Processes Controlling Trace-Metal Transport in Surface Water Contaminated by Acid-Mine Drainage in the Ducktown Mining District, Tennessee

AbstractAcid mine drainage is the reaction of surface water with sub-surface water located on sulfur bearing rocks, resulting in sulfuric acid. These highly acidic conditions result in leaching of non-biodegradeable heavy metals from rock which then accumulate in flora, posing a significant environmental hazard. Hence, reliable, cost effective remediation techniques are continuously sought after by researchers. A range of materials were examined as adsorbents in the extraction of heavy metal ions from acid mine drainage (AMD). However, these materials generally have moderate to poor adsorption capacities. To address this problem, researchers have recently turned to nano-sized materials to enhance the surface area of the adsorbent when in contact with the heavy metal solution. Lately, there have been developments in studying the surface chemistry of nano-engineered materials during adsorption, which involved alterations in the physical and chemical make-up of nanomaterials. The resultant surface engineered nanomaterials have been proven to show rapid adsorption rates and remarkable adsorption capacities for removal of a wide range of heavy metal contaminants in AMD compared to the unmodified nanomaterials. A brief overview of zeolites as adsorbents and the developent of nanosorbents to modernly applied magnetic sorbents and ion imprinted polymers will be discussed. This work provides researchers with thorough insight into the adsorption mechanism and performance of nanosorbents, and finds common ground between the past, present and future of these versatile materials.

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Assessment of Impacts of Acid Mine Drainage on Surface Water Quality of Tweelopiespruit Micro-Catchment, Limpopo Basin

Water Quality ◽

10.5772/65810 ◽

2017 ◽

Cited By ~ 1

Author(s):

Bloodless Dzwairo ◽

Munyaradzi Mujuru

Keyword(s):

Water Quality ◽

Surface Water ◽

Acid Mine Drainage ◽

Mine Drainage ◽

Surface Water Quality ◽

Acid Mine

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Metal transport and remobilisation in a basin affected by acid mine drainage: the role of ochreous amorphous precipitates

Environmental Science and Pollution Research ◽

10.1007/s11356-017-9209-9 ◽

2017 ◽

Vol 24 (18) ◽

pp. 15735-15747 ◽

Cited By ~ 10

Author(s):

Sirio Consani ◽

Cristina Carbone ◽

Enrico Dinelli ◽

Tonci Balić-Žunić ◽

Laura Cutroneo ◽

...

Keyword(s):

Acid Mine Drainage ◽

Mine Drainage ◽

Metal Transport ◽

Acid Mine

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Trace Metal Adsorption onto an Acid Mine Drainage Iron(III) Oxy Hydroxy Sulfate

Environmental Science & Technology ◽

10.1021/es9704390 ◽

1998 ◽

Vol 32 (10) ◽

pp. 1361-1368 ◽

Cited By ~ 243

Author(s):

Jenny G. Webster ◽

Peter J. Swedlund ◽

Kerry S. Webster

Keyword(s):

Acid Mine Drainage ◽

Trace Metal ◽

Mine Drainage ◽

Metal Adsorption ◽

Acid Mine

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Mixotrophic Iron-Oxidizing Thiomonas Isolates from an Acid Mine Drainage-Affected Creek

Applied and Environmental Microbiology ◽

10.1128/aem.01424-20 ◽

2020 ◽

Vol 86 (24) ◽

Author(s):

Denise M. Akob ◽

Michelle Hallenbeck ◽

Felix Beulig ◽

Maria Fabisch ◽

Kirsten Küsel ◽

...

