Hydrogeochemistry and multivariate statistical analysis of groundwater quality of hard rock aquifers from Deccan trap basalt in Western India

In the present investigation, hydrogeochemistry and multivariate statistical analysis of groundwater quality were assessed from hard rock aquifers of the Deccan trap basalt in the Jalna district of Maharashtra. Groundwater samples ( n = 105) were collected from the study area in a systematic grid pattern to avoid biasing in sampling. Water quality parameters of all these groundwater samples were analyzed by standard BIS and APHA procedures by titrimetric and using sensors. Uranium in all samples was analyzed using an LED fluorimeter. Strict quality assurance and quality control features were adopted in all stages of the study to ensure the quality of the data. The observed sequence of the dominance of major cations and anions is Ca 2+ > Na + > Mg 2+ > K + and HCO 3− > Cl − > SO 4 2− respectively. The observed uranium values were in the range of 0.1 to 16.2 µg/L with an average value of 2.04 µg/L, well below the safe limits recommended by WHO and AERB i.e. 30 and 60 µg/L, respectively. Piper trilinear diagram indicates dominant hydrochemical facies of groundwater in the study area are Mixed Ca 2+ –Na + –HCO 3 − , Na + –Cl − and Ca + –HCO 3 − while Gibbs plot infers host rock-water interaction is the major geochemical process in these aquifers. The correlation analysis, cluster analysis, and factor analysis tests are performed. Groundwater was assessed for its suitability for irrigation purposes using multiple indices such as SAR, RSC, and Na percentage. From the estimated indices, it was found that the groundwater in hard rock aquifers of the Deccan trap basalt is suitable for irrigation purposes.