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Lian G, An Y, Sun J, Yang B, Shen Z. Effects and driving mechanisms of bioremediation on groundwater after the neutral in situ leaching of uranium. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 946:174406. [PMID: 38964395 DOI: 10.1016/j.scitotenv.2024.174406] [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: 04/16/2024] [Revised: 06/04/2024] [Accepted: 06/29/2024] [Indexed: 07/06/2024]
Abstract
The remediation of groundwater subject to in situ leaching (ISL) for uranium mining has raised extensive concerns in uranium mill and milling. This study conducted bioremediation through biostimulation and bioaugmentation to the groundwater in an area in northern China that was contaminated due to uranium mining using the CO2 + O2 neutral ISL (NISL) technology. It identified the dominant controlling factors and mechanisms driving bioremediation. Findings indicate that microorganisms can reduce the uranium concentration in groundwater subject to NISL uranium mining to its normal level. After 120 days of bioaugmentation, the uranium concentration in the contaminated groundwater fell to 0.36 mg/L, achieving a remediation efficiency of 91.26 %. Compared with biostimulation, bioaugmentation shortened the remediation timeframe by 30 to 60 days while maintaining roughly the same remediation efficiency. For groundwater remediation using indigenous microbial inoculants, initial uranium concentration and low temperatures (below 15 °C) emerge as the dominant factors influencing the bioremediation performance and duration. In settings with high carbonate concentrations, bioremediation involved the coupling of multiple processes including bioreduction, biotransformation, biomineralization, and biosorption, with bioreduction assuming a predominant role. Post-bioremediation, the relative abundances of reducing microbes Desulfosporosinus and Sulfurospirillum in groundwater increased significantly by 10.56 % and 6.91 %, respectively, offering a sustainable, stable biological foundation for further bioremediation of groundwater.
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Affiliation(s)
- Guoxi Lian
- State Key Laboratory of Water Environment, School of Environment, Beijing Normal University, Beijing 100875, China; Nuclear and Radiation Safety Center, Ministry of Ecology and Environment, Beijing 100082, China
| | - Yifu An
- The Fourth Research and Design Engineering Corporation of CNNC, Shijiazhuang 050021, China
| | - Juan Sun
- The Fourth Research and Design Engineering Corporation of CNNC, Shijiazhuang 050021, China
| | - Bing Yang
- The Fourth Research and Design Engineering Corporation of CNNC, Shijiazhuang 050021, China
| | - Zhenyao Shen
- State Key Laboratory of Water Environment, School of Environment, Beijing Normal University, Beijing 100875, China.
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Howells AP, Lewis SJ, Beard DB, Oliver IW. Water treatment residuals as soil amendments: Examining element extractability, soil porewater concentrations and effects on earthworm behaviour and survival. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 162:334-340. [PMID: 30005406 DOI: 10.1016/j.ecoenv.2018.06.087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 06/27/2018] [Accepted: 06/28/2018] [Indexed: 05/14/2023]
Abstract
Drinking water treatment residuals (WTRs), the by-product of water clarification processes, are routinely disposed of via landfill however there is a growing body of research that demonstrates the material has great potential for beneficial use in environmental applications. Application to agricultural land is one option showing great promise (i.e. a low cost disposal route that provides organic matter input to soils and other potential benefits), however questions remain as to the impact such applications may have on earthworm survival and behaviour and also on the potential effects it may have on soil porewater chemistry. This study examined the leachability of elements within two types of WTRs (one Al- and one Fe- based) from England via 0.001 M CaCl2 solution, at varying pH, and via the Community Bureau of Reference (BCR) sequential extraction scheme. Earthworm avoidance, survival, growth, reproduction and element concentrations were examined in WTR-amended sandy soils (0%, 5%, 10%, 20% w/w), while soil porewaters were also recovered from experimental units and examined for element concentrations. The results revealed leachable element concentrations to be very low in both types of WTRs tested and so element leaching from these WTRs would be unlikely to pose any threat to ecosystems under typical agricultural soil conditions. However, when the pH was lowered to 4.4 there was a substantial release of Al from the Al-WTRs (382 mg/kg). Soil porewater element concentrations were influenced to some degree by WTR addition, warranting further examination in terms of any potential implications for nutrient supply or limitation. Earthworm avoidance of WTR-amended soil was only observed for Al-WTRs and only at the maximum applied rate (20% w/w), while survival of earthworms was not affected by either WTR type at any application rate. Earthworm growth and reproduction (cocoon production) were not affected at a statistically significant level but this needs further examination over a longer period of exposure. Increased assimilation of Al and Fe into earthworm tissues was observed at some WTR application rates (maximum fresh weight concentrations of 42 mg/kg for Al and 167 mg/kg for Fe), but these were not at levels likely to pose environmental concerns.
