Chemical Evolution of Groundwater in the Dindefello Plain Area in South-Eastern Senegal

This study was to clarify the main mechanisms of shallow groundwater mineralization in the Dindefello Plain Area.Water composition data obtained in this study were subjected to aqueous speciation calculations together with data plotting on key diagrams so as to create work assumptions.Hypothesized reaction models of the processes of chemical weathering of carbonates and silicate minerals under the carbon dioxide regime were proposed and tested by selecting two water sample analyses interpreted as "starting" and "ending" water composition along a hydrologic flow line, and then running the PHREEQC (version 2) batch modeling procedure, to simulate chemical balances and compositional variations of groundwater within the geochemical system.For the flow path data discussed here, there was close agreement between the model results and the observed hydrochemistry, and so the proposed geochemical evolution model was deemed reliable.