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Author Lawrinenko, M.; Kurwadkar, S.; Wilkin, R.T. url  openurl
  Title Long-term performance evaluation of zero-valent iron amended permeable reactive barriers for groundwater remediation – A mechanistic approach Type Journal Article
  Year 2023 Publication Geoscience Frontiers Abbreviated Journal  
  Volume 14 Issue (down) 2 Pages 101494  
  Keywords Geochemistry, Iron, Permeable reactive barrier, Plating reactions, Reduction potential, Surface passivation  
  Abstract Permeable reactive barriers (PRBs) are used for groundwater remediation at contaminated sites worldwide. This technology has been efficient at appropriate sites for treating organic and inorganic contaminants using zero-valent iron (ZVI) as a reductant and as a reactive material. Continued development of the technology over the years suggests that a robust understanding of PRB performance and the mechanisms involved is still lacking. Conflicting information in the scientific literature downplays the critical role of ZVI corrosion in the remediation of various organic and inorganic pollutants. Additionally, there is a lack of information on how different mechanisms act in tandem to affect ZVI-groundwater systems through time. In this review paper, we describe the underlying mechanisms of PRB performance and remove isolated misconceptions. We discuss the primary mechanisms of ZVI transformation and aging in PRBs and the role of iron corrosion products. We review numerous sites to reinforce our understanding of the interactions between groundwater contaminants and ZVI and the authigenic minerals that form within PRBs. Our findings show that ZVI corrosion products and mineral precipitates play critical roles in the long-term performance of PRBs by influencing the reactivity of ZVI. Pore occlusion by mineral precipitates occurs at the influent side of PRBs and is enhanced by dissolved oxygen and groundwater rich in dissolved solids and high alkalinity, which negatively impacts hydraulic conductivity, allowing contaminants to potentially bypass the treatment zone. Further development of site characterization tools and models is needed to support effective PRB designs for groundwater remediation.  
  Address  
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  Series Volume Series Issue Edition  
  ISSN 1674-9871 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ lawrinenko_long-term_2023 Serial 143  
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Author Zeng, S.; Song, J.; Sun, B.; Wang, F.; Ye, W.; Shen, Y.; Li, H. url  openurl
  Title Seepage characteristics of the leaching solution during in situ leaching of uranium Type Journal Article
  Year 2023 Publication Nuclear Engineering and Technology Abbreviated Journal  
  Volume 55 Issue (down) 2 Pages 566-574  
  Keywords In situ leaching, Leaching solution viscosity, Seepage characteristics, Seepage pressure, Uranium-bearing sandstone  
  Abstract Investigating the seepage characteristics of the leaching solution in the ore-bearing layer during the in situ leaching process can be useful for designing the process parameters for the uranium mining well. We prepared leaching solutions of four different viscosities and conducted experiments using a self-developed multifunctional uranium ore seepage test device. The effects of different viscosities of leaching solutions on the seepage characteristics of uranium-bearing sandstones were examined using seepage mechanics, physicochemical seepage theory, and dissolution erosion mechanism. Results indicated that while the seepage characteristics of various viscosities of leaching solutions were the same in rock samples with similar internal pore architectures, there were regular differences between the saturated and the unsaturated stages. In addition, the time required for the specimen to reach saturation varied with the viscosity of the leaching solution. The higher the viscosity of the solution, the slower the seepage flow from the unsaturated stage to the saturated stage. Furthermore, during the saturation stage, the seepage pressure of a leaching solution with a high viscosity was greater than that of a leaching solution with a low viscosity. However, the permeability coefficient of the high viscosity leaching solution was less than that of a low viscosity leaching solution.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1738-5733 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ zeng_seepage_2023 Serial 211  
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Author Akter, A.; Tanim, A.H.; Islam, M.K. url  openurl
  Title Possibilities of urban flood reduction through distributed-scale rainwater harvesting Type Journal Article
  Year 2020 Publication Water Science and Engineering Abbreviated Journal  
  Volume 13 Issue (down) 2 Pages 95-105  
  Keywords Low-impact development (LID), SWMM, HEC-RAS, Remote sensing, Urban flooding, Inundation depth  
