Vulnerability of intensively-exploited hard-rock aquifers to fluoride contamination in India: impact of global change

Hélène Pauwels (1) , Marie Pettenati (1) , Jérome Perrin (1) , Philippe Négrel (1)

1 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)

A geochemical study was conducted to obtain a comprehensive understanding of fluoride concentration increase in groundwater from a crystalline (hard-rock) aquifer in a small Indian agricultural watershed, where groundwater is intensively abstracted for paddy irrigation. A reactive1-D geochemical model using PHREEQC was used to reproduce fluoride concentrations under rice paddies taking into account evaporation and return flow related to paddies and water-rock interactions processes, namely dissolution of biotite, allanite and fluoro-apatite as well as absorption onto Al and Fe-hydroxides. This model can be applied to evaluate vulnerability to high fluoride concentration for several land use and climate change scenarios.

Domains: Geochemistry; Global Changes

Hélène Pauwels, Marie Pettenati, Jérome Perrin, Philippe Négrel. Vulnerability of intensively-exploited hard-rock aquifers to fluoride contamination in India: impact of global change. Fourth International Groundwater Conference (IGWC-2011), Sep 2011, Madurai, India. 6 p. ⟨hal-00608564⟩