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John V Headley - One of the best experts on this subject based on the ideXlab platform.
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novel materials for environmental remediation of Tailing Pond waters containing naphthenic acids
Process Safety and Environmental Protection, 2008Co-Authors: Mohamed H Mohamed, Lee D Wilson, John V Headley, Kerry M PeruAbstract:A nanofiltration strategy for Tailing Pond waters (TPWs) that utilizes cyclodextrin (CD)-based polymeric materials as supramolecular sorbents is proposed. Naphthenic acids (NAs) from the Athabasca TPWs are investigated as the target sorbate molecules. The sorption properties of several supramolecular porous materials were characterized using equilibrium sorption isotherms in aqueous solution wherein electrospray ionization mass spectrometry was used to monitor the concentration of NAs in aqueous solution. The characterization of the supramolecular sorbents was performed using 13 C NMR and IR spectroscopy, while nitrogen porosimetry was used to estimate their surface area and pore structure properties. Independent estimates of surface area were obtained using a chromophore dye adsorption method in aqueous solution. The sorption results for NAs in solution were compared between a commercially available standard; granular activated carbon (GAC) and three types of synthetic materials. The sorption capacities for GAC ranged from 100 to 160 mg NAs/g of material whereas the polymeric materials ranged from 20 to 30 mg NAs/g of material over the experimental conditions investigated. In general, differences in the sorption properties between GAC and the CDbased sorbents were observed and related to differences in the surface areas of the materials and the chemical nature of the sorbents. The CD-based supramolecular materials displayed sorption capacities ranging from 36.2 to 657 m 2 /g as compared to that for GAC (795 m2/g). © 2008 Published by Elsevier B.V. on behalf of The Institution of Chemical Engineers.
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in situ bioremediation of naphthenic acids contaminated Tailing Pond waters in the athabasca oil sands region demonstrated field studies and plausible options a review
Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 2005Co-Authors: E K Quagraine, H G Peterson, John V HeadleyAbstract:Currently, there are three industrial plants that recover oil from the lower Athabasca oil sands area, and there are plans in the future for several additional mines. The extraction procedures produce large volumes of slurry wastes contaminated with naphthenic acids (NAs). Because of a "zero discharge" policy the oil sands companies do not release any extraction wastes from their leases. The process-affected waters and fluid Tailings contaminated with NAs are contained on-site primarily in large settling Ponds. These fluid wastes from the Tailing Ponds can be acutely and chronically toxic to aquatic organisms, and NAs have been associated with this toxicity. The huge Tailings containment area must ultimately be reclaimed, and this is of major concern to the oil sands industry. Some reclamation options have been investigated by both pioneering industries (Syncrude Energy Inc. and Suncor Inc.) with mixed results. The bioremediation techniques have limited success to date in biodegrading NAs to levels below 19 mg/L. Some Tailing Pond waters have been stored for more than 10 years, and it appears that the remaining high molecular weight NAs are refractory to the natural biodegradation process in the Ponds. Some plausible options to further degrade the NAs in the Tailings Pond water include: bioaugmentation with bacteria selected to degrade the more refractory classes of NAs; the use of attachment materials such as clays to concentrate both the NA and the NA-degrading bacteria in their surfaces and/or pores; synergistic association between algae and bacteria consortia to promote efficient aerobic degradation; and biostimulation with nutrients to promote the growth and activity of the microorganisms.
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is biodegradation of bitumen a source of recalcitrant naphthenic acid mixtures in oil sands Tailing Pond waters
Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 2005Co-Authors: E K Quagraine, John V Headley, H G PetersonAbstract:Carboxylic acids are transient metabolites during the mineralization of petroleum hydrocarbons. Crude oils, however, vary in their proportion of the hydrocarbon components. Depending on structure, some carboxylic acid metabolites resist further biodegradation and persist in aquatic systems. During the extraction of oil sands bitumen, recalcitrant carboxylic acid mixtures, collectively referred to as naphthenic acids (NAs), are released into the wastewaters. These waters also contain unrecovered bitumen from the oil sands. The unextracted bitumen is often overlooked as a possible source of the petroleum acids. The present article discusses the literature data on the biotransformation of hydrocarbons in bitumen from oil sands to the corresPonding petroleum carboxylic acids. Some insight is given on the mechanism of the biodegradation process. The susceptibility to biodegradation is affected by differences in alicyclic carboxylic acids such as carbon chain length, chain branching, and the oddness or evenness of carbon chain containing the carboxylic group, positions where alkyl groups are substituted on the cyclic ring, geometrical isomerism, and number of cyclic rings.