  Abstract Urban flooding in Chittagong City usually occurs during the monsoon season and a rainwater harvesting (RWH) system can be used as a remedial measure. This study examines the feasibility of rain barrel RWH system at a distributed scale within an urbanized area located in the northwestern part of Chittagong City that experiences flash flooding on a regular basis. For flood modeling, the storm water management model (SWMM) was employed with rain barrel low-impact development (LID) as a flood reduction measure. The Hydrologic Engineering Center’s River Analysis System (HEC-RAS) inundation model was coupled with SWMM to observe the detailed and spatial extent of flood reduction. Compared to SWMM simulated floods, the simulated inundation depth using remote sensing data and the HEC-RAS showed a reasonable match, i.e., the correlation coefficients were found to be 0.70 and 0.98, respectively. Finally, using LID, i.e., RWH, a reduction of 28.66% could be achieved for reducing flood extent. Moreover, the study showed that 10%–60% imperviousness of the subcatchment area can yield a monthly RWH potential of 0.04–0.45 m3 from a square meter of rooftop area. The model can be used for necessary decision making for flood reduction and to establish a distributed RWH system in the study area.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1674-2370 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Akter202095 Serial 247  
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Author Lightfoot, D.R. url  openurl
  Title Moroccan khettara: Traditional irrigation and progressive desiccation Type Journal Article
  Year 1996 Publication Geoforum Abbreviated Journal  
  Volume 27 Issue (down) 2 Pages 261-273  
  Keywords  
  Abstract A 300 km network of khettara (qanat) subsurface irrigation channels was excavated in the Tafilalt basin beginning in the late 14th century. More than 75 of these chains provided perennial water following the breakup of the ancient city of Sijilmassa. Khettara continued to function for much of the northern oasis until the early 1970s, when new technologies and government policies forced changes. Data on origins, maintenance, and current use were collected from archival sources, aerial photographs, Landsat imagery, and from interviews. Insufficient water resources and unsustainable practices have dramatically lowered the water table, drying up khettara. This has resulted in a loss of local control over water resources, abandonment of a sustainable irrigation system, and progressive desiccation.  
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  Series Volume Series Issue Edition  
  ISSN 0016-7185 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Lightfoot1996261 Serial 257  
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Author Ubierna, J.A.J. url  openurl
  Title Tunnel heritage in Spain: Roots of the underground Type Journal Article
  Year 1998 Publication Tunnelling and Underground Space Technology Abbreviated Journal  
  Volume 13 Issue (down) 2 Pages 131-141  
  Keywords  
  Abstract Spain has deep roots in the underground. The territory of myth and legend, of cave and tunnel, has existed in Spain since that ancient time overwhelmed with shreds of fog, where all was myth around heros like Túbal Hércules, Gárgoris and Abidis. The underground evokes strong links with life and death, light and darkness, and has served as a source of inspiration for art through the centuries. The history of tunnels in Spain reflects the mosaic of cultures that have inhabited Iberia from prehistoric times till today. This contribution on the subterranean History of Spain traces the country’s heritage in the form of natural caves, troglodyte dwellings, mining, crypts, galleries in fortresses and castles, aqueducts, qanats, cellars, and other landmarks.  
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  Series Volume Series Issue Edition  
  ISSN 0886-7798 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Ubierna1998131 Serial 260  
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Author Strandmann, P.A.E.P. von; Reynolds, B.C.; Porcelli, D.; James, R.H.; Calsteren, P. van; Baskaran, M.; Burton, K.W. url  openurl
  Title Assessing continental weathering rates and actinide transport in the Great Artesian Basin Type Journal Article
  Year 2006 Publication Geochimica et Cosmochimica Acta Abbreviated Journal  
  Volume 70 Issue (down) 18, Supplement Pages 497  
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  Series Volume Series Issue Edition  
  ISSN 0016-7037 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ strandmann_assessing_2006 Serial 116  
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Author Zeng, S.; Shen, Y.; Sun, B.; Zhang, N.; Zhang, S.; Feng, S. url  openurl
  Title Pore structure evolution characteristics of sandstone uranium ore during acid leaching Type Journal Article
  Year 2021 Publication Nuclear Engineering and Technology Abbreviated Journal  
  Volume 53 Issue (down) 12 Pages 4033-4041  
  Keywords Acid method, In situ leaching, Nuclear magnetic resonance, Pore characteristic, Sandstone uranium ore  
  Abstract To better understand the permeability of uranium sandstone, improve the leaching rate of uranium, and explore the change law of pore structure characteristics and blocking mechanism during leaching, we systematically analyzed the microstructure of acid-leaching uranium sandstone. We investigated the variable rules of pore structure characteristics based on nuclear magnetic resonance (NMR). The results showed the following: (1) The uranium concentration change followed the exponential law during uranium deposits acid leaching. After 24 h, the uranium leaching rate reached 50%. The uranium leaching slowed gradually over the next 4 days. (2) Combined with the regularity of porosity variation, Stages I and II included chemical plugging controlled by surface reaction. Stage I was the major completion phase of uranium displacement with saturation precipitation of calcium sulfate. Stage II mainly precipitated iron (III) oxide-hydroxide and aluminum hydroxide. Stage III involved physical clogging controlled by diffusion. (3) In the three stages of leaching, the permeability of the leaching solution changed with the pore structure, which first decreased, then increased, and then decreased.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1738-5733 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ zeng_pore_2021 Serial 199  
