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Author Dutova, E.M.; Nikitenkov, A.N.; Pokrovskiy, V.D.; Banks, D.; Frengstad, B.S.; Parnachev, V.P. url  openurl
  Title Modelling of the dissolution and reprecipitation of uranium under oxidising conditions in the zone of shallow groundwater circulation Type Journal Article
  Year 2017 Publication Journal of Environmental Radioactivity Abbreviated Journal  
  Volume 178-179 Issue Pages 63-76  
  Keywords Groundwater, Hydrochemical modelling, Mineralisation, Natural uranium, Ore, Solubility  
  Abstract (down) Generic hydrochemical modelling of a grantoid-groundwater system, using the Russian software “HydroGeo”, has been carried out with an emphasis on simulating the accumulation of uranium in the aqueous phase. The baseline model run simulates shallow granitoid aquifers (U content 5 ppm) under conditions broadly representative of southern Norway and southwestern Siberia: i.e. temperature 10 °C, equilibrated with a soil gas partial CO2 pressure (PCO2, open system) of 10−2.5 atm. and a mildly oxidising redox environment (Eh = +50 mV). Modelling indicates that aqueous uranium accumulates in parallel with total dissolved solids (or groundwater mineralisation M – regarded as an indicator of degree of hydrochemical evolution), accumulating most rapidly when M = 550–1000 mg L−1. Accumulation slows at the onset of saturation and precipitation of secondary uranium minerals at M = c. 1000 mg L−1 (which, under baseline modelling conditions, also corresponds approximately to calcite saturation and transition to Na-HCO3 hydrofacies). The secondary minerals are typically “black” uranium oxides of mixed oxidation state (e.g. U3O7 and U4O9). For rock U content of 5–50 ppm, it is possible to generate a wide variety of aqueous uranium concentrations, up to a maximum of just over 1 mg L−1, but with typical concentrations of up to 10 μg L−1 for modest degrees of hydrochemical maturity (as indicated by M). These observations correspond extremely well with real groundwater analyses from the Altai-Sayan region of Russia and Norwegian crystalline bedrock aquifers. The timing (with respect to M) and degree of aqueous uranium accumulation are also sensitive to Eh (greater mobilisation at higher Eh), uranium content of rocks (aqueous concentration increases as rock content increases) and PCO2 (low PCO2 favours higher pH, rapid accumulation of aqueous U and earlier saturation with respect to uranium minerals).  
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  Series Volume Series Issue Edition  
  ISSN 0265-931x ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ dutova_modelling_2017 Serial 114  
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Author Ruiz, O.; Thomson, B.; Cerrato, J.M.; Rodriguez-Freire, L. url  openurl
  Title Groundwater restoration following in-situ recovery (ISR) mining of uranium Type Journal Article
  Year 2019 Publication Applied Geochemistry Abbreviated Journal  
  Volume 109 Issue Pages 104418  
  Keywords Aquifer stabilization, Ground water restoration, In-situ leach mining, In-situ recovery, Uranium  
  Abstract (down) From 1950 through the early 1980’s New Mexico accounted for roughly half of domestic uranium (U) production for the nuclear power industry and the nation’s weapon programs. Increased interest in nuclear energy has led to proposals for renewed development using both underground mining and uranium in situ recovery (ISR). When feasible, ISR greatly reduces waste generated by the mining and milling processes, however, the ability to restore ground water to acceptable quality after ISR ends is uncertain. This research investigated two methods of stabilizing an aquifer following ISR. Batch and column studies were performed to evaluate chemical and biological methods of stabilization. Columns packed with ore were first leached with an aerated NaHCO3 ground water solution to simulate ISR. Constituents present at elevated concentrations after leaching included molybdenum (Mo), selenium (Se), U, and vanadium (V). Chemical stabilization was studied by passing a phosphate (PO43-) amended solution through the ore to achieve passivation of mineral surfaces by P precipitates. Microbial stabilization was studied by passing a lactate solution through the ore to stimulate growth of anaerobic metal- and sulfate-reducing organisms to reduce U and other elements to less soluble phases. Analyses of the solids from the columns after completion of these experiments by X-ray photo electron spectroscopy (XPS) identified phosphate on samples near the column inlet of the chemically stabilized columns. Microbial populations were characterized by Illumina DNA sequencing and confirmed the presence of metal- and sulfate-reducing organisms. Neither chemical nor microbial stabilization method achieved contaminant immobilization, which is believed due to limited mixing of the stabilization solutions with the contaminated leach solutions. These results emphasize that ground water hydrodynamics, especially mixing, must be considered in aquifer restoration of soluble constituents.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0883-2927 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ ruiz_groundwater_2019 Serial 153  
