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Jiang Y, Lu R, Chen Y, Deng R, Deng X. Effect of Fe 2+-activated persulfate combined with biodegradation in removing gasoline BTX from karst groundwater: A box-column experimental study. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024:10.1007/s11356-024-34597-9. [PMID: 39102137 DOI: 10.1007/s11356-024-34597-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 07/29/2024] [Indexed: 08/06/2024]
Abstract
In-situ chemical oxidation with persulfate (PS-ISCO) is a preferred approach for the remediation of fuel-contaminated groundwater. Persulfate (PS) can be activated by various methods to produce stronger sulfate radicals for more efficient ISCO. Despite karst aquifers being widespread, there are few reports on PS-ISCO combined with Fe2+-activated PS. To better understand the effects of Fe2+-activated PS for the remediation of gasoline-contaminated aquifers in karst areas, a box-column experiment was conducted under flow conditions, using karst groundwater and limestone particles to simulate an aquifer. Gasoline was used as the source of hydrocarbon contaminants. Dissolved oxygen and nitrate were added to enhance bioremediation (EBR) and ferrous sulfate was used to activate PS. The effect of Fe2+-activated PS combined with biodegradation was compared during the periods of EBR + ISCO and ISCO alone, using the mass flow method for data analysis. The results showed that the initial dissolution of benzene, toluene, and xylene (BTX) from gasoline injection was rapid and variable, with a decaying trend at an average pseudo-first-order degradation rate constant of 0.032 d-1. Enhanced aerobic biodegradation and denitrification played a significant role in limestone-filled environments, with dissolved oxygen and nitrate utilization ratios of 59 ~ 72% and 12-70%, respectively. The efficiency of EBR + ISCO was the best method for BTX removal, compared with EBR or ISCO alone. The pseudo-first-order degradation rate constants of BTX reached 0.022-0.039, 0.034-0.070, and 0.027-0.036 d-1, during the periods of EBR alone, EBR + ISCO, and ISCO alone, respectively. The EBR + ISCO had a higher BTX removal ratio range of 71.0 ~ 84.3% than the ISCO alone with 30.1 ~ 45.1%. The presence of Fe2+-activated PS could increase the degradation rate of BTX with a range of 0.060 ~ 0.070 d-1, otherwise, with a range of 0.034-0.052 d-1. However, Fe2+-activated PS also consumed about 3 times the mass of PS, caused a further decrease in pH with a range of 6.8-7.6, increased 3-4 times the Ca2+ and 1.6-1.8 times the HCO3- levels, and decreased the BTX removal ratio of ISCO + EBR, compared to the case without Fe2+ activation. In addition, the accumulation of ferric hydroxides within a short distance indicated that the range of PS activated by Fe2+ may be limited. Based on this study, it is suggested that the effect of Fe2+-activated PS should be evaluated in the remediation of non-carbonate rock aquifers.
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Affiliation(s)
- Yaping Jiang
- Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin, 541004, China
| | - Renqian Lu
- Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin, 541004, China
| | - Yudao Chen
- Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin, 541004, China.
| | - Ritian Deng
- Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin, 541004, China
| | - Xu Deng
- Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin, 541004, China
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Ciampi P, Esposito C, Bartsch E, Alesi EJ, Petrangeli Papini M. Pump-and-treat (P&T) vs groundwater circulation wells (GCW): Which approach delivers more sustainable and effective groundwater remediation? ENVIRONMENTAL RESEARCH 2023; 234:116538. [PMID: 37399987 DOI: 10.1016/j.envres.2023.116538] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 05/15/2023] [Accepted: 06/30/2023] [Indexed: 07/05/2023]
Abstract
Pump-and-treat (P&T) is commonly used to remediate contaminated groundwater sites. The scientific community is currently engaged in a debate regarding the long-term effectiveness and sustainability of P&T for groundwater remediation. This work aims to provide a quantitative comparative analysis of the performance of an alternative system to traditional P&T, to support the development of sustainable groundwater remediation plans. Two industrial sites with unique geological frameworks and contamination with dense non-aqueous phase liquid (DNAPL) and arsenic (As) respectively, were selected for the study. At both locations, attempts were made for decades to clean up groundwater contamination by pump-and-treat. In response to persistently high levels of pollutants, groundwater circulation wells (GCWs) were installed to explore the possibility of accelerating the remediation process in unconsolidated and rock deposits. This comparative evaluation focuses on the different mobilization patterns observed, resulting variations in contaminant concentration, mass discharge, and volume of extracted groundwater. To facilitate the fusion of multi-source data, including geological, hydrological, hydraulic, and chemical information, and enable the continuous extraction of time-sensitive information, a geodatabase-supported conceptual site model (CSM) is utilized as a dynamic and interactive interface. This approach is used to assess the performance of GCW and P&T at the investigated sites. At Site 1, the GCW stimulated microbiological reductive dichlorination and mobilized significantly higher 1,2-DCE concentrations than P&T, despite recirculating a smaller volume of groundwater. At Site 2, As removal rate by GCW resulted generally higher than pumping wells. One conventional well mobilized higher masses of As in the early stages of P&T. This reflected the P&T's impact on accessible contaminant pools in early operational periods. P&T withdrew a significantly larger volume of groundwater than the GCW. The outcomes unveil the diverse contaminant removal behavior characterizing two distinct remediation strategies in different geological environments, revealing the dynamics and decontamination mechanisms that feature GCWs and P&T and emphasizing the limitations of traditional groundwater extraction systems in targeting aged pollution sources. GCWs have been shown to reduce remediation time, increase mass removal, and minimize the significant water consumption associated with P&T. These benefits pave the way for more sustainable groundwater remediation approaches in various hydrogeochemical scenarios.
