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Prasetyo E, Toyoda K. Humic acid attachment on chitosan-modified silica gel as an economical, efficient, and selective adsorbent for thorium and uranium removal. ENVIRONMENTAL TECHNOLOGY 2023; 44:170-184. [PMID: 34384343 DOI: 10.1080/09593330.2021.1968038] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 07/18/2021] [Indexed: 06/13/2023]
Abstract
A novel, low-cost adsorbent material was prepared by the immobilization of humic acid on a silica gel surface coated with cross-linked chitosan (SiChiHA). The adsorbent was developed to remove selectively of Th(IV) and U(VI) from aqueous solution, including their pre-concentration and separation from lanthanides and high salinity conditions. A simple waste-less humic acid immobilization method was shown to be successful based on FT-IR, SEM-EDS, and zeta potential characterization results. The adsorbent was found to be stable over a wide pH range, with the highest capacities obtained at pH 3.5 (Th(IV)) and pH 5 (U(VI)). Langmuir model calculations yielded a maximum capacity of 30.6 mg g-1 and 75.4 mg g-1 for Th(IV) and U(VI). The adsorption process was found to be rapid (half concentration was removed within 10 min) and best described by a pseudo-second order rate equation. Increasing NaCl concentration up to 2 mol L-1 or lanthanide concentration up to 100 times did not significantly affect the removal efficiency for either Th(IV) of U(VI). Both elements could be sequentially separated by elution with ammonium citrate and nitric acid, respectively. The adsorption-desorption experiment showed that the adsorbent could be used for at least five cycles without significant capacity loss. This study provides insight into the development of low-cost adsorbent with practical functionality, including separation and regeneration ability, the advantageous properties scarcely reported in low-cost adsorbent literature.
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Affiliation(s)
- Erik Prasetyo
- Graduate School of Environmental Science (GSES), Hokkaido University, Sapporo, Japan
- Research Unit for Mineral Technology, Indonesian Institute of Sciences, Bandar Lampung, Indonesia
| | - Kazuhiro Toyoda
- Graduate School of Environmental Science (GSES), Hokkaido University, Sapporo, Japan
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan
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2
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Paradis CJ, Hoss KN, Meurer CE, Hatami JL, Dangelmayr MA, Tigar AD, Johnson RH. Elucidating mobilization mechanisms of uranium during recharge of river water to contaminated groundwater. JOURNAL OF CONTAMINANT HYDROLOGY 2022; 251:104076. [PMID: 36148719 DOI: 10.1016/j.jconhyd.2022.104076] [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: 06/08/2022] [Revised: 08/13/2022] [Accepted: 09/06/2022] [Indexed: 06/16/2023]
Abstract
The recharge of stream water below the baseflow water table can mobilize groundwater contaminants, particularly redox-sensitive and sorptive metals such as uranium. However, in-situ tracer experiments that simulate the recharge of stream water to uranium-contaminated groundwater are lacking, thus limiting the understanding of the potential mechanisms that control the mobility of uranium at the field scale. In this study, a field tracer test was conducted by injecting 100 gal (379 l) of oxic river water into a nearby suboxic and uranium-contaminated aquifer. The traced river water was monitored for 18 days in the single injection well and in the twelve surrounding observation wells. Mobilization of uranium from the solid to the aqueous phase was not observed during the tracer test despite its pre-test presence being confirmed on the aquifer sediments from lab-based acid leaching. However, strong evidence of oxidative immobilization of iron and manganese was observed during the tracer test and suggested that immobile uranium was likely in its oxidized state as U(VI) on the aquifer sediments; these observations ruled out oxidation of U(IV) to U(VI) as a potential mobilization mechanism. Therefore, desorption of U(VI) appeared to be the predominant potential mobilization mechanism, yet it was clearly not solely dependent on concentration as evident when considering that uranium-poor river water (<0.015 mg/L) was recharged to uranium-rich groundwater (≈1 mg/L). It was possible that uranium desorption was limited by the relatively higher pH and lower alkalinity of the river water as compared to the groundwater; both factors favor immobilization. However, it was likely that the immobile uranium was associated with a mineral phase, as opposed to a sorbed phase, thus desorption may not have been possible. The results of this field tracer study successfully ruled out two common mobilization mechanisms of uranium: (1) oxidative dissolution and (2) concentration-dependent desorption and ruled in the importance of advection, dispersion, and the mineral phase of uranium.