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Affiliation(s)
- Anthony P Howells
- School of Geography, Geology and the Environment, Keele University, Keele ST5 5BG, United Kingdom
| | - Steven J Lewis
- School of Geography, Geology and the Environment, Keele University, Keele ST5 5BG, United Kingdom
| | - Dylan B Beard
- School of Geography, Geology and the Environment, Keele University, Keele ST5 5BG, United Kingdom
| | - Ian W Oliver
- School of Geography, Geology and the Environment, Keele University, Keele ST5 5BG, United Kingdom.
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Kubrová J, Zigová A, Randa Z, Rohovec J, Gryndler M, Krausová I, Dunn CE, Kotrba P, Borovička J. On the possible role of macrofungi in the biogeochemical fate of uranium in polluted forest soils. JOURNAL OF HAZARDOUS MATERIALS 2014; 280:79-88. [PMID: 25136765 DOI: 10.1016/j.jhazmat.2014.07.050] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 07/09/2014] [Accepted: 07/24/2014] [Indexed: 05/15/2023]
Abstract
Interactions of macrofungi with U, Th, Pb and Ag were investigated in the former ore mining district of Příbram, Czech Republic. Samples of saprotrophic (34 samples, 24 species) and ectomycorrhizal (38 samples, 26 species) macrofungi were collected from a U-polluted Norway spruce plantation and tailings and analyzed for metal content. In contrast to Ag, which was highly accumulated in fruit-bodies, concentrations of U generally did not exceed 3mg/kg which indicates a very low uptake rate and efficient exclusion of U from macrofungi. In ectomycorrhizal tips (mostly determined to species level by DNA sequencing), U contents were practically identical with those of the non-mycorrhizal fine spruce roots. These findings suggest a very limited role of macrofungi in uptake and biotransformation of U in polluted forest soils. Furthermore, accumulation of U, Th, Pb and Ag in macrofungal fruit-bodies apparently does not depend on total content and chemical fractionation of these metals in soils (tested by the BCR sequential extraction in this study).
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Affiliation(s)
- Jaroslava Kubrová
- Institute of Geochemistry, Mineralogy and Mineral Resources, Faculty of Science, Charles University, Albertov 6, CZ-12843 Prague 2, Czech Republic; Nuclear Physics Institute, v.v.i., Academy of Sciences of the Czech Republic, Husinec-Řež 130, CZ-25068 Řež near Prague, Czech Republic
| | - Anna Zigová
- Institute of Geology, v.v.i., Academy of Sciences of the Czech Republic, Rozvojová 269, CZ-16500 Prague 6, Czech Republic
| | - Zdeněk Randa
- Nuclear Physics Institute, v.v.i., Academy of Sciences of the Czech Republic, Husinec-Řež 130, CZ-25068 Řež near Prague, Czech Republic
| | - Jan Rohovec
- Institute of Geology, v.v.i., Academy of Sciences of the Czech Republic, Rozvojová 269, CZ-16500 Prague 6, Czech Republic
| | - Milan Gryndler
- Institute of Microbiology, v.v.i., Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ-142 20 Prague 4, Czech Republic
| | - Ivana Krausová
- Nuclear Physics Institute, v.v.i., Academy of Sciences of the Czech Republic, Husinec-Řež 130, CZ-25068 Řež near Prague, Czech Republic
| | - Colin E Dunn
- 8756 Pender Park Drive, Sidney, BC, V8L 3Z5 Canada
| | - Pavel Kotrba
- Department of Biochemistry and Microbiology, Institute of Chemical Technology, Prague, Technická 3, CZ-166 28 Prague 6, Czech Republic
| | - Jan Borovička
- Nuclear Physics Institute, v.v.i., Academy of Sciences of the Czech Republic, Husinec-Řež 130, CZ-25068 Řež near Prague, Czech Republic; Institute of Geology, v.v.i., Academy of Sciences of the Czech Republic, Rozvojová 269, CZ-16500 Prague 6, Czech Republic.