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Affiliation(s)
- Paolo Ciampi
- Department of Earth Sciences, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - Carlo Esposito
- Department of Earth Sciences, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - Ernst Bartsch
- IEG Technologie GmbH, Hohlbachweg 2, D-73344, Gruibingen, Baden-Württemberg, Germany.
| | - Eduard J Alesi
- IEG Technologie GmbH, Hohlbachweg 2, D-73344, Gruibingen, Baden-Württemberg, Germany.
| | - Marco Petrangeli Papini
- Department of Chemistry, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
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A Review on Biotechnological Approaches Applied for Marine Hydrocarbon Spills Remediation. Microorganisms 2022; 10:microorganisms10071289. [PMID: 35889007 PMCID: PMC9324126 DOI: 10.3390/microorganisms10071289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/18/2022] [Accepted: 06/21/2022] [Indexed: 12/04/2022] Open
Abstract
The increasing demand for petroleum products generates needs for innovative and reliable methods for cleaning up crude oil spills. Annually, several oil spills occur around the world, which brings numerous ecological and environmental disasters on the surface of deep seawaters like oceans. Biological and physico-chemical remediation technologies can be efficient in terms of spill cleanup and microorganisms—mainly bacteria—are the main ones responsible for petroleum hydrocarbons (PHCs) degradation such as crude oil. Currently, biodegradation is considered as one of the most sustainable and efficient techniques for the removal of PHCs. However, environmental factors associated with the functioning and performance of microorganisms involved in hydrocarbon-degradation have remained relatively unclear. This has limited our understanding on how to select and inoculate microorganisms within technologies of cleaning and to optimize physico-chemical remediation and degradation methods. This review article presents the latest discoveries in bioremediation techniques such as biostimulation, bioaugmentation, and biosurfactants as well as immobilization strategies for increasing the efficiency. Besides, environmental affecting factors and microbial strains engaged in bioremediation and biodegradation of PHCs in marines are discussed.
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Huang X, Shen S, Lin Y. Biodegradation of catechol by
Pseudomonas fluorescens
isolated from petroleum‐impacted soil. CAN J CHEM ENG 2021. [DOI: 10.1002/cjce.23859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Xiaoyan Huang
- Department of Chemical and Biological Engineering University of Saskatchewan Saskatoon Saskatchewan Canada
| | - Siyang Shen
- Department of Chemical and Biological Engineering University of Saskatchewan Saskatoon Saskatchewan Canada
| | - Yen‐Han Lin
- Department of Chemical and Biological Engineering University of Saskatchewan Saskatoon Saskatchewan Canada
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Zhu B, Friedrich S, Wang Z, Táncsics A, Lueders T. Availability of Nitrite and Nitrate as Electron Acceptors Modulates Anaerobic Toluene-Degrading Communities in Aquifer Sediments. Front Microbiol 2020; 11:1867. [PMID: 32922372 PMCID: PMC7456981 DOI: 10.3389/fmicb.2020.01867] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/16/2020] [Indexed: 01/04/2023] Open
Abstract
Microorganisms are essential in the degradation of environmental pollutants. Aromatic hydrocarbons, e.g., benzene, toluene, ethylbenzene, and xylene (BTEX), are common aquifer contaminants, whose degradation in situ is often limited by the availability of electron acceptors. It is clear that different electron acceptors such as nitrate, iron, or sulfate support the activity of distinct degraders. However, this has not been demonstrated for the availability of nitrate vs. nitrite, both of which can be respired in reductive nitrogen cycling. Here via DNA-stable isotope probing, we report that nitrate and nitrite provided as electron acceptors in different concentrations and ratios not only modulated the microbial communities responsible for toluene degradation but also influenced how nitrate reduction proceeded. Zoogloeaceae members, mainly Azoarcus spp., were the key toluene degraders with nitrate-only, or both nitrate and nitrite as electron acceptors. In addition, a shift within Azoarcus degrader populations was observed on the amplicon sequence variant (ASV) level depending on electron acceptor ratios. In contrast, members of the Sphingomonadales were likely the most active toluene degraders when only nitrite was provided. Nitrate reduction did not proceed beyond nitrite in the nitrate-only treatment, while it continued when nitrite was initially also present in the microcosms. Likely, this was attributed to the fact that different microbial communities were stimulated and active in different microcosms. Together, these findings demonstrate that the availability of nitrate and nitrite can define degrader community selection and N-reduction outcomes. It also implies that nitrate usage efficiency in bioremediation could possibly be enhanced by an initial co-supply of nitrite, via modulating the active degrader communities.