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Affiliation(s)
- Charles J Paradis
- Department of Geosciences, University of Wisconsin at Milwaukee, Milwaukee, WI, USA.
| | - Kendyl N Hoss
- Department of Geosciences, University of Wisconsin at Milwaukee, Milwaukee, WI, USA
| | - Cullen E Meurer
- Department of Geosciences, University of Wisconsin at Milwaukee, Milwaukee, WI, USA
| | - Jiyan L Hatami
- Department of Geosciences, University of Wisconsin at Milwaukee, Milwaukee, WI, USA
| | - Martin A Dangelmayr
- Department of Geosciences, University of Wisconsin at Milwaukee, Milwaukee, WI, USA
| | - Aaron D Tigar
- RSI EnTech, LLC, US Department of Energy Office of Legacy Management Support Contractor, Grand Junction, CO, USA
| | - Raymond H Johnson
- RSI EnTech, LLC, US Department of Energy Office of Legacy Management Support Contractor, Grand Junction, CO, USA
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Thompson CC, Lai RY. Threonine Phosphorylation of an Electrochemical Peptide-Based Sensor to Achieve Improved Uranyl Ion Binding Affinity. BIOSENSORS 2022; 12:961. [PMID: 36354470 PMCID: PMC9688285 DOI: 10.3390/bios12110961] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 10/25/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
We have successfully designed a uranyl ion (U(VI)-specific peptide and used it in the fabrication of an electrochemical sensor. The 12-amino acid peptide sequence, (n) DKDGDGYIpTAAE (c), originates from calmodulin, a Ca(II)-binding protein, and contains a phosphothreonine that enhances the sequence's affinity for U(VI) over Ca(II). The sensing mechanism of this U(VI) sensor is similar to other electrochemical peptide-based sensors, which relies on the change in the flexibility of the peptide probe upon interacting with the target. The sensor was systematically characterized using alternating current voltammetry (ACV) and cyclic voltammetry. Its limit of detection was 50 nM, which is lower than the United States Environmental Protection Agency maximum contaminant level for uranium. The signal saturation time was ~40 min. In addition, it showed minimal cross-reactivity when tested against nine different metal ions, including Ca(II), Mg(II), Pb(II), Hg(II), Cu(II), Fe(II), Zn(II), Cd(II), and Cr(VI). Its reusability and ability to function in diluted aquifer and drinking water samples were further confirmed and validated. The response of the sensor fabricated with the same peptide sequence but with a nonphosphorylated threonine was also analyzed, substantiating the positive effects of threonine phosphorylation on U(VI) binding. This study places emphasis on strategic utilization of non-standard amino acids in the design of metal ion-chelating peptides, which will further diversify the types of peptide recognition elements available for metal ion sensing applications.
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Putt AD, Rafie SAA, Hazen TC. Large-Data Omics Approaches in Modern Remediation. JOURNAL OF ENVIRONMENTAL ENGINEERING 2022; 148. [DOI: 10.1061/(asce)ee.1943-7870.0002042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 04/26/2022] [Indexed: 09/02/2023]
Affiliation(s)
- Andrew D. Putt
- Ph.D. Candidate, Dept. of Earth and Planetary Sciences, Univ. of Tennessee, Knoxville, TN 37996. ORCID:
| | - Sa’ad Abd Ar Rafie
- Ph.D. Candidate, Dept. of Civil and Environmental Sciences, Univ. of Tennessee, Knoxville, TN 37996
| | - Terry C. Hazen
- Governor’s Chair Professor, Dept. of Earth and Planetary Sciences, Univ. of Tennessee, Knoxville, TN 37996; Dept. of Civil and Environmental Sciences, Univ. of Tennessee, Knoxville, TN 37996; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831; Dept. of Microbiology, Univ. of Tennessee, Knoxville, TN 37996; Institute for a Secure and Sustainable Environment, Univ. of Tennessee, Knoxville, TN 37996 (corresponding author). ORCID:
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5
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Paradis CJ, Miller JI, Moon J, Spencer SJ, Lui LM, Van Nostrand JD, Ning D, Steen AD, McKay LD, Arkin AP, Zhou J, Alm EJ, Hazen TC. Sustained Ability of a Natural Microbial Community to Remove Nitrate from Groundwater. GROUND WATER 2022; 60:99-111. [PMID: 34490626 PMCID: PMC9290691 DOI: 10.1111/gwat.13132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/24/2021] [Accepted: 08/30/2021] [Indexed: 05/23/2023]
Abstract
Microbial-mediated nitrate removal from groundwater is widely recognized as the predominant mechanism for nitrate attenuation in contaminated aquifers and is largely dependent on the presence of a carbon-bearing electron donor. The repeated exposure of a natural microbial community to an electron donor can result in the sustained ability of the community to remove nitrate; this phenomenon has been clearly demonstrated at the laboratory scale. However, in situ demonstrations of this ability are lacking. For this study, ethanol (electron donor) was repeatedly injected into a groundwater well (treatment) for six consecutive weeks to establish the sustained ability of a microbial community to remove nitrate. A second well (control) located upgradient was not injected with ethanol during this time. The treatment well demonstrated strong evidence of sustained ability as evident by ethanol, nitrate, and subsequent sulfate removal up to 21, 64, and 68%, respectively, as compared to the conservative tracer (bromide) upon consecutive exposures. Both wells were then monitored for six additional weeks under natural (no injection) conditions. During the final week, ethanol was injected into both treatment and control wells. The treatment well demonstrated sustained ability as evident by ethanol and nitrate removal up to 20 and 21%, respectively, as compared to bromide, whereas the control did not show strong evidence of nitrate removal (5% removal). Surprisingly, the treatment well did not indicate a sustained and selective enrichment of a microbial community. These results suggested that the predominant mechanism(s) of sustained ability likely exist at the enzymatic- and/or genetic-levels. The results of this study demonstrated the in situ ability of a microbial community to remove nitrate can be sustained in the prolonged absence of an electron donor.