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Author Tariq, A.; Beni, L.H.; Ali, S.; Adnan, S.; Hatamleh, W.A. url  openurl
  Title An effective geospatial-based flash flood susceptibility assessment with hydrogeomorphic responses on groundwater recharge Type Journal Article
  Year 2023 Publication Groundwater for Sustainable Development Abbreviated Journal  
  Volume 23 Issue Pages 100998  
  Keywords Flood hydrology, AHP, Flood susceptibility, FR, Unit stream power, GIS  
  Abstract (down) Floods are one of the most common natural disasters, resulting in the extensive destruction of infrastructure, property, and human life. The destructive potential of a flood depends on numerous factors, including the size of the flood, the rate of flooding, the time it takes for the water to move through a given area, the river’s planform and cross-section geometry, and other similar factors. The present study is a unique analysis of flood mapping that was accomplished with the help of the Analytical Hierarchy Process (AHP), Frequency Ratio (FR), and hydrogeomorphic response to floods by integrating geospatial analysis and unit stream power modeling. The Indus catchment region of Pakistan is where the subject topic is put into practice. According to the hydrologic analysis of the yearly peak discharge, the hydro-station in Gilgit-Baltistan can move boulders measuring up to 0.5 m in height during significant flooding. On the other hand, there will be no change to the geometry of the cross-section throughout 1980–2020 in Gilgit-Baltistan. The flood susceptibility map is constructed using data from twelve influencing parameters, including elevation, proximity to the drainage network, slope, drainage density, geomorphology, rainfall, the curvature of the topography, flow accumulation, geology, land use, Topographic Wetness Index (TWI), and Stream Power Index (SPI). The area under the curve (AUC) approach, which demonstrates a substantial degree of accuracy (85% and 83%), is utilized to evaluate the effectiveness of the AHP and FR. The current study fills the gaps between the geospatial approach and the hydrogeomorphic assessment of flood to determine flood susceptibility.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2352-801x ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Tariq2023100998 Serial 234  
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Author Mühr-Ebert, E.L.; Wagner, F.; Walther, C. url  openurl
  Title Speciation of uranium: Compilation of a thermodynamic database and its experimental evaluation using different analytical techniques Type Journal Article
  Year 2019 Publication Applied Geochemistry Abbreviated Journal  
  Volume 100 Issue Pages 213-222  
  Keywords  
  Abstract (down) Environmental hazards are caused by uranium mining legacies and enhanced radioactivity in utilized groundwater and surface water resources. Knowledge of uranium speciation in these waters is essential for predicting radionuclide migration and for installing effective water purification technology. The validity of the thermodynamic data for the environmental media affected by uranium mining legacies is of utmost importance. Therefore, a comprehensive and consistent database was established according to current knowledge. The uranium data included in the database is based on the NEA TDB (Guillaumont et al., 2003) and is modified or supplemented as necessary e.g. for calcium and magnesium uranyl carbonates. The specific ion interaction theory (Brönsted, 1922) is used to estimate activity constants, which is sufficient for the considered low ionic strengths. The success of this approach was evaluated by comparative experimental investigations and model calculations (PHREEQC (Parkhurst and Appelo, 1999)) for several model systems. The waters differ in pH (2.7–9.8), uranium concentration (10−9-10−4 mol/L) and ionic strength (0.002–0.2 mol/L). We used chemical extraction experiments, ESI-Orbitrap-MS and time-resolved laser-induced fluorescence spectroscopy (TRLFS) to measure the uranium speciation. The latter method is nonintrusive and therefore does not change the chemical composition of the investigated waters. This is very important, because any change of the system under study may also change the speciation.  