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Author Schwiede, M.; Duijnisveld, W.H.M.; Böttcher, J. url  openurl
  Title Investigation of processes leading to nitrate enrichment in soils in the Kalahari Region, Botswana Type Journal Article
  Year 2005 Publication Physics and Chemistry of the Earth, Parts A/B/C Abbreviated Journal  
  Volume 30 Issue (down) 11 Pages 712-716  
  Keywords Nitrate, Arenosol soils, Semi-arid, Kalahari, Cattle, Chloride, Travel time  
  Abstract In Southern Africa elevated nitrate concentrations are observed in mostly uninhabited semi-arid areas. In the Kalahari of Botswana groundwater locally exhibits concentrations up to 600mg/l. It is assumed, that nitrate found in the groundwater originates mainly from nitrogen input and transformations in the soils. Our investigations in the Kalahari between Serowe and Orapa show that cattle raising is an important source for enhanced nitrate concentrations in the soils (Arenosols). But also in termite mounds very high nitrate stocks were found, and under natural vegetation (acacia trees and shrubs) nitrate concentrations were mostly unexpectedly high. This nitrate enrichment in the soils poses a serious threat to the groundwater quality. However, calculated soil water age distributions in the unsaturated zone clearly show that today’s nitrate pollution of the groundwater below the investigation area could originate from natural sources, but cannot be caused by the current land use for cattle raising.  
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  Series Volume Series Issue Edition  
  ISSN 1474-7065 ISBN Medium  
  Area Expedition Conference  
  Notes Integrated Water Resources Management (IWRM) and the Millennium Development Goals: Managing Water for Peace and Prosperity Approved no  
  Call Number THL @ christoph.kuells @ Schwiede2005712 Serial 276  
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Author Zhao, Y.; Li, X.; Lei, L.; Chen, L.; Luo, Z. url  openurl
  Title Permeability evolution mechanism and the optimum permeability determination of uranium leaching from low-permeability sandstone treated with low-frequency vibration Type Journal Article
  Year 2023 Publication Journal of Rock Mechanics and Geotechnical Engineering Abbreviated Journal  
  Volume 15 Issue (down) 10 Pages 2597-2610  
  Keywords Chemical reactive rate, Low-frequency vibration, Low-permeability sandstone, Optimum permeability, Permeability evolution mechanism, Uranium migration  
  Abstract Low-frequency vibrations can effectively improve natural sandstone permeability, and higher vibration frequency is associated with larger permeability. However, the optimum permeability and permeability evolution mechanism for uranium leaching and the relationship between permeability and the change of chemical reactive rate affecting uranium leaching have not been determined. To solve the above problems, in this study, identical homogeneous sandstone samples were selected to simulate low-permeability sandstone; a permeability evolution model considering the combined action of vibration stress, pore water pressure, water flow impact force, and chemical erosion was established; and vibration leaching experiments were performed to test the model accuracy. Both the permeability and chemical reactions were found to simultaneously restrict U6+ leaching, and the vibration treatment increased the permeability, causing the U6+ leaching reaction to no longer be diffusion-constrained but to be primarily controlled by the reaction rate. Changes of the model calculation parameters were further analyzed to determine the permeability evolution mechanism under the influence of vibration and chemical erosion, to prove the correctness of the mechanism according to the experimental results, and to develop a new method for determining the optimum permeability in uranium leaching. The uranium leaching was found to primarily follow a process consisting of (1) a permeability control stage, (2) achieving the optimum permeability, (3) a chemical reactive rate control stage, and (4) a channel flow stage. The resolution of these problems is of great significance for facilitating the application and promotion of low-frequency vibration in the CO2 + O2 leaching process.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1674-7755 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ zhao_permeability_2023 Serial 198  
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Author Severi, A.; Masoudian, M.; Kordi, E.; Roettcher, K. url  doi
openurl 
  Title Discharge coefficient of combined-free over-under flow on a cylindrical weir-gate Type Journal Article
  Year 2015 Publication ISH Journal of Hydraulic Engineering Abbreviated Journal  
  Volume 21 Issue (down) 1 Pages 42-52  
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  Address  
  Corporate Author Thesis  
  Publisher Taylor & Francis Place of Publication Editor  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ doi:10.1080/09715010.2014.939503 Serial 88  
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