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Affiliation(s)
- Charles J. Paradis
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
| | - John I. Miller
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
- Bredesen CenterUniversity of TennesseeKnoxvilleTN
| | - Ji‐Won Moon
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
| | - Sarah J. Spencer
- Biological Engineering DepartmentMassachusetts Institute of TechnologyCambridgeMA
| | - Lauren M. Lui
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA
| | - Joy D. Van Nostrand
- Institute for Environmental Genomics, Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental Sciences, University of OklahomaNormanOK
| | - Daliang Ning
- Institute for Environmental Genomics, Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental Sciences, University of OklahomaNormanOK
| | - Andrew D. Steen
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Department of MicrobiologyUniversity of TennesseeKnoxvilleTN
| | - Larry D. McKay
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
| | - Adam P. Arkin
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA
- Department of BioengineeringUniversity of CaliforniaBerkeleyCA
| | - Jizhong Zhou
- Institute for Environmental Genomics, Department of Microbiology and Plant Biologyand School of Civil Engineering and Environmental Sciences, University of OklahomaNormanOK
| | - Eric J. Alm
- Biological Engineering DepartmentMassachusetts Institute of TechnologyCambridgeMA
| | - Terry C. Hazen
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
- Bredesen CenterUniversity of TennesseeKnoxvilleTN
- Department of BioengineeringUniversity of CaliforniaBerkeleyCA
- Department of Civil and Environmental SciencesUniversity of TennesseeKnoxvilleTN
- Center for Environmental BiotechnologyUniversity of TennesseeKnoxvilleTN
- Institute for a Secure and Sustainable EnvironmentUniversity of TennesseeKnoxvilleTN
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Punia A, Bharti R, Kumar P. Hydrogeochemical Processes Governing Uranium Mobility: Inferences from the Anthropogenically Disturbed, Semi-arid Region of India. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2021; 81:386-396. [PMID: 34347119 DOI: 10.1007/s00244-021-00879-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
Khetri Copper Belt, Rajasthan, is anthropogenically active and geologically belongs to the Delhi super-group. A study was designed to understand the geochemical processes controlling the elemental mobility in the groundwater. Sampling sites were divided into three zones, i.e. copper, quartzite and granite mine zones depending on the type of mineral excavated. A total of 32 representative groundwater samples were collected and analysed for heavy metals and radionuclide (U) using ICP-MS. A maximum U concentration (average 87 µgL-1) is observed in the quartzite mine zone, and minimum (average 13 µgL-1) is found in the copper mine zone samples. A high concentration of U (maximum of 430 µgL-1) in groundwater is attributed to mineral dissolution due to geogenic and anthropogenic activities. Despite the presence of Jaspura and Gothra granitoid in the copper mine zone, the abundance of U is low suggesting the scavenging of U by sulphides or iron oxides. Additionally, at the confluence of two geological groups, Fe concentration is found high with a low concentration of U which further confirms scavenging of U. It is evident from the results that in the absence of iron-bearing sulphides, U concentration in groundwater would be very high compared to the current concentration. It also indicates low concentration of U in the copper mine zone is due to dissolution of Fe sulphide-rich waste. The present study recommends further research to understand the feasibility of mining waste for the removal of U contamination from groundwater.
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Affiliation(s)
- Anita Punia
- Department of Civil Engineering, Indian Institute of Technology, Guwahati, India.
| | - Rishikesh Bharti
- Department of Civil Engineering, Indian Institute of Technology, Guwahati, India.
| | - Pankaj Kumar
- Inter-University Accelerator Centre (IUAC), New Delhi, India
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Lui LM, Majumder ELW, Smith HJ, Carlson HK, von Netzer F, Fields MW, Stahl DA, Zhou J, Hazen TC, Baliga NS, Adams PD, Arkin AP. Mechanism Across Scales: A Holistic Modeling Framework Integrating Laboratory and Field Studies for Microbial Ecology. Front Microbiol 2021; 12:642422. [PMID: 33841364 PMCID: PMC8024649 DOI: 10.3389/fmicb.2021.642422] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 02/22/2021] [Indexed: 11/13/2022] Open
Abstract
Over the last century, leaps in technology for imaging, sampling, detection, high-throughput sequencing, and -omics analyses have revolutionized microbial ecology to enable rapid acquisition of extensive datasets for microbial communities across the ever-increasing temporal and spatial scales. The present challenge is capitalizing on our enhanced abilities of observation and integrating diverse data types from different scales, resolutions, and disciplines to reach a causal and mechanistic understanding of how microbial communities transform and respond to perturbations in the environment. This type of causal and mechanistic understanding will make predictions of microbial community behavior more robust and actionable in addressing microbially mediated global problems. To discern drivers of microbial community assembly and function, we recognize the need for a conceptual, quantitative framework that connects measurements of genomic potential, the environment, and ecological and physical forces to rates of microbial growth at specific locations. We describe the Framework for Integrated, Conceptual, and Systematic Microbial Ecology (FICSME), an experimental design framework for conducting process-focused microbial ecology studies that incorporates biological, chemical, and physical drivers of a microbial system into a conceptual model. Through iterative cycles that advance our understanding of the coupling across scales and processes, we can reliably predict how perturbations to microbial systems impact ecosystem-scale processes or vice versa. We describe an approach and potential applications for using the FICSME to elucidate the mechanisms of globally important ecological and physical processes, toward attaining the goal of predicting the structure and function of microbial communities in chemically complex natural environments.
