. In spite of the large exposures of potentially acid producing pyritic rock, the flux of acid to the water is relatively low. Nevertheless, the resulting pH values of the mine water are low (around 3.5) due to negligible buffering capacity. In view of the observed low release of acidity, the potential for acid drainage abatement by limestone ameliorants appears feasible.This study investigated the effects of limestone treatment on acid generation rates of the Haile mine pyritic rocks through a series of leaching experiments. Below a critical alkalinity threshold value, solutions of dissolved limestone were found consistently to accelerate the rate of pyrite oxidation by varying degrees. The oxidation rates were further accelerated by admixing solid limestone with the pyritic rock. However, after a period of about a month, the pyrite oxidation rate of the admixed samples declined to a level lower than that of untreated pyrite. Leachates produced by the pyrite and limestone mixtures contained little if any iron. Further, in the mixtures, an alteration of the pyrite surface was apparent.The observed behaviour of the treated pyrite appears to be related to the immersion of the pyrite grains within a high alkalinity/high pH environment. The high pH increases the rate of oxidation of ferrous iron which results in a higher concentration of ferric iron at the pyrite surface. This, in turn, increases the rate of pyrite oxidation. Above a threshold alkalinity value, the precipitation of hydrous iron oxides at the pyrite surface eventually outpaces acid generation and coats the pyrite surface, retarding the rate of pyrite oxidation. PMID:24214013

  11. Efficient inhibition of heavy metal release from mine tailings against acid rain exposure by triethylenetetramine intercalated montmorillonite (TETA-Mt).

    Gong, Beini; Wu, Pingxiao; Huang, Zhujian; Li, Yuanyuan; Yang, Shanshan; Dang, Zhi; Ruan, Bo; Kang, Chunxi

    2016-11-15

    The potential application of triethylenetetramine intercalated montmorillonite (TETA-Mt) in mine tailings treatment and AMD (acid mine drainage) remediation was investigated with batch experiments. The structural and morphological characteristics of TETA-Mt were analyzed with XRD, FTIR, DTG-TG and SEM. The inhibition efficiencies of TETA-Mt against heavy metal release from mine tailings when exposed to acid rain leaching was examined and compared with that of triethylenetetramine (TETA) and Mt. Results showed that the overall inhibition by TETA-Mt surpassed that by TETA or Mt for various heavy metal ions over an acid rain pH range of 3-5.6 and a temperature range of 25-40°C. When mine tailings were exposed to acid rain of pH 4.8 (the average rain pH of the mining site where the mine tailings were from), TETA-Mt achieved an inhibition efficiency of over 90% for Cu(2+), Zn(2+), Cd(2+) and Mn(2+) release, and 70% for Pb(2+) at 25°C. It was shown that TETA-Mt has a strong buffering capacity. Moreover, TETA-Mt was able to adsorb heavy metal ions and the adsorption process was fast, suggesting that coordination was mainly responsible. These results showed the potential of TETA-Mt in AMD mitigation, especially in acid rain affected mining area. PMID:27450331

  12. Impact assessment of mine drainage water and municipal wastewater on the surface water in the vicinity of Bor

    Gardić Vojka R.

    2015-01-01

    impact on the environment. The study included the following sources of pollution: mining waste and drainage water originating from the active mine (Bor pit , field 1 Krivelj large tailings, flotation tailings in Bor RTH, metallurgical water, as well as the drainage water from the flotation tailings, which are no longer in operation (field 2 flotation tailings Great Krivelj, drainage water from the old Bor flotation tailings, the old inactive landfill mine gangue (Saraka landfill, Veliki planir - tailings from the old Bor mine, landfill mine gangue from mine RTH and the city - urban waste water, which are discharged without treatment directly into the watercourse Bor River. Wastewater directly pollute Bor River and Krivalj River.

