24 research outputs found
Onderzoek naar de hydrogeologische en hydrochemische toestand van de Neogene Aquifer in Vlaanderen met behulp van modellering en isotopen hydrochemie
Methodologie, ontwikkeld in BRIDGE, voor de bepaling van drempelwaarden en natuurlijke achtergrondwaarden van grondwaterlichamen: toepassing op het Vlaamse CKS_0200_GWL_1 grondwaterlichaam
Application to CKS_0200_GWL_1 and compliance testing of the methodology developed in BRIDGE for the determination of threshold values and natural background levels for groundwater bodies
A new correction model for 14C ages in aquifers with complex geochemistry: application to the Neogene Aquifer, Belgium
Determination of Natural Background Levels (NBL) and Threshold Values (TV) for the CKS_0200_GWL_1 Groundwater Body in Flanders and Application to the Zoersel Forest Nature Reserve
Natural background concentrations of trace elements in aquifers of the Flemish Region, as a reference for the governmental sanitation policy
Hydrochemistry and source for high fluoride in groundwater of the Nairobi area, Kenya
This study aims to identify the hydrogeochemical processes influencing the high fluoride concentrations in groundwater of the Nairobi area, Kenya. For this purpose 16 groundwater samples were collected and analysed. Fluoride concentrations above the WHO standard are found in the downstream areas. The high F- concentrations are correlated with high sodium and pH and low Ca2+ concentrations. Weathering of sodium-rich alkaline igneous rocks causes a pH increase resulting in an increase in HCO3- and CO32- by dissolution of CO2. Groundwater becomes oversaturated compared to calcite and calcite precipitation occurs, leading to a decrease in Ca2+. This causes a sub-saturation with respect to fluorite and dissolution of fluorite increases the F- concentration. These reactions were modelled using the PHREEQC model and the results showed a good agreement with the measured groundwater quality, indicating that the proposed reactions are plausible for explaining the observed concentrations in groundwater