A hydrogeochemical and stable isotope study (H and O) was carried out in the Cuvelai-Etosha Basin in order to characterize available groundwater and to identify possible recharge mechanisms for the perched aquifers. Data were collected during seven field campaigns between 2013 and 2015 from a total of 24 shallow and deep groundwater hand-dug wells. In the investigated groundwaters, hydrogencarbonate is the dominating anion in both well types, whereas cations vary between calcium and magnesium in deep wells, and sodium and potassium in shallow wells. Groundwater chemistry is controlled by dissolution of carbonate minerals, silicate weathering and ion exchange. Stable isotopic composition suggests that deep groundwater is recharged by high-intensity/large rainfall events, whereas the shallow wells can even be recharged by less-intense/small rainfall events. Water in deep wells reflect a mixture of water influenced by evaporation during or before infiltration and water that infiltrated through fast preferential pathways, whereas shallow wells are strongly influenced by evaporation. The findings of this research contribute to improve the understanding of hydrogeochemistry, recharge paths and temporal variations of perched aquifers.
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http://dx.doi.org/10.1080/10256016.2016.1273913 | DOI Listing |
Sci Total Environ
December 2024
California Water Program, The Nature Conservancy, Sacramento, CA, USA; Rohde Environmental Consulting, LLC, Seattle, WA, USA; SUNY College of Environmental Science and Forestry, Syracuse, NY, USA.
RSC Adv
October 2024
Department of Environmental Science and Engineering, College of Architecture and Environment, Sichuan University No. 24 South Section 1, Yihuan Road Chengdu 610065 PR China
Convection and diffusion are key pathways for the migration of total petroleum hydrocarbons (TPH) and heavy metals (HMs) from soil to groundwater. However, the extent of their influence on pollutant migration, as well as the nonlinear relationships between these processes and pollutants, remains unclear. This study investigates the spatial distribution of TPH and HMs at a petrochemical site with complex hydrogeological conditions in southwestern China.
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November 2024
Chemistry Centre of Vila Real - CQVR, University of Trás-os-Montes and Alto Douro (UTAD), Ap. 1013, 5001-801 Vila Real, Portugal. Electronic address:
The B1 tailings dam of Córrego do Feijão iron-ore mine owned by Vale, S.A. company collapsed in 25 January 2019 releasing to the Ferro-Carvão stream watershed (32.
View Article and Find Full Text PDFChemosphere
November 2023
Key Laboratory of Geotechnical & Underground Engineering of Ministry of Education and Department of Geotechnical Engineering, Tongji University, Shanghai, 200092, PR China.
Soil and groundwater Cr(VI) pollution resulting from improper disposal and accidental spills is a critical problem worldwide. In this study, a comprehensive study was conducted to assess the hydrogeological conditions of a contaminated site, obtain spatiotemporal distribution and trend forecasts of pollutant Cr(VI), and determine the feasibility of applying clayey engineered barriers for pollution control. The results showed that the hydraulic conductivity (K) of the clayey barrier (1.
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October 2023
Geological and Mining Institute of Spain (IGME-CSIC), Spanish National Research Council, C/Ríos Rosas 23, 28003 Madrid. Spain. Electronic address:
Contaminated groundwater is a serious problem in developed countries. The abandonment of industrial waste may lead to acid drainage affecting groundwater and severely impacting the environment and urban infrastructure. We examined the hydrogeology and hydrochemistry of an urban area in Almozara (Zaragoza, Spain); built over an old industrial zone, with pyrite roasting waste deposits, there were acid drainage problems in underground car parks.
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