  13. Organic carbon amendments for passive in situ treatment of mine drainage: Field experiments

    Highlights: → Organic carbon amendments can support passive treatment of mine drainage. → Decreased transport of sulfide-oxidation products under sulfate-reducing conditions. → Treatment effectiveness dependent on organic carbon source and amendment rate. - Abstract: A field-scale experiment was conducted to evaluate various organic C sources as amendments for passive treatment of tailings pore water. Varied mixtures of peat, spent-brewing grain (SBG) and municipal biosolids (MB) were assessed for the potential to promote dissimilatory sulfate reduction (DSR) and metal-sulfide precipitation. Five amended cells and one control were constructed in the vadose zone of a sulfide- and carbonate-rich tailings deposit, and the geochemistry, microbiology and mineralogy were monitored for 4 a. Increases in pore-water concentrations of dissolved organic C (DOC) and decreases in aqueous SO4 concentrations of >2500 mg L-1 were observed in cells amended with peat + SBG and peat + SBG + MB. Removal of SO4 was accompanied by shifts in δ34S-SO4 values of >+30 per mille, undersaturation of pore water with respect to gypsum [CaSO4.2H2O], and increased populations of SO4-reducing bacteria (SRB). Decreases in aqueous concentrations of Zn, Mn, Ni, Sb and Tl were observed for these cells relative to the control. Organic C introduction also supported growth of Fe-reducing bacteria (IRB) and increases in Fe and As concentrations. Enhanced Fe and As mobility occurred in all cells; however, maximum concentrations were observed in cells amended with MB. Subsequent decreases in Fe and As concentrations were attributed to DSR and metal-sulfide precipitation. The common presence of secondary Zn-S and Fe-S phases was observed by field emission-scanning electron microscopy (FE-SEM) and energy dispersive X-ray (EDS) spectroscopy. Selective extractions indicated that large decreases in water-soluble SO4 occurred in cells that supported DSR. Furthermore, amendments that supported DSR generally

  14. GIS-based environmental database for assessing the mine pollution : a case study of an abandoned mine site in Morocco

    Khalil, A.; Hanich, L.; Hakkou, R.; Lepage, Michel

    2014-01-01

    Morocco with important mining activities is increasingly concerned about impacts of mining on the environment. In Morocco, there are approximately 200 abandoned mine sites which vary from small scale underground mines to large scale open-pit mines. Some of these mines, with reactive tailings and waste rocks, are problematic. Indeed, Acid Mine Drainage (AMD) pollution from abandoned mines is responsible for soil and water contamination, land resources degradation, changes in landscapes, habita...

  15. Removal of radionuclides from acid mine waters by retention on adsorbing materials

    This study proposes a method for decontamination of acid drainage water from a uranium mine, as an alternative process to lime treatment. The research embodied the recovery of uranium with an ion-exchange resin, treatment of effluent resin with lime, or with inorganic adsorbents and biosorbents. The uranium decontamination level using the resin process was 94% and allowed the recovery of this element as a commercial product. Among the inorganic adsorbents studied, phosphogypsum was effective for 226Ra, 228Ra, and 210Pb removal. Among the biosorbents, Sargassum sp. was superior in relation to its specific capacity to accumulate and remove 226Ra. (author)

  16. Multibiomarker toxicity characterization of uranium mine drainages to the fish Carassius auratus.

    Bessa, M L; Antunes, S C; Pereira, R; Gonçalves, F J M; Nunes, B

    2016-07-01

    The release of acidic effluents, naturally enriched in metals and radionuclides, is the main legacy of uranium mines. Generally, metals dissolved by these acidic effluents can cause significant alterations in exposed organisms, with distinct toxicological outcomes. In this study, 72 individuals of the freshwater fish species Carassius auratus were exposed in situ for different periods (8, 16, 24, and 48 h) to water from a pond (treatment pond (TP)) with a chemically treated effluent and a reference pond (PRP), in the vicinity of the Cunha Baixa uranium mine (Portugal). Comparing the water of the two ponds, the PRP pond was characterized by higher pH and oxygen values and lower conductivity and hardness values. Regarding total metal concentrations, among others, magnesium (56,000 μg/L), sodium (17,400 μg/L), zinc (86 μg/L), manganese (6340 μg/L), and uranium (1380 μg/L) concentrations in the TP pond were above the values obtained for the PRP pond. The values of manganese and uranium exceeded the values of quality criteria established for surface waters for cyprinids and for irrigation purposes. After exposure to pond water, significant differences were recorded for several biomarkers: (i) between ponds for acetylcholinesterase (AChE) with higher activities for animals from the PRP and glutathione-S-transferase (GST) activities that were particularly enhanced in animals from the TP pond; (ii) between ponds and exposure periods for lactate dehydrogenase (LDH) activity, since organisms from PRP pond presented always higher values than those from the TP pond, and among these, organisms exposed for the longer period presented a further depression in LDH activity; and (iii) between exposure periods for erythrocyte micronucleus. GSTs and LDH were the most sensitive biomarkers within the timeframe of the in situ assay performed. Despite the alleged efficacy of the chemical treatment (evidenced by a significantly lower pH), some metals persisted in the treated

