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Robert M. Kalin - One of the best experts on this subject based on the ideXlab platform.
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The development and use of Permeable Reactive Barrier technologies and potential future applications in the UK
IAHS-AISH publication, 2020Co-Authors: Brian Bone, R. C. Harris, J. W. N. Smith, G. Boshoff, Robert M. Kalin, R Thurgood, Philip MorganAbstract:This chapter looks at the development and use of Permeable Reactive Barrier technologies and potential future applications in the UK
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performance of a field scale biological Permeable Reactive Barrier for in situ remediation of nitrate contaminated groundwater
Science of The Total Environment, 2019Co-Authors: Oriol Gibert, Trevor Elliot, A Assal, Hayley Devlin, Robert M. KalinAbstract:We report the performance of a field-scale Permeable Reactive Barrier (PRB) for the biological treatment of nitrate-contaminated groundwater. The Reactive material of the PRB consisted of a mixture of gravel and mulch as a carbon source for denitrifying bacteria. The PRB was equipped with a delivery system that allowed injecting NO3- at controlled rates from the surface directly into the up-gradient layer of the PRB. This way, NO3- concentration entering the PRB was varied (from 1 to 530 mg/L) with the purpose of evaluating the ultimate efficiency of the PRB under different NO3- loadings. The PRB was successful at removing NO3- from groundwater at inlet concentrations up to 280 mg/L (with NO3- removal percentages ≥97%). Monitoring of groundwater at different depths within the PRB provided evidence that NO3- underwent denitrification preferably at the deepest part of the PRB, where more favourable reducing conditions were achieved. Among the shortcomings of the PRB were the fluctuations of groundwater fluxes caused by intense rainfalls during the study period, although they generally did not pose concern for the denitrification capacity of the PRB. Emission fluxes of gases (CO2, CH4 and N2O) from the PRB to the atmosphere were also measured. The results are finally compared with the few others reported existing PRBs for nitrate-contaminated groundwater worldwide.
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ten year performance evaluation of a field scale zero valent iron Permeable Reactive Barrier installed to remediate trichloroethene contaminated groundwater
Environmental Science & Technology, 2010Co-Authors: Debra Phillips, Leen Bastiaens, T Van Nooten, M I Russell, Keith Dickson, S Plant, J M E Ahad, T Newton, Trevor Elliot, Robert M. KalinAbstract:The Monkstown zero-valent iron Permeable Reactive Barrier (ZVI PRB), Europe’s oldest commercially-installed ZVI PRB, had been treating trichloroethene (TCE) contaminated groundwater for about 10 years on the Nortel Network site in Northern Ireland when cores from the Reactive zone were collected in December, 2006. Groundwater data from 2001−2006 indicated that TCE is still being remediated to below detection limits as the contaminated groundwater flows through the PRB. Ca and Fe carbonates, crystalline and amorphous Fe sulfides, and Fe (hydr)oxides have precipitated in the granular ZVI material in the PRB. The greatest variety of minerals is associated with a ∼1-2 cm thick, slightly cemented crust on top (up-gradient influent entrance) of the ZVI section of the PRB and also with the discontinuous cemented ZVI material (∼23 cm thick) directly below it. The greatest presence of microbial communities also occurred in the up-gradient influent portion of the PRB compared to its down-gradient effluent section, ...
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selection of organic substrates as potential Reactive materials for use in a denitrification Permeable Reactive Barrier prb
Bioresource Technology, 2008Co-Authors: Oriol Gibert, Sylwia Pomierny, Ivan Rowe, Robert M. KalinAbstract:The aim of the present study was to select a suitable natural organic substrate as a potential carbon source for use in a denitrification Permeable Reactive Barrier (PRB). A number of seven organic substrates were first tested in batch tests. The materials attained varying degrees of success at promoting denitrification. Some of the organic substrates performed very well, achieving complete nitrate removal (>98%), while others were considered unsuitable for a variety of reasons, including: insufficient nitrate or nitrogen removal, excessive release of leachable nitrogen from the substrate or excessive reduction of nitrate to ammonium rather than removing it as gaseous N2. The top performing substrate in terms of denitrification extent (>98%) and rate () was then selected for two bench-scale column experiments in an attempt to simulate the PRB. The inlet concentration was 50 mg dm−3 and the columns operated at two different flow rates: 0.3 cm3 min−1 (Column 1) and 1.1 cm3 min−1 (Column 2). The two columns showed different general patterns, making it clear that the flow rate was a key factor at the nitrate removal. Nitrate was completely removed (>96%) by the passage through Column 1, while only partially removed in Column 2 (66%). The results indicated that the selected organic substrate (Softwood) was applicable for further use as a filling material for a PRB.
