Fluoride behaviour analysis in groundwater with reference to hydrogeochemical parameters in basaltic aquifers using remote sensing and GIS technique in parts of Burhner watershed, MP, India

Abstract

High fluoride concentration in groundwater leads to health threat to millions of people around the world; therefore, a systematic study is required to understand the behaviour of fluoride in water in terms of the local hydrogeological setting and other hydrogeochemical parameters. The present study is an attempt to assess the hydrogeology of groundwater in the study area to understand the fluoride behaviour in groundwater and to deduce the chemical parameters responsible for the dissolution activity of fluoride. F− value varies from 0.04 to 14.6 mg/l (mean: 3.15 mg/l) in the stuldy area. It is geologically occupied by basalt rocks where groundwater occurs in the weathered and fractured portions of the rocks and under semi-confined to confined conditions in fractured rocks. High F− concentration is observed in deeper aquifers compared to shallow aquifers. Physicochemical conditions like decomposition, dissociation and subsequent dissolution along with long residence time are responsible for leaching of F− into the groundwater. F− has +ve or −ve correlation with other parameters of water samples as per their nature. Simple to compound pahoehoe basaltic lava flows are responsible for the fluoride contamination in the confined aquifers (bore wells) of the study area. Overall confined aquifer water quality on the basis of fluoride concentration was found to be unsatisfactory for drinking purposes. About 57.13% of confined aquifers showed higher fluoride than the permissible limit but 100% unconfined aquifers (dug wells) have a low level of fluoride concentration, i.e. below the permissible limit.