  17. Comparison of microbial communities in three different mine drainages and their bioleaching efficiencies to low grade of chalcopyrite

    YIN Hua-qun; QIU Guan-zhou; WANG Dian-zuo; CAO Lin-hui; DAI Zhi-min; WANG Jie-wei; LIU Xue-duan

    2007-01-01

    Microbial community diversities in the drainage from three mines (Dexing Copper Mine, Qibaoshan Copper Mine and Yaogangxian Tungsten Mine, China) were analyzed using 16S rDNA PCR-RFLP approach. The efficiencies of chalcopyrite bioleaching were compared using enrichment of the three cultures. Phylogenetic analysis indicates that the dominant microorganisms are clustered with the Proteobacteria, the remaining is affiliated with Nitrospira, Acidobacteria and Actinobacteria.At the genus level, Acidithiobacillus is the dominant group in both YTW and QBS samples, while Spingomonas is dominant in YGX sample. Moreover, the principal component analysis (PCA) reveals that QBS and YTW have similar geochemical character and microbial communities. The results also show that pH value and tungsten concentration play a key role in microbial community distribution and relative abundance. The bioleaching efficiency of the enrichment cultures from YTW and QBS is similar. After 15 d,the bioleaching rates of low grade chalcopyrite (0.99%) are both up to 99.5% when using 10 g/L pulp density due to the similar microbial composition of YTW and QBS. Moreover, the leaching efficiencies of enrichment cultures containing multiple bioleaching microorganisms are higher than that of pure culture Acidithiobacillus ferrooxidans.

  18. Zn(Ⅱ)对生物质碳源处理酸性矿山排水中厌氧微生物活性影响%Effect of Zn(II) on Microbial Activity in Anaerobic Acid Mine Drainage Treatment System with Biomass as Carbon Source

    黎少杰; 陈天虎; 周跃飞; 岳正波; 金杰; 刘畅

    2012-01-01

    通过厌氧批实验的方法,探讨了在硫酸盐还原菌(SRB)法处理模拟酸性矿山排水(AMD)的过程中,以油菜秸秆为碳源时,Zn2+浓度对SRB活性的影响.结果表明,在60 d实验中,以油菜秸秆为碳源时,当Zn2+初始浓度在73.7~196.8 mg·L-1范围时,SRB具有良好活性,实验结束时,pH从初始的5.0上升至中性范围,硫酸根还原率达到96%以上,同时Zn2+浓度降至0.05 mg·L-1以下.Tessier固体形态分类、场发射扫描电镜(FE-SEM)和X射线衍射仪(XRD)分析发现,Zn以有机物及硫化物的形态被固定,其中硫化物主要为闪锌矿(ZnS).当Zn2+初始浓度为262.97 mg·L-1时,SRB的活性受到强烈的抑制,实验结束时,pH从初始的5.0降至4.0左右,硫酸根还原率只有27%,Zn2+维持在较高浓度范围(25 mg·L-1).油菜秸秆可以作为SRB法长期处理AMD的缓释碳源, 能为微生物生长繁殖提供物质和能量; 秸秆的吸附性可降低Zn2+的生物毒性,使得SRB可以适应高浓度的Zn2+; SRB可以通过形成硫化物矿物的形式固定元素Zn.%In this study, with rape straw as carbon source, anaerobic batch experiments were executed to investigate the effect of Zn(Ⅱ) on the activity of sulphate reducing bacteria (SRB) in the microbial treatment of simulative acid mine drainage (AMD). The results showed that during the 60 experimental days, when initial Zn2+ concentrations were in the range of 73.7 to 196.8 mg·L-1, SRB had high culturalbility. At the end of these experiments, pH values rose from initial 5.0 to neutral, about 96% of sulphate was reduced and the concentrations of Zn2+ reduced to 0.05 mg·L-1. The results of Tessier sequential extraction, field emission scanning electron microscope(FE-SEM) and X-ray diffraction(XRD) showed that Zn was found to be fixed through forming organic and sulphide (mainly sphalerite) compounds. For the experiment with high Zn2+ concentration (262

