159-Cluster Analysis of Groundwater Quality Data of Trombay Region, Maharashtra.

Abstract

This paper summarizes the findings obtained in a monitoring study to understand the sources and processes affecting the quality of groundwater in Trombay region using cluster analysis. Three distinct types of groundwater clusters were found, viz., Na—HCO3—EC—pH—SO4—Cl, Mg—Ca and Si02—K. These three different clusters indicate that different geochemical mechanisms control the chemical characteristics of the groundwater. The groundwater chemistry is mainly influenced by dissolution of minerals in the deep zone whereas base exchange dominates in the shallow zone. Enhanced mineralization in shallow zone compared to deep zone lindicate faster circulation of groundwater in deep zone preferably through fissures and fractures whereas groundwater flow is sluggish in shallow zone.