Keyword(s):

Acid Mine Drainage ◽

Mine Drainage ◽

Iron Oxidation ◽

Specific Gene ◽

Mining District ◽

Content Type ◽

Acid Mine ◽

Metal Precipitation ◽

Genetic Potential ◽

Fe Oxidation

ABSTRACT Natural attenuation of heavy metals occurs via coupled microbial iron cycling and metal precipitation in creeks impacted by acid mine drainage (AMD). Here, we describe the isolation, characterization, and genomic sequencing of two iron-oxidizing bacteria (FeOB) species: Thiomonas ferrovorans FB-6 and Thiomonas metallidurans FB-Cd, isolated from slightly acidic (pH 6.3), Fe-rich, AMD-impacted creek sediments. These strains precipitated amorphous iron oxides, lepidocrocite, goethite, and magnetite or maghemite and grew at a pH optimum of 5.5. While Thiomonas spp. are known as mixotrophic sulfur oxidizers and As oxidizers, the FB strains oxidized Fe, which suggests they can efficiently remove Fe and other metals via coprecipitation. Previous evidence for Thiomonas sp. Fe oxidation is largely ambiguous, possibly because of difficulty demonstrating Fe oxidation in heterotrophic/mixotrophic organisms. Therefore, we also conducted a genomic analysis to identify genetic mechanisms of Fe oxidation, other metal transformations, and additional adaptations, comparing the two FB strain genomes with 12 other Thiomonas genomes. The FB strains fall within a relatively novel group of Thiomonas strains that includes another strain (b6) with solid evidence of Fe oxidation. Most Thiomonas isolates, including the FB strains, have the putative iron oxidation gene cyc2, but only the two FB strains possess the putative Fe oxidase genes mtoAB. The two FB strain genomes contain the highest numbers of strain-specific gene clusters, greatly increasing the known Thiomonas genetic potential. Our results revealed that the FB strains are two distinct novel species of Thiomonas with the genetic potential for bioremediation of AMD via iron oxidation. IMPORTANCE As AMD moves through the environment, it impacts aquatic ecosystems, but at the same time, these ecosystems can naturally attenuate contaminated waters via acid neutralization and catalyzing metal precipitation. This is the case in the former Ronneburg uranium-mining district, where AMD impacts creek sediments. We isolated and characterized two iron-oxidizing Thiomonas species that are mildly acidophilic to neutrophilic and that have two genetic pathways for iron oxidation. These Thiomonas species are well positioned to naturally attenuate AMD as it discharges across the landscape.

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Physico-Chemical Influence of Surface Water Contaminated by Acid Mine Drainage on the Populations of Diatoms in Dams (Iberian Pyrite Belt, SW Spain)

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16224516 ◽

2019 ◽

Vol 16 (22) ◽

pp. 4516 ◽

Cited By ~ 2

Author(s):

Maria José Rivera ◽

Ana Teresa Luís ◽

José Antonio Grande ◽

Aguasanta Miguel Sarmiento ◽

José Miguel Dávila ◽

...

Keyword(s):

Surface Water ◽

Acid Mine Drainage ◽

Mine Drainage ◽

Iberian Pyrite Belt ◽

Early Spring ◽

Chemical Characteristics ◽

Acid Mine ◽

Physico Chemical ◽

Diatom Communities ◽

Chemical Conditions

Twenty-three water dams located in the Iberian Pyrite Belt were studied during March 2012 (early spring) in order to carry out an environmental assessment based on diatom communities and to define the relationships between these biological communities and the physico-chemical characteristics of the dam surface water. This is the first time that a diatom inventory has been done for dams affected by acid mine drainage (AMD) in the Spanish part of the Iberian Pyrite Belt (IPB). It was found that the pH was the main factor influencing the behaviour of the diatom communities. Then, using a dbRDA approach it was possible to organize the aggrupation of diatoms into four groups in response to the physico-chemical conditions of the ecosystem, especially pH: (1) Maris, Aac, Gos, Cmora (pH 2–3); (2) Andc, San, And, Dpin (pH 3–4.5); (3) Gran, Pleon, Oliv, Lagu, Chan, SilI, SilII, Joya, Gar, Agrio, Camp, Corum (pH 4.5–6); (4) Herr, Diq I, Diq II (pH 6–7). The obtained results confirmed the response of benthic diatom communities to changes in the physico-chemical characteristics of surface water, and helped to understand the role of diatoms as indicators of the degree of AMD contamination in those 23 dams. Special attention was given to those that have an acidophilic or acid-tolerant profile (pH 2–3 and pH 3–4.5) such as Pinnularia aljustrelica, Pinnularia acidophila, Pinnularia acoricola and Eunotia exigua, which are the two groups found in the most AMD contaminated dams.

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