  19. Bioaccumulation of metals in constructed wetlands used to treat acid drainage

    Constructed wetlands are being used extensively as a potential mitigation for acid drainage. However, removal of metals to meet compliance requirements has varied among wetlands, ranging from partial to total success. In addition, wetlands are sinks for contaminants found in acid drainage, and bioaccumulation of these contaminants to levels that would adversely affect the food web is of growing concern. The primary objective of this project was to determine whether bioaccumulation of metals occurs in wetlands constructed for treatment of acid drainage. Water, sediment, plant and benthos samples were collected from two wetlands constructed by the Tennessee Valley Authority and a natural wetland in the spring and fall of 1992, and metal concentrations were determined. One of the constructed wetlands, Impoundment 1, has generally been in compliance for NPDES; the other, Widow's Creek, has never been in compliance. Preliminary results indicate similarities in sediment and plant metal concentrations between Impoundment 1 and the natural wetland and greater metal concentrations in the sediment and plants at Widow's Creek. Data also indicate that Mn, Zn, Cu, Ni, and Cr are being accumulated in the plants at each wetland. However, accumulation of metals by these plants probably accounts for only a small percentage of the removal of the annual metal load supplied to each wetland. Bioaccumulation of metals in the benthic organisms at each wetland is currently being investigated

  20. Characterization of microorganisms in the acidic mine water of the former uranium mine Koenigstein

    The thesis on the characterization of microorganisms in the acidic mine water of the former uranium mine Koenigstein covers the following issues: Introduction: (1) Environmental rehabilitation of the uranium mine by the Wismut GmbH, microorganisms in the acidic mine waters, influence of microorganisms on the mobility of metals and radionuclides, biofilms and their influence on the mobility of metals and radionuclides, biodiversity of the mine Koenigstein before flooding; (2) Scope of the work. (3) Materials and methods: Site characterization, biofilm systems, sampling of water and biofilms, sample transport and storage, chemical analysis, speciation diagrams, catalyzed reporter deposition fluorescence in-situ hybridization, quantitative microbiological methods, classical microbiological cultivation methods, molecular biological methods, bioinformatics - sequence analysis, statistics, optical microscopy, biofilms. (4) Results and discussion: chemo-physical parameters before and after flooding, quantification of microorganisms, characterization of prokaryotes, characterization of eukaryotes, biofilms.

  1. 大型矿井排水设备选型计算%Calculation and selection in drainage equipment for oversize coal mine

    乔淑云; 李德臣

    2014-01-01

    排水设备选型的优劣不仅直接影响矿井初期投资和运转费用,而且影响安全生产。根据现代化大型煤矿-红庆梁矿井正常涌水量及最大涌水量,给出了矿井排水设备选型与计算方法。通过计算水泵排水能力、管路阻力系数、工况点参数、排水管路壁厚、电耗,确定主排水设备和应急排水系统选型结果,为大型矿井的排水设备选型提供参考。%Selection of drainage equipment not only directly affect the merits of the initial mine investment and operating costs, but also affect the safety in production. The method of calculation and selection for main mine drainage equipment is given in this paper based on a new modern coal mine such as Hong Qing Liang mine that normal water gushing and the largest water inlfow. the selection results of determine the main drainage equipment and emergency drainage system provide a reference for a large mine drainage equipment selection by calculating the drainage capacity, pipeline drag coefifcient, pump operating conditions parameters, drain line wall thickness and power consumption.