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Affiliation(s)
- Lauren M. Lui
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Erica L.-W. Majumder
- Department of Bacteriology, University of Wisconsin–Madison, Madison, WI, United States
| | - Heidi J. Smith
- Center for Biofilm Engineering, Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - Hans K. Carlson
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Frederick von Netzer
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, United States
| | - Matthew W. Fields
- Center for Biofilm Engineering, Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - David A. Stahl
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, United States
| | - Jizhong Zhou
- Institute for Environmental Genomics, Department of Microbiology & Plant Biology, School of Civil Engineering and Environmental Sciences, University of Oklahoma, Norman, OK, United States
| | - Terry C. Hazen
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, Knoxville, TN, United States
| | | | - Paul D. Adams
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, United States
| | - Adam P. Arkin
- Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, United States
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8
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Bonotto DM, Wijesiri B, Goonetilleke A. Nitrate-dependent Uranium mobilisation in groundwater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 693:133655. [PMID: 31635015 DOI: 10.1016/j.scitotenv.2019.133655] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 07/27/2019] [Accepted: 07/27/2019] [Indexed: 06/10/2023]
Abstract
Nitrate is a critical substance that determines the prevailing redox conditions in groundwater, and in turn the behaviour of Uranium (U). Therefore, the excessive use of nitrate-fertiliser in agricultural catchments could exert a significant influence on U mobilisation. This is a significant issue in catchments, where groundwater resources are increasingly being exploited for drinking water production. Past studies on U mobility in groundwater have considered individual hydro-geochemical factors influencing U concentrations, rather than as a single system with multiple factors. This research study investigated nitrate-dependent U mobility within a catchment in Brazil, where a range of intensive agricultural activities are undertaken and the giant Guarani aquifer is located. The study used direct measurements of groundwater redox conditions and other hydro-geochemical parameters. The research outcomes indicated that U could have two hydro-geochemical systems based on positive and negative redox potential of groundwater. The pH, HCO3- and temperature pose the largest influence, respectively, on U mobilisation, and these impacts are greater in agricultural lands than urban areas. Acidic and less reducing (positive redox) groundwater across the aquifer and basic and highly reducing (negative redox) groundwater in agricultural areas make U more mobile. The alkalinity increases U mobility in less reducing groundwater across the aquifer and in highly reducing groundwater in agricultural areas. Further, U can be mobile in hot and less reducing groundwater across the aquifer, but hot and highly reducing groundwater in agricultural areas can limit U mobility. More importantly, the study revealed that U can be mobile under high NO3- concentrations in reducing groundwater in non-agricultural areas. However, anthropogenic inputs of NO3- are expected to be lower than natural NO3- inputs in areas where the groundwater is highly reducing. Hence, fertiliser use in agricultural lands is less likely to increase U mobility in highly reducing groundwater.
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Affiliation(s)
- Daniel Marcos Bonotto
- Departamento de Petrologia e Metalogenia, Universidade Estadual Paulista (UNESP), Câmpus de Rio Claro, Av. 24-ANo.1515, C.P. 178, CEP 13506-900 Rio Claro, São Paulo, Brazil.
| | - Buddhi Wijesiri
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China; Science and Engineering Faculty, Queensland University of Technology (QUT), GPO Box 2434, Brisbane, Qld 4001, Australia.
| | - Ashantha Goonetilleke
- Science and Engineering Faculty, Queensland University of Technology (QUT), GPO Box 2434, Brisbane, Qld 4001, Australia.
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Li PS, Wu WM, Phillips DH, Watson DB, Kelly S, Li B, Mehlhorn T, Lowe K, Earles J, Tao HC, Zhang T, Criddle CS. Uranium sequestration in sediment at an iron-rich contaminated site at Oak Ridge, Tennessee via. bioreduction followed by reoxidation. J Environ Sci (China) 2019; 85:156-167. [PMID: 31471022 DOI: 10.1016/j.jes.2019.05.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 05/29/2019] [Accepted: 05/30/2019] [Indexed: 06/10/2023]
Abstract
This study evaluated uranium sequestration performance in iron-rich (30 g/kg) sediment via bioreduction followed by reoxidation. Field tests (1383 days) at Oak Ridge, Tennessee demonstrated that uranium contents in sediments increased after bioreduced sediments were re-exposed to nitrate and oxygen in contaminated groundwater. Bioreduction of contaminated sediments (1200 mg/kg U) with ethanol in microcosm reduced aqueous U from 0.37 to 0.023 mg/L. Aliquots of the bioreduced sediment were reoxidized with O2, H2O2, and NaNO3, respectively, over 285 days, resulting in aqueous U of 0.024, 1.58 and 14.4 mg/L at pH 6.30, 6.63 and 7.62, respectively. The source- and the three reoxidized sediments showed different desorption and adsorption behaviors of U, but all fit a Freundlich model. The adsorption capacities increased sharply at pH 4.5 to 5.5, plateaued at pH 5.5 to 7.0, then decreased sharply as pH increased from 7.0 to 8.0. The O2-reoxidized sediment retained a lower desorption efficiency at pH over 6.0. The NO3--reoxidized sediment exhibited higher adsorption capacity at pH 5.5 to 6.0. The pH-dependent adsorption onto Fe(III) oxides and formation of U coated particles and precipitates resulted in U sequestration, and bioreduction followed by reoxidation can enhance the U sequestration in sediment.
