Assessment of groundwater quality scenario in respect of fluoride and nitrate contamination in and around Gharbar village, Jharkhand, India

Abstract

Present study deals with the identification of geochemical processes and the probable mobilization mechanism responsible for the release of fluoride (F−) and nitrate (NO3−) in groundwater. For this purpose 50 groundwater samples are collected from the Gharbar and its adjacent villages of Jharkhand. The order of abundance of anion and cation in the groundwater sample are HCO3– > Cl− > SO42- > NO3− > F− > Br− and Ca2+ > Na+ > Mg2+ > K+ respectively. F− concentration ranges from 0.01 to 18.55 mg/L and the NO3− concentration ranges from 34.10 to 319.10 mg/L where majority of the water samples exceeds the permissible limit of F− (1.5 mg/L) and NO3− (45 mg/L). Alkaline aquifer condition accelerates the mobilization of F− in groundwater due to enhanced rate of weathering of fluoride-bearing minerals whereas anthropogenic activities play a major role in NO3− contamination of the study area. Saturation index (SI) indicates under-saturation of fluorite and calcite in the majority of water samples. Principal component analysis reveals 3 principal components explaining 72.33% of the data variance and indicates anthropogenic sources of contamination of NO3− and geogenic sources of contamination for F−. Keywords: Fluoride, Nitrate, Hydrogeochemistry, Weathering, Saturation index (SI), Gharbar village, Jharkhand