David W Blowes - One of the best experts on this subject based on the ideXlab platform.
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geochemical and isotope study of trichloroethene degradation in a zero valent iron Permeable Reactive Barrier a twenty two year performance evaluation
Environmental Science & Technology, 2019Co-Authors: Richard T Wilkin, David W Blowes, Steven D Acree, Robert W Puls, Molly R Sexton, Christopher Kalinowski, Jennifer M Tilton, Leilani L WoodsAbstract:This study provides a twenty-two-year record of in situ degradation of chlorinated organic compounds by a granular iron Permeable Reactive Barrier (PRB). Groundwater concentrations of trichloroethene (TCE) entering the PRB were as high as 10670 μg/L. Treatment efficiency ranged from 81 to >99%, and TCE concentrations from C4 compounds, and possibly CO2(aq) and methane. Abiotic patterns of TCE degradation were indicated by compound-specific stable isotope data and the distribution of degradation products. δ13C values of methane within and down-gradient of the PRB varied widely from −94‰ to −16‰; these values cover most of the isotopic range encountered in natural methanog...
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Longevity Estimates for a Permeable Reactive Barrier System Remediating a 90Sr Plume
Uranium - Past and Future Challenges, 2014Co-Authors: Jutta Hoppe, Sung-wook Jeen, David W BlowesAbstract:A Permeable Reactive Barrier system, known as the Wall and Curtain, was installed at the Chalk River Laboratories, Chalk River, Ontario, in 1998, to intercept a 90Sr plume. The system employs clinoptilolite, a zeolite, as a Reactive material which adsorbs 90Sr. Reactive transport simulations of the site were conducted using the numerical code HydroGeoSphere to provide longevity estimates for the system. The HydroGeoSphere simulations included three solutes, for which zoned distribution coefficients were specified. Longevity estimates derived from the simulation were between 70 and 100 years for the Wall and Curtain system.
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process based Reactive transport modeling of a Permeable Reactive Barrier for the treatment of mine drainage
Journal of Contaminant Hydrology, 2006Co-Authors: K U Mayer, Shawn G Benner, David W BlowesAbstract:Abstract Reactive transport modeling of a Permeable Reactive Barrier for the treatment of mine drainage was used to integrate a comprehensive data set including pore water chemistry and solid phase data from several sampling events over a >3-year time period. The simulations consider the reduction of sulfate by the organic carbon-based treatment material and the removal of sulfate and iron by precipitation of reduced mineral phases including iron monosulfides and siderite. Additional parameters constraining the model include dissolved H 2 S, alkalinity and pH, as well as a suite of solid phase S-fractions identified by extractions. Influences of spatial heterogeneity necessitated the use of a 2-dimensional modeling approach. Simulating observed seasonal fluctuations and long-term changes in Barrier reactivity required the use of temperature dependent rate coefficients and a multimodal Monod-type rate expression accounting for the variable reactivity of different organic carbon fractions. Simulated dissolved concentrations of SO 4 , Fe, H 2 S, alkalinity and pH, as well as solid phase accumulations of reduced sulfur phases generally compare well to observed trends over 23 months. Spatial variations, seasonal fluctuations and the time-dependent decline in reactivity were also captured. The modeling results generally confirm, and further strengthen, the existing conceptual model for the site. Overall sulfate reduction and S-accumulation rates are constrained with confidence within a factor of 1.5.