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  Series Volume Series Issue Edition  
  ISSN 0883-2927 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ muhr-ebert_speciation_2019 Serial 142  
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Author Martínez-Santos, P.; Martínez-Alfaro, P.E. url  openurl
  Title A priori mapping of historical water-supply galleries based on archive records and sparse material remains. An application to the Amaniel qanat (Madrid, Spain) Type Journal Article
  Year 2014 Publication Journal of Cultural Heritage Abbreviated Journal  
  Volume 15 Issue 6 Pages 656-664  
  Keywords Hydraulic heritage, Qanat, Groundwater, Foggara, Water-supply, Amaniel, Madrid  
  Abstract (down) Engineering heritage refers to a broad variety of items of social, economic, aesthetic or historic relevance, including roads, dams, buildings and supply networks. Due to their utilitarian nature, their heritage value is often overlooked. This occurs even with those infrastructures that have played an essential role in underpinning the daily existence of entire civilizations. Underground water-supply networks provide an excellent example. Although there are exceptions, water networks tend to be functional in design, rather than monumental. Moreover, they present intricate linear layouts that often span several kilometres. This means they are costly to maintain once their operational life is over, and that they are prone to abandonment and destruction. Devising a priori protection strategies is important to preserve these valuable cultural assets. The following pages present a method to map linear structures based on archive records and sparse material remains. The method is illustrated through its application to the Amaniel qanat, a water-supply gallery built in Madrid, Spain, in the early 17th Century. An appraisal of the known remains was carried out first, leading to an inventory of galleries, shafts, shaft caps and deposits. This was followed by a thorough survey of over one thousand handwritten manuscripts, including physical descriptions of the aqueduct, budget accounts or water metering campaigns, among other documents. Known remains and written evidence were matched against original and auxiliary maps to reconstruct the itinerary of the aqueduct. This led to the identification of sectors where it is still possible to find remains in good condition. Thus, a priori mapping is advocated a valuable technique to locate and preserve these remains, as well as to devise non-invasive surveys and establish heritage protection zones.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1296-2074 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Martinezsantos2014656 Serial 270  
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Author Heaton, T.H.E. url  openurl
  Title Sources of the nitrate in phreatic groundwater in the western Kalahari Type Journal Article
  Year 1984 Publication Journal of Hydrology Abbreviated Journal  
  Volume 67 Issue 1 Pages 249-259  
  Keywords  
  Abstract (down) Elevated levels of nitrate occur in phreatic groundwater in the western Kalahari, Namibia. Nitrate in water containing 0.4–3.1 meq NO−3l−1, of widespread occurrence, has δ15N values in the range +4.9 to +8.0‰, suggesting natural derivation from the soil. The sporadic occurrence of very high levels of nitrate (> 4 meq NO−3l−1), which has δ15N between +9.3 to +18.7‰, reflects pollution derived from animal waste. The importance of considering the possible isotopic effects of denitrification, and the significance of leaching in the nitrogen budget of the Kalahari soil, are also discussed.  
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  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-1694 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Heaton1984249 Serial 278  
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Author Stone, A.E.C.; Edmunds, W.M. url  openurl
  Title Naturally-high nitrate in unsaturated zone sand dunes above the Stampriet Basin, Namibia Type Journal Article
  Year 2014 Publication Journal of Arid Environments Abbreviated Journal  
  Volume 105 Issue Pages 41-51  
  Keywords Kalahari, Namibia, Nitrate in the unsaturated zone, Stampriet Basin, Transboundary basin, Unsaturated zone recharge  
  Abstract (down) Elevated groundwater nitrate levels are common in drylands, often in excess of WHO guidelines, with concern for human and animal health. In light of recent attempts to identify nitrate sources in the Kalahari this paper presents the first unsaturated zone (USZ) nitrate profiles and recharge rate estimates for the important transboundary Stampriet Basin, alongside the first rainfall chemistry records. Elevated subsurface nitrate reaches 100–250 and 250–525 mg/L NO3–N, with NO3–N/Cl of 4–12, indicating input above evapotranspiration. Chloride mass balance recharge rates range from 4 to 27 mm/y, indicating a vertical movement of these nitrate pulses toward the water table over multi-decadal timescales. These profiles are sampled from dune crests, away from high concentrations of animals and without termite mounds. Given low-density animal grazing is unlikely to contribute consistent spot-scale nitrate over decades, these profiles give an initial estimate of naturally-produced concentrations. This insight is important for the management of the Stampriet Basin and wider Kalahari groundwater. This study expands our knowledge about elevated nitrate in dryland USZs, demonstrating that it can occur as pulses, probably in response to transient vegetation cover and that it is not limited to long-residence time USZs with very limited downward moisture flux (recharge).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0140-1963 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Stone201441 Serial 218  
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Author Stone, A.E.C.; Edmunds, W.M. url  openurl
  Title Naturally-high nitrate in unsaturated zone sand dunes above the Stampriet Basin, Namibia Type Journal Article
  Year 2014 Publication Journal of Arid Environments Abbreviated Journal  
  Volume 105 Issue Pages 41-51  