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Affiliation(s)
- Peng-Song Li
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Center for Sustainable Development & Global Competitiveness, Stanford University, Stanford, CA 94305-4020, USA; Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Institute of New Energy Technology, Tsinghua University, Beijing 100084, China
| | - Wei-Min Wu
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Center for Sustainable Development & Global Competitiveness, Stanford University, Stanford, CA 94305-4020, USA.
| | - Debra H Phillips
- School of Natural and Built Environment, Queen's University Belfast, Belfast BT9 5AG, Northern Ireland, UK
| | - David B Watson
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA
| | | | - Bing Li
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Center for Sustainable Development & Global Competitiveness, Stanford University, Stanford, CA 94305-4020, USA; Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA; Department of Civil Engineering, The University of Hong Kong, Hong Kong, China
| | - Tonia Mehlhorn
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA
| | - Kenneth Lowe
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA
| | - Jennifer Earles
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, P.O. Box 2008, TN 37831, USA
| | - Hu-Chun Tao
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Tong Zhang
- Department of Civil Engineering, The University of Hong Kong, Hong Kong, China
| | - Craig S Criddle
- Department of Civil and Environmental Engineering, William & Cloy Codiga Resource Recovery Center, Center for Sustainable Development & Global Competitiveness, Stanford University, Stanford, CA 94305-4020, USA.
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10
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Noël V, Boye K, Kukkadapu RK, Li Q, Bargar JR. Uranium storage mechanisms in wet-dry redox cycled sediments. WATER RESEARCH 2019; 152:251-263. [PMID: 30682569 DOI: 10.1016/j.watres.2018.12.040] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 11/30/2018] [Accepted: 12/01/2018] [Indexed: 06/09/2023]
Abstract
Biogeochemical redox processes that govern radionuclide mobility in sediments are highly sensitive to forcing by the water cycle. For example, episodic draining and intrusion of oxidants into reduced zones during dry seasons can create biogeochemical seasonal hotspots of enhanced and changed microbial activity, affect the redox status of minerals, initiate changes in sediment gas and water transport, and stimulate the release of organic carbon, iron, and sulfur by oxidation of solid reduced species to aqueous oxic species. In the Upper Colorado River Basin, water-saturation of organic-enriched sediments locally promotes reducing conditions, denoted 'Naturally Reduced Zones' (NRZs), that accumulate strongly U(IV)sol. Subsequently, fluctuating hydrological conditions introduce oxidants, which may reach internal portions of these sediments and reverse their role to become secondary sources of Uaq. Knowledge of the impact of hydrological variability on the alternating import and export of contaminants, including U, is required to predict contaminant mobility and short- and long-term impacts on water quality. In this study, we tracked U, Fe, and S oxidation states and speciation to characterize the variability in redox processes and related Usol solubility within shallow fine-grained NRZs at the legacy U ore processing site at Shiprock, NM. Previous studies have reported U speciation and behavior in permanently saturated fine-grained NRZ sediments. This is the first report of U behavior in fine-grained NRZ-like sediments that experience repeated redox cycling due to seasonal fluctuations in moisture content. Our results support previous observations that reducing conditions are needed to accumulate Usol in sediments, but they counter the expectation that Usol predominantly accumulates as U(IV)sol; our data reveal that Usol may accumulate as U(VI)sol in roughly equal proportion to U(IV)sol. Surprisingly high abundances of U(VI)sol confined in transiently saturated fine-grained NRZ-like sediments suggest that redox cycling is needed to promote its accumulation. We propose a new process model, where redox oscillations driven by annual water table fluctuations, accompanied by strong evapotranspiration in low-permeability sediments, promote conversion of U(IV)sol to relatively immobile U(VI)sol, which suggests that Usol is accumulating in a form that is resistant to redox perturbations. This observation contradicts the common idea that U(IV)sol accumulated in reducing conditions is systematically re-oxidized, solubilized and transported away in groundwater.
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Affiliation(s)
- Vincent Noël
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, United States
| | - Kristin Boye
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, United States
| | - Ravi K Kukkadapu
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, 99354, United States
| | - Qingyun Li
- Department of Environmental Earth System Science, Stanford University, Stanford, CA, 94305, United States
| | - John R Bargar
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, United States.
