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... The ongoing contamination of groundwater with per- and polyfluoroalkyl substances (PFAS) has resulted in a global and rapidly growing interest in PFAS groundwater remediation. Preferred technologies that lead to PFAS destruction are often limited by not addressing all PFAS, being energy-intensive or not being suited for in-situ application. We developed nNiFe-activated carbon (AC) nanocomposites a ...
groundwater, etc ; Bacillus (bacteria); arsenic; genes; oxidoreductases; prokaryotic cells; China; Show all 7 Subjects
Abstract:
... Many investigations suggest that dissimilatory arsenate-respiring prokaryotes (DARPs) play a key role in stimulating reductive mobilization of As from solid phase into groundwater, but it is not clear how environmental Mn(II) affects the DARPs-mediated reductive mobilization of arsenic. To resolve this issue, we collected soil samples from a realgar tailings-affected area. We found that there were ...
... Polycyclic aromatic hydrocarbons (PAHs) and their oxygenated derivates (O-PAHs) are identified in soils and groundwater of industrialized sites and contribute to the risk for Humans and the Environment. Nevertheless, data are scarce in literature concerning their retention and transfer in soils and no soil - water partition coefficients are available for these compounds. Sorption of two PAHs, fluo ...
... Organophosphates (OPs) are an integral part of modern agriculture; however, due to overexploitation, OPs pesticides residues are leaching and accumulating in the soil, and groundwater contaminated terrestrial and aquatic food webs. Acute exposure to OPs could produce toxicity in insects, plants, animals, and humans. OPs are known for covalent inhibition of acetylcholinesterase enzyme in pests and ...
groundwater; groundwater treatment, etc ; models; permeability; Show all 4 Subjects
Abstract:
... A model of contaminant transport determined by infiltrating groundwater in geologic medium with adsorbing barrier is proposed, in which it is shown that requirements to the barrier permeability make a restriction on its adsorbing properties. Basing on the solution for contaminant concentration a restriction on minimal barrier’s length needed for treatment of contaminated region and characteristic ...
groundwater; groundwater contamination, etc ; geostatistics; hydraulic conductivity; Show all 4 Subjects
Abstract:
... Joint estimation of groundwater contaminant source characteristics and hydraulic conductivity is of great significance for contaminant transport models in heterogeneous subsurface media. As for accurate characterization of hydraulic conductivities, both geostatistical modeling and groundwater inverse modeling are alternative approaches. In this study, an iterative ensemble smoother and sequential ...
groundwater; groundwater flow, etc ; Bayesian theory; uncertainty; Show all 4 Subjects
Abstract:
... We present a novel approach to adaptive optimal design of groundwater surveys – a methodology for choosing the location of the next monitoring well. Our dual-weighted approach borrows ideas from Bayesian Optimisation and goal-oriented error estimation to propose the next monitoring well, given that some data is already available from existing wells. Our method is distinct from other optimal design ...
groundwater; groundwater contamination; groundwater flow, etc ; computer software; finite element analysis; models; risk; Show all 7 Subjects
Abstract:
... The Horizontal Reactive Media Treatment (HRX) well is a novel technology for in situ treatment of contaminated groundwater. The most significant technical performance risk associated with field-scale implementation of the HRX well is the potential for water to bypass the well untreated. Therefore, the groundwater capture simulation plays a very important role in the design of the HRX well. We buil ...
groundwater; groundwater contamination; groundwater extraction, etc ; adsorption; aquifers; arsenic; cost effectiveness; groundwater flow; iron; iron oxides; longevity; models; remediation; sand; Show all 14 Subjects
Abstract:
... Arsenic contamination of groundwater occurs due to both geogenic and anthropogenic processes. Conventional arsenic remediation techniques require extraction of groundwater into pump-and-treat systems, which are expensive and require long operational times. Hence, there is a need for cost-effective remediation. In this study, we assessed and validated the in situ remediation of arsenic contaminatio ...
groundwater; groundwater extraction, etc ; drawdown; models; rain; Taiwan; Show all 6 Subjects
Abstract:
... The equilibrium of natural groundwater systems can be disrupted by excessive withdrawal. Accurate estimation of groundwater levels is needed to assess water-level fluctuations caused by groundwater withdrawal and seasonal distributions of precipitation. This study aims to estimate the next-month’s groundwater levels using monthly real-world data that includes rainfall, electricity-estimated pumpin ...