  Keywords Kalahari, Namibia, Nitrate in the unsaturated zone, Stampriet Basin, Transboundary basin, Unsaturated zone recharge  
  Abstract (down) Elevated groundwater nitrate levels are common in drylands, often in excess of WHO guidelines, with concern for human and animal health. In light of recent attempts to identify nitrate sources in the Kalahari this paper presents the first unsaturated zone (USZ) nitrate profiles and recharge rate estimates for the important transboundary Stampriet Basin, alongside the first rainfall chemistry records. Elevated subsurface nitrate reaches 100–250 and 250–525 mg/L NO3–N, with NO3–N/Cl of 4–12, indicating input above evapotranspiration. Chloride mass balance recharge rates range from 4 to 27 mm/y, indicating a vertical movement of these nitrate pulses toward the water table over multi-decadal timescales. These profiles are sampled from dune crests, away from high concentrations of animals and without termite mounds. Given low-density animal grazing is unlikely to contribute consistent spot-scale nitrate over decades, these profiles give an initial estimate of naturally-produced concentrations. This insight is important for the management of the Stampriet Basin and wider Kalahari groundwater. This study expands our knowledge about elevated nitrate in dryland USZs, demonstrating that it can occur as pulses, probably in response to transient vegetation cover and that it is not limited to long-residence time USZs with very limited downward moisture flux (recharge).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0140-1963 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Stone201441 Serial 279  
Permanent link to this record
 

 
Author Stone, A.E.C.; Edmunds, W.M. url  openurl
  Title Naturally-high nitrate in unsaturated zone sand dunes above the Stampriet Basin, Namibia Type Journal Article
  Year 2014 Publication Journal of Arid Environments Abbreviated Journal  
  Volume 105 Issue Pages 41-51  
  Keywords Kalahari, Namibia, Nitrate in the unsaturated zone, Stampriet Basin, Transboundary basin, Unsaturated zone recharge  
  Abstract (down) Elevated groundwater nitrate levels are common in drylands, often in excess of WHO guidelines, with concern for human and animal health. In light of recent attempts to identify nitrate sources in the Kalahari this paper presents the first unsaturated zone (USZ) nitrate profiles and recharge rate estimates for the important transboundary Stampriet Basin, alongside the first rainfall chemistry records. Elevated subsurface nitrate reaches 100–250 and 250–525 mg/L NO3–N, with NO3–N/Cl of 4–12, indicating input above evapotranspiration. Chloride mass balance recharge rates range from 4 to 27 mm/y, indicating a vertical movement of these nitrate pulses toward the water table over multi-decadal timescales. These profiles are sampled from dune crests, away from high concentrations of animals and without termite mounds. Given low-density animal grazing is unlikely to contribute consistent spot-scale nitrate over decades, these profiles give an initial estimate of naturally-produced concentrations. This insight is important for the management of the Stampriet Basin and wider Kalahari groundwater. This study expands our knowledge about elevated nitrate in dryland USZs, demonstrating that it can occur as pulses, probably in response to transient vegetation cover and that it is not limited to long-residence time USZs with very limited downward moisture flux (recharge).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0140-1963 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ stone_naturally-high_2014 Serial 91  
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Author Pree, T.A.D. url  openurl
  Title The politics of baselining in the Grants uranium mining district of northwestern New Mexico Type Journal Article
  Year 2020 Publication Journal of Environmental Management Abbreviated Journal  
  Volume 268 Issue Pages 110601  
  Keywords Critical stakeholder analysis, Environmental cleanup, Environmental monitoring, Mining reclamation/remediation/restoration, Politics of baselining  
  Abstract (down) During the second half of the twentieth century, northwestern New Mexico served as the primary production site for one of the world’s largest nuclear arsenals. From 1948 to 1970 the “Grants uranium district” provided almost half of the total uranium ore accumulated by the United States federal government for the production of nuclear weapons, in addition to becoming a national source for commercial nuclear energy from the late 1960s to the early 1990s. By the twenty-first century, after a prolonged period of economic decline that began in the late 1970s, all uranium mining and milling in New Mexico had ceased, leaving a legacy of environmental health impacts. What was once referred to as “The Uranium Capital of the World” now encompasses over a thousand abandoned uranium mines and seven massive uranium mill tailings piles, which are associated with airborne and soil contamination as well as groundwater plumes of uranium and other contaminants of concern, in a landscape that has been fractured by underground mine workings and punctured by thousands of exploratory boreholes. This article presents an ethnographic study of the diverse forms of expertise involved in monitoring and managing the mine waste and mill tailings. Drawing from over two years of ethnographic research, I describe the relationship between different stakeholders from local communities, government agencies, and transnational mining corporations as they deliberate about the possibility of cleaning up the former mining district. My thesis is that the possibility of cleaning up the Grants district hinges on the “politics of baselining”—a term I introduce to describe the relationship between stakeholders and their competing environmental models and hydrogeological theories; each accounts for a different geological past prior to mining that can be deemed “natural,” as the background against which to measure the anthropogenic impacts from mining.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0301-4797 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ pree_politics_2020 Serial 151  
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