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a Permeable Reactive Barrier for treatment of heavy metals
Ground Water, 2002Co-Authors: Ralph D Ludwig, Rick Mcgregor, David W Blowes, Shawn G Benner, Keith MountjoyAbstract:: Historical storage of ore concentrate containing sulfide minerals at an industrial site in British Columbia, Canada, has resulted in widespread contamination of the underlying soil and ground water. The oxidation of sulfide minerals has released significant quantities of heavy metals, including Cu, Cd, Co, Ni, and Zn, into the ground water. A pilot-scale, compost-based, sulfate-reducing Permeable Reactive Barrier was installed in the path of the dissolved heavy-metal plume. The Permeable Reactive Barrier uses sulfate-reducing bacteria to promote precipitation of heavy metals as insoluble metal sulfides. Monitoring over a 21-month period indicated significant removal of heavy metals within the Barrier. Copper concentrations declined from a mean concentration of 3,630 pg/L in the influent to a mean concentration within the Barrier of 10.5 microg/L, Cd from 15.3 microg/L to 0.2 microg/L, Co from 5.3 microg/L to 1.1 microg/L, Ni from 131 pg/L to 33.0 microg/L, and Zn from 2,410 microg/L to 136 pg/L. Within the lower half of the Barrier where tidal influences were more limited and sulfate-reducing conditions were better maintained, mean treatment levels of 2.9 microg/L (Cu), 0.1 microg/L (Cd), 0.4 microg/L (Co), 2.7 microg/L (Ni), and 6.3 microg/L (Zn) were observed.
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geochemistry of a Permeable Reactive Barrier for metals and acid mine drainage
Environmental Science & Technology, 1999Co-Authors: Shawn G Benner, David W Blowes, W D Gould, Roger B Herbert, Carol J PtacekAbstract:A Permeable Reactive Barrier, designed to remove metals and generate alkalinity by promoting sulfate reduction and metal sulfide precipitation, was installed in August 1995 into an aquifer containing effluent from mine tailings. Passage of groundwater through the Barrier results in striking improvement in water quality. Dramatic changes in concentrations of SO4 (decrease of 2000−3000 mg/L), Fe (decrease of 270−1300 mg/L), trace metals (e.g., Ni decreases 30 mg/L), and alkalinity (increase of 800−2700 mg/L) are observed. Populations of sulfate reducing bacteria are 10 000 times greater, and bacterial activity, as measured by dehydrogenase activity, is 10 times higher within the Barrier compared to the up-gradient aquifer. Dissolved sulfide concentrations increase by 0.2−120 mg/L, and the isotope 34S is enriched relative to 32S in the dissolved phase SO42- within the Barrier. Water chemistry, coupled with geochemical speciation modeling, indicates the pore water in the Barrier becomes supersaturated with re...
Leilani L Woods - One of the best experts on this subject based on the ideXlab platform.
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geochemical and isotope study of trichloroethene degradation in a zero valent iron Permeable Reactive Barrier a twenty two year performance evaluation
Environmental Science & Technology, 2019Co-Authors: Richard T Wilkin, David W Blowes, Steven D Acree, Robert W Puls, Molly R Sexton, Christopher Kalinowski, Jennifer M Tilton, Leilani L WoodsAbstract:This study provides a twenty-two-year record of in situ degradation of chlorinated organic compounds by a granular iron Permeable Reactive Barrier (PRB). Groundwater concentrations of trichloroethene (TCE) entering the PRB were as high as 10670 μg/L. Treatment efficiency ranged from 81 to >99%, and TCE concentrations from C4 compounds, and possibly CO2(aq) and methane. Abiotic patterns of TCE degradation were indicated by compound-specific stable isotope data and the distribution of degradation products. δ13C values of methane within and down-gradient of the PRB varied widely from −94‰ to −16‰; these values cover most of the isotopic range encountered in natural methanog...
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fifteen year assessment of a Permeable Reactive Barrier for treatment of chromate and trichloroethylene in groundwater
Science of The Total Environment, 2014Co-Authors: Richard T Wilkin, Steven D Acree, Randall R Ross, Robert W Puls, Leilani L WoodsAbstract:Abstract The fifteen-year performance of a granular iron, Permeable Reactive Barrier (PRB; Elizabeth City, North Carolina) is reviewed with respect to contaminant treatment (hexavalent chromium and trichloroethylene) and hydraulic performance. Due to in-situ treatment of the chromium source zone, Reactive and hydraulic longevity of the PRB has outlived the mobile chromate plume. Chromium concentrations exceeding 3 μg/L have not been detected in regions located hydraulically down-gradient of the PRB. Trichloroethylene treatment has also been effective, although non-constant influent concentrations of trichloroethylene have at times resulted in incomplete dechlorination. Daughter products: cis-1,2-dichloroethylene, vinyl chloride, ethene, and ethane have been observed within and down-gradient of the PRB at levels
Oriol Gibert - One of the best experts on this subject based on the ideXlab platform.