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in situ bioremediation of naphthenic acids contaminated Tailing Pond waters in the athabasca oil sands region demonstrated field studies and plausible options a review
Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 2005Co-Authors: E K Quagraine, H G Peterson, John V HeadleyAbstract:Abstract Currently, there are three industrial plants that recover oil from the lower Athabasca oil sands area, and there are plans in the future for several additional mines. The extraction procedures produce large volumes of slurry wastes contaminated with naphthenic acids (NAs). Because of a “zero discharge” policy the oil sands companies do not release any extraction wastes from their leases. The process-affected waters and fluid Tailings contaminated with NAs are contained on-site primarily in large settling Ponds. These fluid wastes from the Tailing Ponds can be acutely and chronically toxic to aquatic organisms, and NAs have been associated with this toxicity. The huge Tailings containment area must ultimately be reclaimed, and this is of major concern to the oil sands industry. Some reclamation options have been investigated by both pioneering industries (Syncrude Energy Inc. and Suncor Inc.) with mixed results. The bioremediation techniques have limited success to date in biodegrading NAs to leve...
C Fernandezdelgado - One of the best experts on this subject based on the ideXlab platform.
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recolonization process and fish assemblage dynamics in the guadiamar river sw spain after the aznalcollar mine toxic spill
River Research and Applications, 2016Co-Authors: R J De Miguel, L Galvezbravo, Francisco J Olivapaterna, Luis Cayuela, C FernandezdelgadoAbstract:The Guadiamar River (SW Iberian Peninsula) received a major toxic spill (6 hm3) from a Tailing Pond in 1998 that defaunated 67 km of the main stem. Following early mud removal works, the fish assemblage was annually monitored at four affected sampling sites and one located in the upstream non-affected reach of the Guadiamar River as reference. Fish abundance and assemblage structure were analysed. Principal response curve was applied to assess the recovery trends and to identify the most influential species. A non-metric multidimensional scaling ordination and permutational multivariate analysis of variance were applied to evaluate changes in fish assemblage structure between sites and years. Overall, the affected reaches harboured fish within 2 years of the spill. Colonists arrived mainly from the upstream and downstream non-affected Guadiamar River reaches and, to a lesser extent, from three lateral tributaries. It is likely that the proximity, connectivity and environmental conditions of non-affected fish sources greatly influenced the recolonization process in each site. The structure of the fish community in the affected sites was initially similar to that in the unaffected reference stretch but changed dramatically with time, and each site followed its own trajectory. Currently, long-term threats such as mining leachates, urban sewage, agricultural pollution and exotic fish species expansion have probably exceeded the initial spill effect. This highlights the large effect of anthropogenic factors on freshwater ecosystem resilience, and the need to significantly reduce both pollution and exotic species if the affected reach of the Guadiamar River is to recover fully. Copyright © 2015 John Wiley & Sons, Ltd.
E K Quagraine - One of the best experts on this subject based on the ideXlab platform.
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in situ bioremediation of naphthenic acids contaminated Tailing Pond waters in the athabasca oil sands region demonstrated field studies and plausible options a review
Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 2005Co-Authors: E K Quagraine, H G Peterson, John V HeadleyAbstract:Currently, there are three industrial plants that recover oil from the lower Athabasca oil sands area, and there are plans in the future for several additional mines. The extraction procedures produce large volumes of slurry wastes contaminated with naphthenic acids (NAs). Because of a "zero discharge" policy the oil sands companies do not release any extraction wastes from their leases. The process-affected waters and fluid Tailings contaminated with NAs are contained on-site primarily in large settling Ponds. These fluid wastes from the Tailing Ponds can be acutely and chronically toxic to aquatic organisms, and NAs have been associated with this toxicity. The huge Tailings containment area must ultimately be reclaimed, and this is of major concern to the oil sands industry. Some reclamation options have been investigated by both pioneering industries (Syncrude Energy Inc. and Suncor Inc.) with mixed results. The bioremediation techniques have limited success to date in biodegrading NAs to levels below 19 mg/L. Some Tailing Pond waters have been stored for more than 10 years, and it appears that the remaining high molecular weight NAs are refractory to the natural biodegradation process in the Ponds. Some plausible options to further degrade the NAs in the Tailings Pond water include: bioaugmentation with bacteria selected to degrade the more refractory classes of NAs; the use of attachment materials such as clays to concentrate both the NA and the NA-degrading bacteria in their surfaces and/or pores; synergistic association between algae and bacteria consortia to promote efficient aerobic degradation; and biostimulation with nutrients to promote the growth and activity of the microorganisms.
