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Regional groundwater modeling of the guarani aquifer system
(2020-09-01)
The Guarani Aquifer System (GAS) is a strategic transboundary aquifer system shared by Brazil, Argentina, Paraguay and Uruguay. This article presents a groundwater flow model to assess the GAS system in terms of regional ...
The mechanism of 234U 238U activity ratio enhancement in karstic limestone groundwater
(Elsevier B.V., 1993-01-05)
Experimental etch/leach of Carboniferous Limestone gravels on a laboratory time-scale has demonstrated that 234U 238U activity ratios (AR's) greater than the radiochemical equilibrium value may be generated on short ...
Nitrates in groundwater of the state of São PauloNitrato em águas subterrâneas do estado de São Paulo
(2019-01-01)
As groundwater consumption increases, its quality and consequently its potability are proportionally affected. Nitrates stand out among the agents that contribute to the loss of groundwater potability, as they are the most ...
Recharge seasonality based on stable isotopes: Nongrowing season bias altered by irrigation in Nebraska
(2020-03-30)
The sustainability of groundwater resources for agricultural and domestic use is dependent on both the groundwater recharge rate and the groundwater quality. The main purpose of this study was to improve the understanding ...
Effect of the Irrigation Canal Network on Surface and Groundwater Interactions in the Lower Valley of the Cachapoal River, Chile
(Instituto de Investigaciones Agropecuarias, INIA, 2009)
Nitrate-dependent Uranium mobilisation in groundwater
(2019-11-25)
Nitrate is a critical substance that determines the prevailing redox conditions in groundwater, and in turn the behaviour of Uranium (U). Therefore, the excessive use of nitrate-fertiliser in agricultural catchments could ...
Fluoride prevalence in groundwater around a fluorite mining area in the flood plain of the River Swat, Pakistan
(2018-09-01)
This study investigated the fluoride (F−) concentrations and physicochemical parameters of the groundwater in a fluorite mining area of the flood plain region of the River Swat, with particular emphasis on the fate and ...
Hydrochemical and stable isotopes (H, O, S) signatures in deep groundwaters of Parana basin, Brazil
(Springer, 2015-01-01)
This paper describes a hydrochemical (major and trace elements) and stable isotopes (H, O, S) study of rainwater and groundwater in a Guarani Aquifer System (GAS) transect at Sao Paulo State, Brazil. The Brazilian Code of ...
The dissolved uranium concentration and 234U/238U activity ratio in groundwaters from spas of southeastern Brazil
(2017-01-01)
This paper describes the natural radioactivity due to 238U and 234U in 75 water sources from spas located in 14 municipalities in São Paulo and Minas Gerais states, Brazil. These waters are extensively utilized for drinking ...