Cluster Analysis of Groundwater Quality Data of Venkatagiri Taluq, Nellore District, Andhra Pradesh

An assessment of the quality of groundwater for the Venkatagiri taluq of Nellore district has been carried out with an objective to determine the hydrogeochemical variability A total of 120 samples of groundwater were collected from wells distributed over different geological formations such as gneisses, schists, phyllites and quart7ites The groundwater samples were analysed for the major chemical constituents, viz Ca, Mg, Na, K (Cations), CO_y HC0₃, S0₄ CI (Anions), pH and EC Cluster analysis, a multivariate statistical tool, has been used in the study as a qualitative means for differentiating groundwaters into distinctive types Based on hydrogeochemistry, chemical variability deciphered from Cluster analysis suggests three distinct types of groundwaters, viz Mg-Cl-Ca type, Na-HCO, type and C0₃-pH type Distribution of these groundwater types and their quality have been found to be in direct relation with the host rocks of the area.