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performance of a field scale biological Permeable Reactive Barrier for in situ remediation of nitrate contaminated groundwater
Science of The Total Environment, 2019Co-Authors: Oriol Gibert, Trevor Elliot, A Assal, Hayley Devlin, Robert M. KalinAbstract:We report the performance of a field-scale Permeable Reactive Barrier (PRB) for the biological treatment of nitrate-contaminated groundwater. The Reactive material of the PRB consisted of a mixture of gravel and mulch as a carbon source for denitrifying bacteria. The PRB was equipped with a delivery system that allowed injecting NO3- at controlled rates from the surface directly into the up-gradient layer of the PRB. This way, NO3- concentration entering the PRB was varied (from 1 to 530 mg/L) with the purpose of evaluating the ultimate efficiency of the PRB under different NO3- loadings. The PRB was successful at removing NO3- from groundwater at inlet concentrations up to 280 mg/L (with NO3- removal percentages ≥97%). Monitoring of groundwater at different depths within the PRB provided evidence that NO3- underwent denitrification preferably at the deepest part of the PRB, where more favourable reducing conditions were achieved. Among the shortcomings of the PRB were the fluctuations of groundwater fluxes caused by intense rainfalls during the study period, although they generally did not pose concern for the denitrification capacity of the PRB. Emission fluxes of gases (CO2, CH4 and N2O) from the PRB to the atmosphere were also measured. The results are finally compared with the few others reported existing PRBs for nitrate-contaminated groundwater worldwide.
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performance of a field scale Permeable Reactive Barrier based on organic substrate and zero valent iron for in situ remediation of acid mine drainage
Environmental Science and Pollution Research, 2013Co-Authors: Oriol Gibert, J L Cortina, Joan De Pablo, Carlos AyoraAbstract:A Permeable Reactive Barrier (PRB) was installed in Aznalcollar (Spain) in order to rehabilitate the Agrio aquifer groundwater severely contaminated with acid mine drainage after a serious mining accident. The filling material of the PRB consisted of a mixture of calcite, vegetal compost and, locally, Fe0 and sewage sludge. Among the successes of the PRB are the continuous neutralisation of pH and the removal of metals from groundwater within the PRB (removals of >95 %). Among the shortcomings are the improper PRB design due to the complexity of the internal structure of the Agrio alluvial deposits (which resulted in an inefficient capture of the contaminated plume), the poor degradability of the compost used and the short residence time within the PRB (which hindered a complete sulphate reduction), the clogging of a section of the PRB and the heterogeneities of the filling material (which resulted in preferential flows within the PRB). Undoubtedly, it is only through accumulated experience at field-scale systems that the potentials and limits of the PRB technology can be determined.
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in situ remediation of acid mine drainage using a Permeable Reactive Barrier in aznalcollar sw spain
Journal of Hazardous Materials, 2011Co-Authors: Oriol Gibert, Tobias S Rotting, J L Cortina, Joan De Pablo, Carlos Ayora, Jesus Carrera, J BolziccoAbstract:Abstract Following on the accident occurred in Aznalcollar in 1998, whereby a huge amount of acid mine drainage and heavy metal-bearing pyritic sludge was released to the Agrio river valley with the subsequent contamination of groundwater, a subsurface Permeable Reactive Barrier (PRB) was installed to mitigate the long-term impacts by the spillage. The PRB material consisted of a mixture of limestone and vegetal compost. A particular characteristic of the Agrio aquifer is its high water flow velocity (0.5–1 m/d), which may pose difficulties in its remediation using PRB technology. The present study reports the 36-month performance of the PRB. Vertical differences in water velocity were observed within the PRB, with the deeper part being slower and more effective in neutralizing pH and removing heavy metals (Zn, Al, Cu). On the other hand, partial sulfate removal appeard to be restricted to the bottom of the PRB, but with no apparent influence on downgradient water quality. The results are finally compared with the other four reported existing PRBs for AMD worldwide.