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11
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Paradis CJ, Dixon ER, Lui LM, Arkin AP, Parker JC, Istok JD, Perfect E, McKay LD, Hazen TC. Improved Method for Estimating Reaction Rates During Push-Pull Tests. GROUND WATER 2019; 57:292-302. [PMID: 29656383 PMCID: PMC7379995 DOI: 10.1111/gwat.12770] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 04/05/2018] [Accepted: 04/08/2018] [Indexed: 05/30/2023]
Abstract
The breakthrough curve obtained from a single-well push-pull test can be adjusted to account for dilution of the injection fluid in the aquifer fluid. The dilution-adjusted breakthrough curve can be analyzed to estimate the reaction rate of a solute. The conventional dilution-adjusted method assumes that the ratios of the concentrations of the nonreactive and reactive solutes in the injection fluid vs. the aquifer fluid are equal. If this assumption is invalid, the conventional method will generate inaccurate breakthrough curves and may lead to erroneous conclusions regarding the reactivity of a solute. In this study, a new method that generates a dilution-adjusted breakthrough curve was theoretically developed to account for any possible combination of nonreactive and reactive solute concentrations in the injection and aquifer fluids. The newly developed method was applied to a field-based data set and was shown to generate more accurate dilution-adjusted breakthrough curves. The improved dilution-adjusted method presented here is simple, makes no assumptions regarding the concentrations of the nonreactive and reactive solutes in the injection and aquifer fluids, and easily allows for estimating reaction rates during push-pull tests.
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Affiliation(s)
- Charles J. Paradis
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
| | - Emma R. Dixon
- Department of Civil and Environmental EngineeringUniversity of TennesseeKnoxvilleTN
| | - Lauren M. Lui
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA
| | - Adam P. Arkin
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA
- Department of BioengineeringUniversity of CaliforniaBerkeleyCA
| | - Jack C. Parker
- Department of Civil and Environmental EngineeringUniversity of TennesseeKnoxvilleTN
| | - Jonathan D. Istok
- School of Civil and Construction EngineeringOregon State UniversityCorvallisOR
| | - Edmund Perfect
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
| | - Larry D. McKay
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTN
| | - Terry C. Hazen
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN
- Department of Civil and Environmental EngineeringUniversity of TennesseeKnoxvilleTN
- Department of MicrobiologyUniversity of TennesseeKnoxvilleTN
- Center for Environmental BiotechnologyUniversity of TennesseeKnoxvilleTN
- Institute for a Secure and Sustainable EnvironmentUniversity of TennesseeKnoxvilleTN
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12
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Paradis CJ, Moon JW, Elias DA, McKay LD, Hazen TC. In situ decay of polyfluorinated benzoic acids under anaerobic conditions. JOURNAL OF CONTAMINANT HYDROLOGY 2018; 217:8-16. [PMID: 30201555 DOI: 10.1016/j.jconhyd.2018.08.009] [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: 04/13/2018] [Revised: 08/22/2018] [Accepted: 08/31/2018] [Indexed: 06/08/2023]
Abstract
Polyfluorinated benzoic acids (PBAs) can be used as non-reactive tracers to characterize reactive mass transport mechanisms in groundwater. The use of PBAs as non-reactive tracers assumes that their reactivities are negligible. If this assumption is not valid, PBAs may not be appropriate to use as non-reactive tracers. In this study, the reactivity of two PBAs, 2,6-difluorobenzoic acid (2,6-DFBA) and pentafluorobenzoic acid (PFBA), was tested in situ. A series of two single-well push-pull tests were conducted in two hydrogeologically similar, yet spatially distinct, groundwater monitoring wells. Bromide, 2,6-DFBA, and PFBA were added to the injection fluid and periodically measured in the extraction fluid along with chloride, nitrate, sulfate, and fluoride. Linear regression of the dilution-adjusted breakthrough curves of both PBAs indicated zero-order decay accompanied by nitrate and subsequent sulfate removal. The dilution-adjusted breakthrough curves of chloride, a non-reactive halide similar to bromide, showed no evidence of reactivity. These results strongly suggested that biodegradation of both PBAs occurred under anaerobic conditions. The results of this study implied that PBAs may not be appropriate to use as non-reactive tracers in certain hydrogeologic settings, presumably those where they can serve as carbon and/or electron donors to stimulate microbial activity. Future studies would benefit from using ring-14C-labeled PBAs to determine the fate of carbon combined with microbial analyses to characterize the PBA-degrading members of the microbial community.
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Affiliation(s)
- Charles J Paradis
- University of Tennessee, Department of Earth and Planetary Sciences, Knoxville, TN, USA; Oak Ridge National Laboratory, Biosciences Division, Oak Ridge, TN, USA
| | - Ji-Won Moon
- Oak Ridge National Laboratory, Biosciences Division, Oak Ridge, TN, USA
| | - Dwayne A Elias
- Oak Ridge National Laboratory, Biosciences Division, Oak Ridge, TN, USA
| | - Larry D McKay
- University of Tennessee, Department of Earth and Planetary Sciences, Knoxville, TN, USA
| | - Terry C Hazen
- University of Tennessee, Department of Earth and Planetary Sciences, Knoxville, TN, USA; Oak Ridge National Laboratory, Biosciences Division, Oak Ridge, TN, USA; University of Tennessee, Department of Civil and Environmental Engineering, Knoxville, TN, USA; University of Tennessee, Department of Microbiology, Knoxville, TN, USA; University of Tennessee, Center for Environmental Biotechnology, Knoxville, TN, USA; University of Tennessee, Institute for a Secure and Sustainable Environment, Knoxville, TN, USA.