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Affiliation(s)
- Baoli Zhu
- Chair of Ecological Microbiology, University of Bayreuth, Bayreuth, Germany
| | | | - Zhe Wang
- Chair of Ecological Microbiology, University of Bayreuth, Bayreuth, Germany
| | - András Táncsics
- Regional University Center of Excellence in Environmental Industry, Szent Istvan University, Gödöllö, Hungary
| | - Tillmann Lueders
- Chair of Ecological Microbiology, University of Bayreuth, Bayreuth, Germany
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Oliveira V, Gomes NCM, Santos M, Almeida A, Lillebø AI, Ezequiel J, Serôdio J, Silva AMS, Simões MMQ, Rocha SM, Cunha Â. Effects of the Inoculant Strain Pseudomonas sp. SPN31 nah + and of 2-Methylnaphthalene Contamination on the Rhizosphere and Endosphere Bacterial Communities of Halimione portulacoides. Curr Microbiol 2017; 74:575-583. [DOI: 10.1007/s00284-017-1197-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 01/08/2017] [Indexed: 01/19/2023]
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Li Y, Chen L, Liu Y, Liu F, Fallgren PH, Jin S. Effects of bioaugmentation on sorption and desorption of benzene, 1,3,5-trimethylbenzene and naphthalene in freshly-spiked and historically-contaminated sediments. CHEMOSPHERE 2016; 162:1-7. [PMID: 27474910 DOI: 10.1016/j.chemosphere.2016.07.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 07/13/2016] [Accepted: 07/15/2016] [Indexed: 06/06/2023]
Abstract
This work investigated the frequently observed "rebounds" of contaminants of concern in groundwater systems. Specifically, influences of bioaugmented microorganisms on the sorption and desorption of representative petroleum constituents [benzene, 1,3,5-trimethylbenzene and naphthalene (BTN)] were studied in freshly-spiked and historically-contaminated sediments. Capable microorganisms were enriched and supplemented to contaminated sediments to enhance biodegradation of petroleum hydrocarbons. In freshly-spiked sediments, when petroleum-degrading microorganisms were added, concentrations of dissolved petroleum constituents appeared to increase initially, and 12.4, 14.0 and 20.0 mg/kg of benzene, 1,3,5-trimethylbenzene and naphthalene, respectively desorbed from the sediments into the water phase. In the historically-contaminated sediments, the augmentation of petroleum-degrading microorganisms led to the desorption of 0.023-0.059, 0009-0.016, and 1.731-2.763 mg/L of previously sequestrated BTN into the water phase, and also triggered the desorption of 0.051-0.223, -0.133-2.630, and 2.324-1.200 mg/kg of previously sequestrated BTN as the methanol extraction quantity. The mechanisms of the enhanced desorption at the presence of microbes remain to be determined; however, we presumed that microbially produced constituents such as biosurfactants and cell mass could have attributed to the partition of petroleum compounds from the sediments. Findings from this study may partially explain "rebounds" of certain petroleum constituents into the groundwater during in situ bioremediation practice, although such immediate rebounds sometimes are weak, and the desorbed constituents can be eventually biodegraded under proper biogeochemical conditions.