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is biodegradation of bitumen a source of recalcitrant naphthenic acid mixtures in oil sands Tailing Pond waters
Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 2005Co-Authors: E K Quagraine, John V Headley, H G PetersonAbstract:Carboxylic acids are transient metabolites during the mineralization of petroleum hydrocarbons. Crude oils, however, vary in their proportion of the hydrocarbon components. Depending on structure, some carboxylic acid metabolites resist further biodegradation and persist in aquatic systems. During the extraction of oil sands bitumen, recalcitrant carboxylic acid mixtures, collectively referred to as naphthenic acids (NAs), are released into the wastewaters. These waters also contain unrecovered bitumen from the oil sands. The unextracted bitumen is often overlooked as a possible source of the petroleum acids. The present article discusses the literature data on the biotransformation of hydrocarbons in bitumen from oil sands to the corresPonding petroleum carboxylic acids. Some insight is given on the mechanism of the biodegradation process. The susceptibility to biodegradation is affected by differences in alicyclic carboxylic acids such as carbon chain length, chain branching, and the oddness or evenness of carbon chain containing the carboxylic group, positions where alkyl groups are substituted on the cyclic ring, geometrical isomerism, and number of cyclic rings.
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in situ bioremediation of naphthenic acids contaminated Tailing Pond waters in the athabasca oil sands region demonstrated field studies and plausible options a review
Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 2005Co-Authors: E K Quagraine, H G Peterson, John V HeadleyAbstract:Abstract Currently, there are three industrial plants that recover oil from the lower Athabasca oil sands area, and there are plans in the future for several additional mines. The extraction procedures produce large volumes of slurry wastes contaminated with naphthenic acids (NAs). Because of a “zero discharge” policy the oil sands companies do not release any extraction wastes from their leases. The process-affected waters and fluid Tailings contaminated with NAs are contained on-site primarily in large settling Ponds. These fluid wastes from the Tailing Ponds can be acutely and chronically toxic to aquatic organisms, and NAs have been associated with this toxicity. The huge Tailings containment area must ultimately be reclaimed, and this is of major concern to the oil sands industry. Some reclamation options have been investigated by both pioneering industries (Syncrude Energy Inc. and Suncor Inc.) with mixed results. The bioremediation techniques have limited success to date in biodegrading NAs to leve...
L Galvezbravo - One of the best experts on this subject based on the ideXlab platform.
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recolonization process and fish assemblage dynamics in the guadiamar river sw spain after the aznalcollar mine toxic spill
River Research and Applications, 2016Co-Authors: R J De Miguel, L Galvezbravo, Francisco J Olivapaterna, Luis Cayuela, C FernandezdelgadoAbstract:The Guadiamar River (SW Iberian Peninsula) received a major toxic spill (6 hm3) from a Tailing Pond in 1998 that defaunated 67 km of the main stem. Following early mud removal works, the fish assemblage was annually monitored at four affected sampling sites and one located in the upstream non-affected reach of the Guadiamar River as reference. Fish abundance and assemblage structure were analysed. Principal response curve was applied to assess the recovery trends and to identify the most influential species. A non-metric multidimensional scaling ordination and permutational multivariate analysis of variance were applied to evaluate changes in fish assemblage structure between sites and years. Overall, the affected reaches harboured fish within 2 years of the spill. Colonists arrived mainly from the upstream and downstream non-affected Guadiamar River reaches and, to a lesser extent, from three lateral tributaries. It is likely that the proximity, connectivity and environmental conditions of non-affected fish sources greatly influenced the recolonization process in each site. The structure of the fish community in the affected sites was initially similar to that in the unaffected reference stretch but changed dramatically with time, and each site followed its own trajectory. Currently, long-term threats such as mining leachates, urban sewage, agricultural pollution and exotic fish species expansion have probably exceeded the initial spill effect. This highlights the large effect of anthropogenic factors on freshwater ecosystem resilience, and the need to significantly reduce both pollution and exotic species if the affected reach of the Guadiamar River is to recover fully. Copyright © 2015 John Wiley & Sons, Ltd.
R J De Miguel - One of the best experts on this subject based on the ideXlab platform.