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13
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Jemison NE, Shiel AE, Johnson TM, Lundstrom CC, Long PE, Williams KH. Field Application of 238U/ 235U Measurements To Detect Reoxidation and Mobilization of U(IV). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:3422-3430. [PMID: 29464949 DOI: 10.1021/acs.est.7b05162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Biostimulation to induce reduction of soluble U(VI) to relatively immobile U(IV) is an effective strategy for decreasing aqueous U(VI) concentrations in contaminated groundwater systems. If oxidation of U(IV) occurs following the biostimulation phase, U(VI) concentrations increase, challenging the long-term effectiveness of this technique. However, detecting U(IV) oxidation through dissolved U concentrations alone can prove difficult in locations with few groundwater wells to track the addition of U to a mass of groundwater. We propose the 238U/235U ratio of aqueous U as an independent, reliable tracer of U(IV) remobilization via oxidation or mobilization of colloids. Reduction of U(VI) produces 238U-enriched U(IV), whereas remobilization of solid U(IV) should not induce isotopic fractionation. The incorporation of remobilized U(IV) with a high 238U/235U ratio into the aqueous U(VI) pool produces an increase in 238U/235U of aqueous U(VI). During several injections of nitrate to induce U(IV) oxidation, 238U/235U consistently increased, suggesting 238U/235U is broadly applicable for detecting mobilization of U(IV).
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Affiliation(s)
- Noah E Jemison
- Department of Geology , University of Illinois at Urbana-Champaign , 3081 Natural History Building, 1301 W. Green St. , Urbana , Illinois 61801 , United States
| | - Alyssa E Shiel
- College of Earth, Ocean, and Atmospheric Sciences , Oregon State University , 104 CEOAS Administration Building, 101 SW 26th St. , Corvallis , Oregon 97331 , United States
| | - Thomas M Johnson
- Department of Geology , University of Illinois at Urbana-Champaign , 3081 Natural History Building, 1301 W. Green St. , Urbana , Illinois 61801 , United States
| | - Craig C Lundstrom
- Department of Geology , University of Illinois at Urbana-Champaign , 3081 Natural History Building, 1301 W. Green St. , Urbana , Illinois 61801 , United States
| | - Philip E Long
- Earth Sciences Division , Lawrence Berkeley National Laboratory , 1 Cyclotron Road , Berkeley , California 94720 , United States
| | - Kenneth H Williams
- Earth Sciences Division , Lawrence Berkeley National Laboratory , 1 Cyclotron Road , Berkeley , California 94720 , United States
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14
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Taylor AE, Bottomley PJ, Semprini L. Contrasting growth properties of Nocardioides JS614 on threedifferent vinyl halides. Appl Microbiol Biotechnol 2018; 102:1859-1867. [PMID: 29297101 DOI: 10.1007/s00253-017-8723-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 12/14/2017] [Accepted: 12/16/2017] [Indexed: 10/18/2022]
Abstract
Ethene (ETH)-grown inocula of Nocardioides JS614 grow on vinyl chloride (VC), vinyl fluoride (VF), or vinyl bromide (VB) as the sole carbon and energy source, with faster growth rates and higher cell yields on VC and VF than on VB. However, whereas acetate-grown inocula of JS614 grow on VC and VF after a lag period, growth on VB did not occur unless supplemental ethene oxide (EtO) was present in the medium. Despite inferior growth on VB, the maximum rate of VB consumption by ETH-grown cells was ~ 50% greater than the rates of VC and VF consumption, but Br- release during VB consumption was non-stoichiometric with VB consumption (~ 66%) compared to 100% release of Cl- and F- during VC and VF consumption. Evidence was obtained for VB turnover-dependent toxicity of cell metabolism in JS614 with both acetate-dependent respiration and growth being significantly reduced by VB turnover, but no VC or VF turnover-dependent toxicity of growth was detected. Reduced growth rate and cell yield of JS614 on VB probably resulted from a combination of inefficient metabolic processing of the highly unstable VB epoxide (t0.5 = 45 s), accompanied by growth inhibitory effects of VB metabolites on acetate-dependent metabolism. The exact role(s) of EtO in promoting growth of alkene repressed JS614 on VB remains unresolved, with evidence of EtO inducing epoxide consuming activity prior to an increase in alkene oxidizing activity and supplementing reductant supply when VB is the growth substrate.