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Harguindeguy S, Crançon P, Pointurier F, Potin-Gautier M, Lespes G. Isotopic investigation of the colloidal mobility of depleted uranium in a podzolic soil. CHEMOSPHERE 2014; 103:343-348. [PMID: 24387914 DOI: 10.1016/j.chemosphere.2013.12.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 11/30/2013] [Accepted: 12/11/2013] [Indexed: 06/03/2023]
Abstract
The mobility and colloidal migration of uranium were investigated in a soil where limited amounts of anthropogenic uranium (depleted in the 235U isotope) were deposited, adding to the naturally occurring uranium. The colloidal fraction was assumed to correspond to the operational fraction between 10 kDa and 1.2 μm after (ultra)filtration. Experimental leaching tests indicate that approximately 8-15% of uranium is desorbed from the soil. Significant enrichment of the leachate in the depleted uranium (DU) content indicates that uranium from recent anthropogenic DU deposit is weakly bound to soil aggregates and more mobile than geologically occurring natural uranium (NU). Moreover, 80% of uranium in leachates was located in the colloidal fractions. Nevertheless, the percentage of DU in the colloidal and dissolved fractions suggests that NU is mainly associated with the non-mobile coarser fractions of the soil. A field investigation revealed that the calculated percentages of DU in soil and groundwater samples result in the enhanced mobility of uranium downstream from the deposit area. Colloidal uranium represents between 10% and 32% of uranium in surface water and between 68% and 90% of uranium in groundwater where physicochemical parameters are similar to those of the leachates. Finally, as observed in batch leaching tests, the colloidal fractions of groundwater contain slightly less DU than the dissolved fraction, indicating that DU is primarily associated with macromolecules in dissolved fraction.
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Affiliation(s)
- S Harguindeguy
- Université de Pau et des Pays de l'Adour, Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, IPREM-UMR 5254 Pau, France; CEA, DAM, DIF, F-91297 Arpajon, France
| | - P Crançon
- CEA, DAM, DIF, F-91297 Arpajon, France
| | | | - M Potin-Gautier
- Université de Pau et des Pays de l'Adour, Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, IPREM-UMR 5254 Pau, France
| | - G Lespes
- Université de Pau et des Pays de l'Adour, Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, IPREM-UMR 5254 Pau, France.
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Crean DE, Livens FR, Sajih M, Stennett MC, Grolimund D, Borca CN, Hyatt NC. Remediation of soils contaminated with particulate depleted uranium by multi stage chemical extraction. JOURNAL OF HAZARDOUS MATERIALS 2013; 263 Pt 2:382-390. [PMID: 23998894 DOI: 10.1016/j.jhazmat.2013.08.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 07/09/2013] [Accepted: 08/02/2013] [Indexed: 06/02/2023]
Abstract
Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction. Uranium rich particles with characteristic spherical morphologies were observed in soils, consistent with other instances of DU munitions contamination. Batch extraction efficiencies for aqueous ammonium bicarbonate (42-50% total DU extracted), citric acid (30-42% total DU) and sulphuric acid (13-19% total DU) were evaluated. Characterisation of residues from bicarbonate-treated soils by synchrotron microfocus X-ray diffraction and X-ray absorption spectroscopy revealed partially leached U(IV)-oxide particles and some secondary uranyl-carbonate phases. Based on these data, a multi-stage extraction scheme was developed utilising leaching in ammonium bicarbonate followed by citric acid to dissolve secondary carbonate species. Site specific U extraction was improved to 68-87% total U by the application of this methodology, potentially providing a route to efficient DU decontamination using low cost, environmentally compatible reagents.