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Affiliation(s)
- YueHua Li
- State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, PR China; School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, PR China
| | - Liang Chen
- State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, PR China; School of Civil Engineering, Tianjin University, Tianjin 300072, PR China.
| | - YuLong Liu
- Research Institute of Safety and Environment Technology, China National Petroleum Corporation, Beijing 102206, PR China
| | - Fei Liu
- Beijing Key Laboratory of Water Resources and Environmental Engineering, China University of Geosciences, Beijing 100083, PR China
| | - Paul H Fallgren
- Advanced Environmental Technologies, LLC, Fort Collins, CO 80525, USA
| | - Song Jin
- Advanced Environmental Technologies, LLC, Fort Collins, CO 80525, USA
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Wells NS, Hakoun V, Brouyère S, Knöller K. Multi-species measurements of nitrogen isotopic composition reveal the spatial constraints and biological drivers of ammonium attenuation across a highly contaminated groundwater system. WATER RESEARCH 2016; 98:363-375. [PMID: 27124126 DOI: 10.1016/j.watres.2016.04.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/28/2016] [Accepted: 04/13/2016] [Indexed: 06/05/2023]
Abstract
Groundwater under industrial sites is characterised by heterogeneous chemical mixtures, making it difficult to assess the fate and transport of individual contaminants. Quantifying the in-situ biological removal (attenuation) of nitrogen (N) is particularly difficult due to its reactivity and ubiquity. Here a multi-isotope approach is developed to distinguish N sources and sinks within groundwater affected by complex industrial pollution. Samples were collected from 70 wells across the two aquifers underlying a historic industrial area in Belgium. Below the industrial site the groundwater contained up to 1000 mg N l(-1) ammonium (NH4(+)) and 300 mg N l(-1) nitrate (NO3(-)), while downgradient concentrations decreased to ∼1 mg l(-1) DIN ([DIN] = [NH4(+)N] + [NO3(-)N] + [NO2(-)N]). Mean δ(15)N-DIN increased from ∼2‰ to +20‰ over this flow path, broadly confirming that biological N attenuation drove the measured concentration decrease. Multi-variate analysis of water chemistry identified two distinct NH4(+) sources (δ(15)NNH4(+) from -14‰ and +5‰) within the contaminated zone of both aquifers. Nitrate dual isotopes co-varied (δ(15)N: -3‰ - +60‰; δ(18)O: 0‰ - +50‰) within the range expected for coupled nitrification and denitrification of the identified sources. The fact that δ(15)NNO2(-) values were 50‰-20‰ less than δ(15)NNH4(+) values in the majority of wells confirmed that nitrification controlled N turnover across the site. However, the fact that δ(15)NNO2(-) was greater than δ(15)NNH4(+) in wells with the highest [NH4(+)] shows that an autotrophic NO2(-) reduction pathway (anaerobic NH4(+) oxidation or nitrifier-denitrification) drove N attenuation closest to the contaminant plume. This direct empirical evidence that both autotrophic and heterotrophic biogeochemical processes drive N attenuation in contaminated aquifers demonstrates the power of multiple N isotopes to untangle N cycling in highly complex systems.
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Affiliation(s)
- Naomi S Wells
- Department of Catchment Hydrology, Helmholtz Centre for Environmental Research - UFZ, Theodor-Lieser Str. 4, 06112 Halle (Saale), Germany.
| | - Vivien Hakoun
- Université de Liège, Département ArGEnCo, Hydrogéologie et Géologie de l'Environnement, Bât. B52/3 - Sart-Tilman, B-4000 Liege, Belgium
| | - Serge Brouyère
- Université de Liège, Département ArGEnCo, Hydrogéologie et Géologie de l'Environnement, Bât. B52/3 - Sart-Tilman, B-4000 Liege, Belgium
| | - Kay Knöller
- Department of Catchment Hydrology, Helmholtz Centre for Environmental Research - UFZ, Theodor-Lieser Str. 4, 06112 Halle (Saale), Germany
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Jung J, Jang IA, Ahn S, Shin B, Kim J, Park C, Jee SC, Sung JS, Park W. Molecular Mechanisms of Enhanced Bacterial Growth on Hexadecane with Red Clay. MICROBIAL ECOLOGY 2015; 70:912-921. [PMID: 25956940 DOI: 10.1007/s00248-015-0624-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 04/27/2015] [Indexed: 06/04/2023]
Abstract
Red clay was previously used to enhance bioremediation of diesel-contaminated soil. It was speculated that the enhanced degradation of diesel was due to increased bacterial growth. In this study, we selected Acinetobacter oleivorans DR1, a soil-borne degrader of diesel and alkanes, as a model bacterium and performed transcriptional analysis using RNA sequencing to investigate the cellular response during hexadecane utilization and the mechanism by which red clay promotes hexadecane degradation. We confirmed that red clay promotes the growth of A. oleivorans DR1 on hexadecane, a major component of diesel, as a sole carbon source. Addition of red clay to hexadecane-utilizing DR1 cells highly upregulated β-oxidation, while genes related to alkane oxidation were highly expressed with and without red clay. Red clay also upregulated genes related to oxidative stress defense, such as superoxide dismutase, catalase, and glutaredoxin genes, suggesting that red clay supports the response of DR1 cells to oxidative stress generated during hexadecane utilization. Increased membrane fluidity in the presence of red clay was confirmed by fatty acid methyl ester analysis at different growth phases, suggesting that enhanced growth on hexadecane could be due to increased uptake of hexadecane coupled with upregulation of downstream metabolism and oxidative stress defense. The monitoring of the bacterial community in soil with red clay for a year revealed that red clay stabilized the community structure.