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Affiliation(s)
- Anne E Taylor
- Department of Chemical Biological and Environmental Engineering, Oregon State University, Corvallis, OR, 97331, USA. .,Department of Crop and Soil Science, Oregon State University, Corvallis, OR, 97331, USA. .,Department of Crop and Soil Science, 3017 ALS Building, Oregon State University, Corvallis, OR, 97331, USA.
| | - Peter J Bottomley
- Department of Crop and Soil Science, Oregon State University, Corvallis, OR, 97331, USA
| | - Lewis Semprini
- Department of Chemical Biological and Environmental Engineering, Oregon State University, Corvallis, OR, 97331, USA
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15
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Bone SE, Cahill MR, Jones ME, Fendorf S, Davis J, Williams KH, Bargar JR. Oxidative Uranium Release from Anoxic Sediments under Diffusion-Limited Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:11039-11047. [PMID: 28876920 DOI: 10.1021/acs.est.7b02241] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Uranium (U) contamination occurs as a result of mining and ore processing; often in alluvial aquifers that contain organic-rich, reduced sediments that accumulate tetravalent U, U(IV). Uranium(IV) is sparingly soluble, but may be mobilized upon exposure to nitrate (NO3-) and oxygen (O2), which become elevated in groundwater due to seasonal fluctuations in the water table. The extent to which oxidative U mobilization can occur depends upon the transport properties of the sediments, the rate of U(IV) oxidation, and the availability of inorganic reductants and organic electron donors that consume oxidants. We investigated the processes governing U release upon exposure of reduced sediments to artificial groundwater containing O2 or NO3- under diffusion-limited conditions. Little U was mobilized during the 85-day reaction, despite rapid diffusion of groundwater within the sediments and the presence of nonuraninite U(IV) species. The production of ferrous iron and sulfide in conjunction with rapid oxidant consumption suggested that the sediments harbored large concentrations of bioavailable organic carbon that fueled anaerobic microbial respiration and stabilized U(IV). Our results suggest that seasonal influxes of O2 and NO3- may cause only localized mobilization of U without leading to export of U from the reducing sediments when ample organic carbon is present.
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Affiliation(s)
- Sharon E Bone
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory , Menlo Park, California 94025, United States
| | | | - Morris E Jones
- Stanford University , Stanford, California 94305, United States
| | - Scott Fendorf
- Stanford University , Stanford, California 94305, United States
| | - James Davis
- U.S. Geological Survey, Menlo Park, California 94025, United States
| | - Kenneth H Williams
- Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - John R Bargar
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory , Menlo Park, California 94025, United States
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16
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van Berk W, Fu Y. Redox Roll-Front Mobilization of Geogenic Uranium by Nitrate Input into Aquifers: Risks for Groundwater Resources. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:337-345. [PMID: 28001365 DOI: 10.1021/acs.est.6b01569] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Redox conditions are seen as the key to controlling aqueous uranium concentrations (cU(aq)). Groundwater data collected by a state-wide groundwater quality monitoring study in Mecklenburg-Western Pomerania (Germany) reveal peak cU(aq) up to 75 μg L-1 but low background uranium concentrations (median cU(aq) < 0.5 μg L-1). To characterize the hydrogeochemical processes causing such groundwater contamination by peak cU(aq), we reanalyzed measured redox potentials and total concentrations of aqueous uranium, nitrate, and sulfate species in groundwater together with their distribution across the aquifer depth and performed semigeneric 2D reactive mass transport modeling which is based on chemical thermodynamics. The combined interpretation of modeling results and measured data reveals that high cU(aq) and its depth-specific distribution depending on redox conditions is a result of a nitrate-triggered roll-front mobilization of geogenic uranium in the studied aquifers which are unaffected by nuclear activities. The modeling results show that groundwater recharge containing (fertilizer-derived) nitrate drives the redox shift from originally reducing toward oxidizing environments, when nitrate input has consumed the reducing capacity of the aquifers, which is present as pyrite, degradable organic carbon, and geogenic U(IV) minerals. This redox shift controls the uranium roll-front mobilization and results in high cU(aq) within the redoxcline. Moreover, the modeling results indicate that peak cU(aq) occurring at this redox front increase along with the temporal progress of such redox conversion within the aquifer.
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Affiliation(s)
- Wolfgang van Berk
- Institute of Geology and Paleontology, Clausthal University of Technology , Leibnizstraße 10, 38678 Clausthal-Zellerfeld, Germany
| | - Yunjiao Fu
- Institute of Geology and Paleontology, Clausthal University of Technology , Leibnizstraße 10, 38678 Clausthal-Zellerfeld, Germany
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Techtmann SM, Hazen TC. Metagenomic applications in environmental monitoring and bioremediation. J Ind Microbiol Biotechnol 2016; 43:1345-54. [PMID: 27558781 DOI: 10.1007/s10295-016-1809-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 07/30/2016] [Indexed: 01/08/2023]
Abstract
With the rapid advances in sequencing technology, the cost of sequencing has dramatically dropped and the scale of sequencing projects has increased accordingly. This has provided the opportunity for the routine use of sequencing techniques in the monitoring of environmental microbes. While metagenomic applications have been routinely applied to better understand the ecology and diversity of microbes, their use in environmental monitoring and bioremediation is increasingly common. In this review we seek to provide an overview of some of the metagenomic techniques used in environmental systems biology, addressing their application and limitation. We will also provide several recent examples of the application of metagenomics to bioremediation. We discuss examples where microbial communities have been used to predict the presence and extent of contamination, examples of how metagenomics can be used to characterize the process of natural attenuation by unculturable microbes, as well as examples detailing the use of metagenomics to understand the impact of biostimulation on microbial communities.
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Affiliation(s)
| | - Terry C Hazen
- Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, USA
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