Fluoride Action Network

Geochemical assessment of fluoride enrichment and nitrate contamination in groundwater in hard-rock aquifer by using graphical and statistical methods

Source: Journal of Earth System Science 127:104. | September 10th, 2018 | By Sunil Kumar Srivastsava and A L Ramanathan
Location: India

Abstract

This systematic study was carried out with objective to delineate the various sources responsible for NO?3 contamination and F enrichment by utilizing statistical and graphical methods. Since Central Ground Water Board, India, indicated susceptibility of NO3 contamination and F? enrichment, in most of the groundwater, NO3 and F concentration primarily observed >45 and >1.5 mg/L, respectively, i.e., higher than the permissible limit for drinking water. Water Quality Index (WQI) indicates ˜22.81% groundwater are good-water, ˜71.14% groundwater poor-water, ?5.37% very poor-water and 0.67% unsuitable for drinking purpose. Piper diagram indicates ˜59.73% groundwater hydrogeochemical facies are Ca–Mg–HCO3 water-types, ˜28.19% Ca–Mg–SO4–Cl water-types, ˜8.72% Na–K–SO4–Cl water-types and 3.36% Na–K–HCO3 water-types. This classification indicates dissolution and mixing are mainly controlling groundwater chemistry. Salinity diagram indicate ˜44.30% groundwater under in low sodium and medium salinity hazard, ˜49.66% groundwater fall under low sodium and high salinity hazard, ˜3.36% groundwater fall under very-high salinity hazard. Sodium adsorption ratio indicates ˜97% groundwater are in excellent condition for irrigation. The spatial distribution of NO3 indicates significant contribution of fertilizer from agriculture lands. Fluoride enrichment occurs in groundwater through the dissolution of fluoride-rich minerals. By reducing the consumption of fertilizer and stress over groundwater, the water quality can be improved.

*Original abstract online at https://link.springer.com/article/10.1007%2Fs12040-018-1006-4