Groundwater arsenic and fluoride in Rajnandgaon District, Chhattisgarh, northeastern India
The groundwater of Ambagarh Chouki, Rajnandgaon, India, shows elevated levels of As and F−, frequently above the WHO guidelines. In this work, the concentrations of As, F−, Na+, Mg2+, Ca2+, Cl−, SO4 2−, HCO3 −, Fe, dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) in the groundwater of Ambagarh Chouki are described. The sources of dissolved components in the groundwater are investigated using the cluster and factor analysis. Five factors have been identified and linked to processes responsible for the formation of groundwater chemistry. High concentrations of dissolved As seems to be linked to high concentrations of DOC, suggesting reductive dissolution of ferric oxyhydroxides as arsenic mobilization process. Fluoride is found in shallow depth water, presumably as a consequence of evaporation of water and removal of Ca2+ by precipitation of carbonates.