Multivariate statistical techniques for the evaluation of groundwater quality of Amaravathi River Basin: South India

The study of groundwater in Amaravathi River basin of Karur District resulted in large geochemical data set. A total of 24 water samples were collected and analyzed for physico-chemical parameters, and the abundance of cation and anion concentrations was in the following order: Na+ > Ca2+ > Mg2+ > K+ = Cl− > HCO3 − > SO4 2−. Correlation matrix shows that the basic ionic chemistry is influenced by Na+, Ca2+, Mg2+, and Cl−, and also suggests that the samples contain Na+–Cl−, Ca2+–Cl− an,d mixed Ca2+–Mg2+–Cl− types of water. HCO3 −, SO4 2−, and F− association is less than that of other parameters due to poor or less available of bearing minerals. PCA extracted six components, which are accountable for the data composition explaining 81% of the total variance of the data set and allowed to set the selected parameters according to regular features as well as to evaluate the frequency of each group on the overall variation in water quality. Cluster analysis results show that groundwater quality does not vary extensively as a function of seasons, but shows two main clusters. © 2017, The Author(s).