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Affiliation(s)
- Jaejoon Jung
- Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 136-713, Republic of Korea
| | - In-Ae Jang
- Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 136-713, Republic of Korea
| | - Sungeun Ahn
- Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 136-713, Republic of Korea
| | - Bora Shin
- Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 136-713, Republic of Korea
| | - Jisun Kim
- Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 136-713, Republic of Korea
| | - Chulwoo Park
- Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 136-713, Republic of Korea
| | - Seung Cheol Jee
- Department of Life Science, Dongguk University, Seoul, 100-715, Republic of Korea
| | - Jung-Suk Sung
- Department of Life Science, Dongguk University, Seoul, 100-715, Republic of Korea
| | - Woojun Park
- Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 136-713, Republic of Korea.
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Ponsin V, Maier J, Guelorget Y, Hunkeler D, Bouchard D, Villavicencio H, Höhener P. Documentation of time-scales for onset of natural attenuation in an aquifer treated by a crude-oil recovery system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 512-513:62-73. [PMID: 25617779 DOI: 10.1016/j.scitotenv.2015.01.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 01/13/2015] [Accepted: 01/13/2015] [Indexed: 06/04/2023]
Abstract
A pipeline transporting crude-oil broke in a nature reserve in 2009 and spilled 5100 m(3) of oil that partly reached the aquifer and formed progressively a floating oil lens. Groundwater monitoring started immediately after the spill and crude-oil recovery by dual pump-and-skim technology was operated after oil lens formation. This study aimed at documenting the implementation of redox-specific natural attenuation processes in the saturated zone and at assessing whether dissolved compounds were degraded. Seven targeted water sampling campaigns were done during four years in addition to a routine monitoring of hydrocarbon concentrations. Liquid oil reached the aquifer within 2.5 months, and anaerobic processes, from denitrification to reduction of sulfate, were observable after 8 months. Methanogenesis appeared on site after 28 months. Stable carbon isotope analyses after 16 months showed maximum shifts in δ(13)C of +4.9±0.22‰ for toluene, +2.4±0.19‰ for benzene and +0.9±0.51‰ for ethylbenzene, suggesting anaerobic degradation of these compounds in the source zone. Estimations of fluxes of inorganic carbon produced by biodegradation revealed that, in average, 60% of inorganic carbon production was attributable to sulfate reduction. This percentage tended to decrease with time while the production of carbon attributable to methanogenesis was increasing. Within the investigation time frame, mass balance estimations showed that biodegradation is a more efficient process for control of dissolved concentrations compared to pumping and filtration on an activated charcoal filter.
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Affiliation(s)
- Violaine Ponsin
- Aix-Marseille Université-CNRS, Laboratoire Chimie Environnement FRE, 3416 Marseille, France; French Environment and Energy Management Agency, 20 avenue de Grésillé, BP 90406 Angers Cedex 01, France
| | - Joachim Maier
- ICF Environnement, 14/30 rue Alexandre Bâtiment C F, 92635 Gennevilliers, France
| | - Yves Guelorget
- ICF Environnement, 14/30 rue Alexandre Bâtiment C F, 92635 Gennevilliers, France
| | - Daniel Hunkeler
- Centre for Hydrogeology, University of Neuchâtel, Rue Emile-Argand 11, CH-2000 Neuchâtel, Switzerland
| | - Daniel Bouchard
- Centre for Hydrogeology, University of Neuchâtel, Rue Emile-Argand 11, CH-2000 Neuchâtel, Switzerland
| | - Hakeline Villavicencio
- Centre for Hydrogeology, University of Neuchâtel, Rue Emile-Argand 11, CH-2000 Neuchâtel, Switzerland
| | - Patrick Höhener
- Aix-Marseille Université-CNRS, Laboratoire Chimie Environnement FRE, 3416 Marseille, France.
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