  2. Proceedings of the 15. annual national meeting of the American Society for Surface Mining and Reclamation. Mining -- Gateway to the future

    The 124 papers of these proceedings are arranged under the following topical sections: Minerals education; Hydrology--Characterization and monitoring; Tailings--Reclamation; Reforestation; Mine drainage--Biogeochemical processes; Mine drainage--Treatment, general; Mine drainage--Passive treatment, wetlands; Mine drainage--Prediction and monitoring; Acid soils--Reclamation practices; Wildlife and fisheries habitat; Subsidence--Engineering practices and environmental effects; OSM acid forming materials mini workshops; RUSLE--Erosion prediction techniques on mined construction and reclaimed lands; IDNR wetlands technology transfer program; Mine planning and postmining land use; Vegetation establishment--Principles and practices; Vegetation establishment--Warm season grasses; Coal combustion by-products--General; Coal combustion by-products--Mine drainage treatment; and Prime farmland reclamation and mine soils management. Papers within scope have been processed separately for inclusion on the data base

  3. Manual of acid in situ leach uranium mining technology

    In situ leaching (ISL) technology recovers uranium using two alternative chemical leaching systems - acid and alkaline. This report brings together information from several technical disciplines that are an essential part of ISL technology. They include uranium geology, geohydrology, chemistry as well as reservoir engineering and process engineering. This report provides an extensive description of acid ISL uranium mining technology

  4. Effects of iron on arsenic speciation and redox chemistry in acid mine water

    Bednar, A.J.; Garbarino, J.R.; Ranville, J.F.; Wildeman, T.R.

    2005-01-01

    Concern about arsenic is increasing throughout the world, including areas of the United States. Elevated levels of arsenic above current drinking-water regulations in ground and surface water can be the result of purely natural phenomena, but often are due to anthropogenic activities, such as mining and agriculture. The current study correlates arsenic speciation in acid mine drainage and mining-influenced water with the important water-chemistry properties Eh, pH, and iron(III) concentration. The results show that arsenic speciation is generally in equilibrium with iron chemistry in low pH AMD, which is often not the case in other natural-water matrices. High pH mine waters and groundwater do not always hold to the redox predictions as well as low pH AMD samples. The oxidation and precipitation of oxyhydroxides deplete iron from some systems, and also affect arsenite and arsenate concentrations through sorption processes. ?? 2004 Elsevier B.V. All rights reserved.

  5. A sequential approach to control gas for the extraction of multi-gassy coal seams from traditional gas well drainage to mining-induced stress relief

    Highlights: • The gas reservoirs characteristics are measured and analyzed. • A sequential approach to control gas of multi-gassy coal seams is proposed. • The design of gas drainage wells has been improved. • The utilization ways of different concentrations of gas production are shown. - Abstract: As coal resources become exhausted in shallow mines, mining operations will inevitably progress from shallow depth to deep and gassy seams due to increased demands for more coal products. However, during the extraction process of deeper and gassier coal seams, new challenges to current gas control methods have emerged, these include the conflict between the coal mine safety and the economic benefits, the difficulties in reservoirs improvement, as well as the imbalance between pre-gas drainage, roadway development and coal mining. To solve these problems, a sequential approach is introduced in this paper. Three fundamental principles are proposed: the mining-induced stress relief effect of the first-mined coalbed should be sufficient to improve the permeability of the others; the coal resource of the first-mined seams must be abundant to guarantee the economic benefits; the arrangement of the vertical wells must fit the underground mining panel. Tunlan coal mine is taken as a typical example to demonstrate the effectiveness of this approach. The approach of integrating surface coalbed methane (CBM) exploitation with underground gas control technologies brings three major benefits: the improvement of underground coal mining safety, the implementation of CBM extraction, and the reduction of greenhouse gas emissions. This practice could be used as a valuable example for other coal mines having similar geological conditions