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recolonization process and fish assemblage dynamics in the guadiamar river sw spain after the aznalcollar mine toxic spill
River Research and Applications, 2016Co-Authors: R J De Miguel, L Galvezbravo, Francisco J Olivapaterna, Luis Cayuela, C FernandezdelgadoAbstract:The Guadiamar River (SW Iberian Peninsula) received a major toxic spill (6 hm3) from a Tailing Pond in 1998 that defaunated 67 km of the main stem. Following early mud removal works, the fish assemblage was annually monitored at four affected sampling sites and one located in the upstream non-affected reach of the Guadiamar River as reference. Fish abundance and assemblage structure were analysed. Principal response curve was applied to assess the recovery trends and to identify the most influential species. A non-metric multidimensional scaling ordination and permutational multivariate analysis of variance were applied to evaluate changes in fish assemblage structure between sites and years. Overall, the affected reaches harboured fish within 2 years of the spill. Colonists arrived mainly from the upstream and downstream non-affected Guadiamar River reaches and, to a lesser extent, from three lateral tributaries. It is likely that the proximity, connectivity and environmental conditions of non-affected fish sources greatly influenced the recolonization process in each site. The structure of the fish community in the affected sites was initially similar to that in the unaffected reference stretch but changed dramatically with time, and each site followed its own trajectory. Currently, long-term threats such as mining leachates, urban sewage, agricultural pollution and exotic fish species expansion have probably exceeded the initial spill effect. This highlights the large effect of anthropogenic factors on freshwater ecosystem resilience, and the need to significantly reduce both pollution and exotic species if the affected reach of the Guadiamar River is to recover fully. Copyright © 2015 John Wiley & Sons, Ltd.
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Recolonization process and fish assemblage dynamics in the Guadiamar river (SW Spain) after the Aznalcóllar mine toxic spill
'Wiley', 2016Co-Authors: R J De Miguel, Gálvez Bravo Lucía, Oliva-paterna F. J., Cayuela Luis, Fernández-delgado C.Abstract:The Guadiamar River (SW Iberian Peninsula) received a major toxic spill (6 hm) from a Tailing Pond in 1998 that defaunated 67 km of the main stem. Following early mud removal works, the fish assemblage was annually monitored at four affected sampling sites and one located in the upstream non-affected reach of the Guadiamar River as reference. Fish abundance and assemblage structure were analysed. Principal response curve was applied to assess the recovery trends and to identify the most influential species. A non-metric multidimensional scaling ordination and permutational multivariate analysis of variance were applied to evaluate changes in fish assemblage structure between sites and years. Overall, the affected reaches harboured fish within 2 years of the spill. Colonists arrived mainly from the upstream and downstream non-affected Guadiamar River reaches and, to a lesser extent, from three lateral tributaries. It is likely that the proximity, connectivity and environmental conditions of non-affected fish sources greatly influenced the recolonization process in each site. The structure of the fish community in the affected sites was initially similar to that in the unaffected reference stretch but changed dramatically with time, and each site followed its own trajectory. Currently, long-term threats such as mining leachates, urban sewage, agricultural pollution and exotic fish species expansion have probably exceeded the initial spill effect. This highlights the large effect of anthropogenic factors on freshwater ecosystem resilience, and the need to significantly reduce both pollution and exotic species if the affected reach of the Guadiamar River is to recover fully.This studywas supported by the Guadiama rGreen Corridor Research Program (PICOVER) and the Green Corridor Ecorregional Monitoring Plan (SECOVER) provided by the Andalusian Regional Government. L. Gálvez-Bravo was supported by a postdoctoral fellowship from the Junta de Comunidades de Castilla La-Mancha and the European Social Fund.Peer Reviewe
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Fish composition in the Guadiamar River basin after one of the worst mining spills in Europe
2015Co-Authors: R J De Miguel, F. J. Oliva-paterna, L. Gálvez-bravo, C. Fernández-delgadoAbstract:Fish composition in the Guadiamar River basin after one of the worst mining spills in Europe On 25 April 1998, the Tailing Pond of the Los Frailes mine in Aznalcollar (Seville, Spain) ruptured, causing one of the most harmful environmental disasters in Europe in recent decades. Through the crack, 6 hm3 of acidic water and metallic mud were spilt, defaunating a large area of the Guadiamar River. After the spill cleanup and habitat restoration, multiple anthropogenic impacts continued to degrade the affected area. This work aimed to provide the most updated list of fish species in the Guadiamar River basin after the spill. Data were collected between 1999 and 2011 by electrofishing, light-traps, minnow-traps and multimesh gill-nests in 78 sampling sites. Species richness values for both native and exotic species in the Guadiamar River basin were high when compared with values for other right bank tributaries of the Guadalquivir River. This may be due to direct contact with the mouth of the Guadalquivir, which allowed the presence of migratory species. It may also be due to its location in the lower part of the Guadalquivir River basin, where exotic species accumulated. Among the Guadiamar River basin species, Luciobarbus sclateri and Squalius alburnoides have the widest distribution. The former is a generalist species resistant to unfavourable habitat changes, and the latter has a very successful breeding strategy. However, when focused on the affected area, there was a marked increase in exotic species, and both pumpkinseed (Lepomis gibbosus) and carp (Cyprinus carpio) co-dominated together with the native L. sclateri and S. alburnoides. The distribution of specie