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Affiliation(s)
- Daniel E Crean
- Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, UK; Centre for Radiochemistry Research, School of Chemistry, The University of Manchester, UK
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Graham MC. Comment on ‘An investigation of the biogeochemistry of the uranium radionuclide in the munitions testing contaminated soil of Kirkcudbright, New Galloway, SW Scotland’, by N. Kumar et al., J. Radioanal. Nucl. Chem., 290 (2011) 203–208. J Radioanal Nucl Chem 2013. [DOI: 10.1007/s10967-012-1903-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Li X, Wu J, Liao J, Zhang D, Yang J, Feng Y, Zeng J, Wen W, Yang Y, Tang J, Liu N. Adsorption and desorption of uranium (VI) in aerated zone soil. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2013; 115:143-150. [PMID: 22939949 DOI: 10.1016/j.jenvrad.2012.08.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 07/09/2012] [Accepted: 08/06/2012] [Indexed: 06/01/2023]
Abstract
In this paper, the adsorption and desorption behavior of uranium (VI) in aerated zone soil (from Southwest China) was systematically investigated using a static experimental method in order to provide useful information for safety assessment of the disposal of (ultra-)low uraniferous radioactive waste, as well as a potential remediation method for uranium-contaminated soils. The adsorption behavior of uranium (VI) was firstly studied by batch experiments as functions of contact time, pH, liquid/solid ratio, temperature, colloids, minerals and coexistent ions. The results indicated that the adsorption of uranium (VI) by natural soil was efficient at an initial concentration of 10 mg/L uranium (VI) nitrate solution with 100 mg natural soil at room temperature when pH is about 7.0. The adsorption was strongly influenced by the solution pH, contact time, initial concentration and colloids. The adsorption equilibrium for uranium (VI) in soil was obtained within 24 h and the process could be described by the Langmuir adsorption equation. For uranium (VI) desorption, EDTA, citric acid and HNO(3) were evaluated under different conditions of temperature, concentration and proportion of liquid to solid. The adsorbed uranium (VI) on natural soil could be easily extracted by all these agents, especially by HNO(3), implying that the uranium-contaminated soils can be remedied by these reagents.
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Affiliation(s)
- Xiaolong Li
- Key Laboratory of Radiation Physics and Technology, Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, PR China
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8
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Brittain SR, Cox AG, Tomos AD, Paterson E, Siripinyanond A, McLeod CW. Chemical speciation studies on DU contaminated soils using flow field flow fractionation linked to inductively coupled plasma mass spectrometry (FlFFF-ICP-MS). ACTA ACUST UNITED AC 2012; 14:782-90. [DOI: 10.1039/c2em10716c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Graham MC, Oliver IW, MacKenzie AB, Ellam RM, Farmer JG. Mechanisms controlling lateral and vertical porewater migration of depleted uranium (DU) at two UK weapons testing sites. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:1854-1866. [PMID: 21345483 DOI: 10.1016/j.scitotenv.2011.01.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Revised: 12/23/2010] [Accepted: 01/06/2011] [Indexed: 05/30/2023]
Abstract
Uranium associations with colloidal and truly dissolved soil porewater components from two Ministry of Defence Firing Ranges in the UK were investigated. Porewater samples from 2-cm depth intervals for three soil cores from each of the Dundrennan and Eskmeals ranges were fractionated using centrifugal ultrafiltration (UF) and gel electrophoresis (GE). Soil porewaters from a transect running downslope from the Dundrennan firing area towards a stream (Dunrod Burn) were examined similarly. Uranium concentrations and isotopic composition were determined using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Multi-Collector-Inductively Coupled Plasma-Mass Spectrometry (MC-ICP-MS), respectively. The soils at Dundrennan were Fe- and Al-rich clay-loam soils whilst at Eskmeals, they were Fe- and Al-poor sandy soils; both, however, had similar organic matter contents due to the presence of a near-surface peaty layer at Eskmeals. These compositional features influenced the porewater composition and indeed the associations of U (and DU). In general, at Dundrennan, U was split between large (100kDa-0.2μm) and small (3-30kDa) organic colloids whilst at Eskmeals, U was mainly in the small colloidal and truly dissolved fractions. Especially below 10cm depth, association with large Fe/Al/organic colloids was considered to be a precursor to the removal of U from the Dundrennan porewaters to the solid phase. In contrast, the association of U with small organic colloids was largely responsible for inhibiting attenuation in the Eskmeals soils. Lateral migration of U (and DU) through near-surface Dundrennan soils will involve both large and small colloids but, at depth, transport of the smaller amounts of U remaining in the porewaters may involve large colloids only. For one of the Dundrennan cores the importance of redox-related processes for the re-mobilisation of DU was also indicated as Mn(IV) reduction resulted in the release of both Mn(II) and U(VI) into the truly dissolved phase.