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selection of organic substrates as potential Reactive materials for use in a denitrification Permeable Reactive Barrier prb
Bioresource Technology, 2008Co-Authors: Oriol Gibert, Sylwia Pomierny, Ivan Rowe, Robert M. KalinAbstract:The aim of the present study was to select a suitable natural organic substrate as a potential carbon source for use in a denitrification Permeable Reactive Barrier (PRB). A number of seven organic substrates were first tested in batch tests. The materials attained varying degrees of success at promoting denitrification. Some of the organic substrates performed very well, achieving complete nitrate removal (>98%), while others were considered unsuitable for a variety of reasons, including: insufficient nitrate or nitrogen removal, excessive release of leachable nitrogen from the substrate or excessive reduction of nitrate to ammonium rather than removing it as gaseous N2. The top performing substrate in terms of denitrification extent (>98%) and rate () was then selected for two bench-scale column experiments in an attempt to simulate the PRB. The inlet concentration was 50 mg dm−3 and the columns operated at two different flow rates: 0.3 cm3 min−1 (Column 1) and 1.1 cm3 min−1 (Column 2). The two columns showed different general patterns, making it clear that the flow rate was a key factor at the nitrate removal. Nitrate was completely removed (>96%) by the passage through Column 1, while only partially removed in Column 2 (66%). The results indicated that the selected organic substrate (Softwood) was applicable for further use as a filling material for a PRB.
Ming-hsu Li - One of the best experts on this subject based on the ideXlab platform.
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Assessing the performance of a Permeable Reactive Barrier–aquifer system using a dual-domain solute transport model
Journal of Hydrology, 2016Co-Authors: Jui-sheng Chen, Ming-hsu LiAbstract:Abstract Transport behavior through a Permeable Reactive Barrier (PRB)-aquifer system is complicated because of the different physical and chemical properties of the PRB and the aquifer. Dual-domain solute transport models are efficient tools for better understanding the various processes and mechanisms of Reactive solute transport through a PRB–aquifer system. This study develops a dual-domain analytical model to assess the physical and chemical processes of two-dimensional Reactive solute transport through a PRB–aquifer system. The dispersion processes of a dual–domain system on the solute transport are investigated. The results show that the dispersion parameters in a dual-domain system synchronously govern the dynamic shape of the contaminant plume. The low longitudinal and transverse dispersion coefficients of a dual-domain system may restrict the spreading of the plume and elevate the plume’s concentration level. The derived analytical solution is applied to explore how the different Reactive transport processes affect the performance of a PRB-aquifer system. The results show that the first-order decay rate constant of the PRB has a critical effect on the performance of the PRB-aquifer system, whereas the effects of the physical dispersion properties on PRB performance are less significant.
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assessing the performance of a Permeable Reactive Barrier aquifer system using a dual domain solute transport model
Journal of Hydrology, 2016Co-Authors: Jui-sheng Chen, Ming-hsu LiAbstract:Abstract Transport behavior through a Permeable Reactive Barrier (PRB)-aquifer system is complicated because of the different physical and chemical properties of the PRB and the aquifer. Dual-domain solute transport models are efficient tools for better understanding the various processes and mechanisms of Reactive solute transport through a PRB–aquifer system. This study develops a dual-domain analytical model to assess the physical and chemical processes of two-dimensional Reactive solute transport through a PRB–aquifer system. The dispersion processes of a dual–domain system on the solute transport are investigated. The results show that the dispersion parameters in a dual-domain system synchronously govern the dynamic shape of the contaminant plume. The low longitudinal and transverse dispersion coefficients of a dual-domain system may restrict the spreading of the plume and elevate the plume’s concentration level. The derived analytical solution is applied to explore how the different Reactive transport processes affect the performance of a PRB-aquifer system. The results show that the first-order decay rate constant of the PRB has a critical effect on the performance of the PRB-aquifer system, whereas the effects of the physical dispersion properties on PRB performance are less significant.