groundwater; groundwater flow; groundwater recharge, etc ; aquifers; glaciers; ice; mountains; snowmelt; Alberta; Rocky Mountain region; Show all 10 Subjects
Abstract:
... The prevailing concern in the Western Canadian Plains is that glaciers from the eastern Canadian Rocky Mountains (CRM) are losing mass, thus affecting groundwater recharge in the Plains. The generally accepted hypothesis is that those glaciers are the geological source of groundwater for aquifers located in the Plains. The aquifers located in this region, close to the eastern part of the Rockies, ...
groundwater; groundwater extraction, etc ; food security; freshwater; sustainable development; Show all 5 Subjects
Abstract:
... Groundwater, the world's largest freshwater resource, is critically important for global food security. Excessive groundwater extraction has led to issues such as groundwater sustainability, scarcity, and stress; various indices have been developed for assessing them. The selection of the right index for the assessment is very important. Therefore, the existing index-based groundwater scarcity str ...
groundwater; groundwater flow, etc ; freshwater; humans; spring; springs (water); Show all 6 Subjects
Abstract:
... Springs sustain groundwater-dependent ecosystems and provide freshwater for human use. Springs often occur because faults modify groundwater flow pathways leading to discharge from aquifers with sufficiently high pressure. This study reviews the key characteristics and physical processes, field investigation techniques, modelling approaches and management strategies for fault-controlled spring sys ...
groundwater; groundwater flow, etc ; air; equations; pollutants; river flow; Show all 6 Subjects
Abstract:
... The present work derives analytical solutions of advection–dispersion equation (ADE) with temporal coefficients, and a pollutant’s point source moving linearly along the axis of a one-dimensional semi-infinite domain. The source is considered a varying and a uniform pulse source, respectively. The dispersion of pollutant originating from a varying pulse source may be supposed to occur along ground ...
groundwater; groundwater contamination, etc ; arsenic; ceramics; environmental management; oxidation; Show all 6 Subjects
Abstract:
... Iron (Fe) amended dual unit ceramic filters (DUCF) can be a viable treatment option for arsenic (As) removal from highly contaminated groundwater. The present field study investigated the effect of filter configurations, the separate-unit dual filter (SUDF) and connect-unit dual filter (CUDF), on As removal from groundwater having As concentration of 475 μg/L. SUDF was configured by placing 1st an ...
... Pahute Mesa (Nevada, USA) was the site of 85 underground nuclear tests between 1965 and 1992 whose residual radiochemical inventory poses a contaminant threat to local groundwater resources. To assess the fate and transport of these radionuclides in groundwater, several geochemical studies, including this one, have been conducted to understand long-term groundwater flow patterns at, and downgradie ...
groundwater; groundwater flow, etc ; aquifers; finite element analysis; prediction; Show all 5 Subjects
Abstract:
... Numerical simulations of groundwater flow are used to analyze and predict the response of an aquifer system to its change in state by approximating the solution of the fundamental groundwater physical equations. The most used and classical methodologies, such as Finite Difference (FD) and Finite Element (FE) Methods, use iterative solvers which are associated with high computational cost. This stu ...
groundwater; groundwater extraction; groundwater flow, etc ; basins; confined aquifer; industry; sustainable development; water management; water supply; Indonesia; Show all 10 Subjects
Abstract:
... The escalating community demands for water supply in urban areas lead to overexploitation on groundwater and worsening the condition of the resources. These exploitation activities will affect the quality, quantity, and continuity (QQC) of groundwater, especially those that are produced as the resource for the water supply industry. The study area is a water supply industry plant located in Bekasi ...
groundwater; groundwater flow; groundwater recharge, etc ; aquifers; hydrochemistry; models; soil water balance; subsidence; water management; water supply; Show all 10 Subjects
Abstract:
... In the Grünstadt area the water supply is realised by mostly local pumping wells in the Bunter aquifer system. The Bunter has a spatially complex structure due to the geological-tectonic setting. In combination with estimations to the groundwater flow direction and groundwater age, the area can be split into balanceable sub-areas.Data of groundwater levels and hydrochemistry indicate significant c ...
groundwater; groundwater recharge, etc ; alluvium; basins; freshwater; highlands; lithology; Kenya; Show all 8 Subjects
Abstract:
... The demand for freshwater has continuously increased in the arid areas of Ewaso Ng'iro – Lagh Dera basin, Kenya. This study aimed to and mapped areas of potential groundwater recharge in the basin by integrating factors that influence groundwater recharge using Analytical Hierarchical Process, and Fuzzy-Analytical Hierarchical Process in ArcGIS. The results of this study are presented in form of m ...