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Affiliation(s)
- Margaret C Graham
- School of GeoSciences, Crew Building, University of Edinburgh, The King's Buildings, West Mains Road, Edinburgh, EH9 3JN, United Kingdom.
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Sajih M, Livens FR, Alvarez R, Morgan M. Physicochemical characterisation of depleted uranium (DU) particles at a UK firing test range. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:5990-5996. [PMID: 20855109 DOI: 10.1016/j.scitotenv.2010.07.075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 07/21/2010] [Accepted: 07/28/2010] [Indexed: 05/29/2023]
Abstract
Depleted uranium (DU) particles were isolated from soils at Eskmeals, UK, where DU munitions have been tested against hard targets and unfired DU buried in soils for corrosion studies. Using electron microscopy and X-ray analyses, three classes of particles were identified: (1) DU aerosols and fragments, typically 1-20 μm diameter, composed mainly of uranium as UO(2) and U(3)O(8), (2) solidified molten particles, typically 200-500 μm diameter, composed of U, mixed with Fe from target materials and (3) deposits and coatings, often of metaschoepite on sand grains up to 500 μm diameter. The first two particle types are derived from firing impacts, the last from corrosion of buried uranium metal. Alpha and mass spectrometry allowed quantitative elemental and isotopic characterisation of DU-containing particulate environmental samples.
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Affiliation(s)
- Mustafa Sajih
- Centre for Radiochemistry Research, School of Chemistry, University of Manchester, Manchester, M13 9PL, UK.
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Handley-Sidhu S, Keith-Roach MJ, Lloyd JR, Vaughan DJ. A review of the environmental corrosion, fate and bioavailability of munitions grade depleted uranium. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:5690-5700. [PMID: 20858561 DOI: 10.1016/j.scitotenv.2010.08.028] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 08/10/2010] [Accepted: 08/16/2010] [Indexed: 05/29/2023]
Abstract
Depleted uranium (DU) is a by-product of nuclear fuel enrichment and is used in antitank penetrators due to its high density, self-sharpening, and pyrophoric properties. Military activities have left a legacy of DU waste in terrestrial and marine environments, and there have been only limited attempts to clean up affected environments. Ten years ago, very little information was available on the dispersion of DU as penetrators hit their targets or the fate of DU penetrators left behind in environmental systems. However, the marked increase in research since then has improved our knowledge of the environmental impact of firing DU and the factors that control the corrosion of DU and its subsequent migration through the environment. In this paper, the literature is reviewed and consolidated to provide a detailed overview of the current understanding of the environmental behaviour of DU and to highlight areas that need further consideration.
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Affiliation(s)
- Stephanie Handley-Sidhu
- Water Sciences Research Group, School of Geography, Earth, Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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Crançon P, Pili E, Charlet L. Uranium facilitated transport by water-dispersible colloids in field and soil columns. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:2118-2128. [PMID: 20178885 DOI: 10.1016/j.scitotenv.2010.01.061] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Revised: 01/26/2010] [Accepted: 01/27/2010] [Indexed: 05/28/2023]
Abstract
The transport of uranium through a sandy podzolic soil has been investigated in the field and in column experiments. Field monitoring, numerous years after surface contamination by depleted uranium deposits, revealed a 20 cm deep uranium migration in soil. Uranium retention in soil is controlled by the <50 microm mixed humic and clayey coatings in the first 40 cm i.e. in the E horizon. Column experiments of uranium transport under various conditions were run using isotopic spiking. After 100 pore volumes elution, 60% of the total input uranium is retained in the first 2 cm of the column. Retardation factor of uranium on E horizon material ranges from 1300 (column) to 3000 (batch). In parallel to this slow uranium migration, we experimentally observed a fast elution related to humic colloids of about 1-5% of the total-uranium input, transferred at the mean porewater velocity through the soil column. In order to understand the effect of rain events, ionic strength of the input solution was sharply changed. Humic colloids are retarded when ionic strength increases, while a major mobilization of humic colloids and colloid-borne uranium occurs as ionic strength decreases. Isotopic spiking shows that both (238)U initially present in the soil column and (233)U brought by input solution are desorbed. The mobilization process observed experimentally after a drop of ionic strength may account for a rapid uranium migration in the field after a rainfall event, and for the significant uranium concentrations found in deep soil horizons and in groundwater, 1 km downstream from the pollution source.
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Affiliation(s)
- P Crançon
- CEA, DAM, DIF, F-91297 Arpajon, France.
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13
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Rossiter HM, Graham MC, Schäfer AI. Impact of speciation on behaviour of uranium in a solar powered membrane system for treatment of brackish groundwater. Sep Purif Technol 2010. [DOI: 10.1016/j.seppur.2009.11.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lloyd NS, Chenery SRN, Parrish RR. The distribution of depleted uranium contamination in Colonie, NY, USA. THE SCIENCE OF THE TOTAL ENVIRONMENT 2009; 408:397-407. [PMID: 19853279 DOI: 10.1016/j.scitotenv.2009.09.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Revised: 09/11/2009] [Accepted: 09/14/2009] [Indexed: 05/28/2023]
Abstract
Uranium oxide particles were dispersed into the environment from a factory in Colonie (NY, USA) by prevailing winds during the 1960s and '70s. Uranium concentrations and isotope ratios from bulk soil samples have been accurately measured using inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) without the need for analyte separation chemistry. The natural range of uranium concentrations in the Colonie soils has been estimated as 0.7-2.1 microg g(-1), with a weighted geometric mean of 1.05 microg g(-1); the contaminated soil samples comprise uranium up to 500+/-40 microg g(-1). A plot of (236)U/(238)U against (235)U/(238)U isotope ratios describes a mixing line between natural uranium and depleted uranium (DU) in bulk soil samples; scatter from this line can be accounted for by heterogeneity in the DU particulate. The end-member of DU compositions aggregated in these bulk samples comprises (2.05+/-0.06) x 10(-3)(235)U/(238)U, (3.2+/-0.1)x10(-5)(236)U/(238)U, and (7.1+/-0.3) x 10(-6)(234)U/(238)U. The analytical method is sensitive to as little as 50 ng g(-1) DU mixed with the natural uranium occurring in these soils. The contamination footprint has been mapped northward from site, and at least one third of the uranium in a soil sample from the surface 5 cm, collected 5. 1km NNW of the site, is DU. The distribution of contamination within the surface soil horizon follows a trend of exponential decrease with depth, which can be approximated by a simple diffusion model. Bioturbation by earthworms can account for dispersal of contaminant from the soil surface, in the form of primary uranium oxide particulates, and uranyl species that are adsorbed to organic matter. Considering this distribution, the total mass of uranium contamination emitted from the factory is estimated to be c. 4.8 tonnes.
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Affiliation(s)
- N S Lloyd
- Department of Geology, University of Leicester, University Road, Leicester, LE1 7RH, UK.
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Oliver IW, Graham MC, MacKenzie AB, Ellam RM, Farmer JG. Depleted uranium mobility across a weapons testing site: isotopic investigation of porewater, earthworms, and soils. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:9158-9164. [PMID: 19174886 DOI: 10.1021/es8013634] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The mobility and bioavailability of depleted uranium (DU) in soils at a UK Ministry of Defence (UK MoD) weapons testing range were investigated. Soil and vegetation were collected near a test-firing position and at eight points along a transect line extending approximately 200 m down-slope, perpendicular to the firing line, toward a small stream. Earthworms and porewaters were subsequently separated from the soils and both total filtered porewater (<0.2 microm) and discrete size fractions (0.2 microm-100 kDa, 100-30 kDa, 30-3 kDa, and <3 kDa)obtainedvia centrifugal ultrafiltration were examined. Uranium concentrations were determined by inductively coupled plasma optical emission spectrometry (ICP-OES) for soils and ICP-mass spectrometry (MS) for earthworms and porewaters, while 235U:238U atom ratios were determined by multicollector (MC)-ICP-MS. Comparison of the porewater and earthworm isotopic values with those of the soil solids indicated that DU released into the environment during weapons test-firing operations was more labile and more bioavailable than naturally occurring U in the soils at the testing range. Importantly, DU was shown to be present in soil porewater even at a distance of approximately 185 m from the test-firing position and, along the extent of the transect was apparently associated with organic colloids.
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Affiliation(s)
- Ian W Oliver
- Scottish Universities Environmental Research Centre, Rankine Avenue, Scottish Enterprise Technology Park, East Kilbride, UK.
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