Hydrogeological Lab, Dept of Geology,Periyar University Salem-India

Email:-provnkdswrn@gmail.com

The Cumbam valley watershed, located in Uttamapalyam and a small part of Periyakulam taluk, the western corner of Teni District covers an area of about 890.97 Km², Tamilnadu, has been selected for this study. A multivariate statistical assessment has been adapted to the classification of a large, irregular dataset of 55 subsurface water samples in pre-monsoon 2009 and analyzed for various water quality parameters such as pH, EC, TDS, Ca⁺², Mg⁺², Na⁺, K⁺, HCO₃^-, CO­₃^-, SO₄^-2 and Cl^-. Hydrogeochemical data for 55 groundwater samples were subjected to Q- and R- mode factor and cluster analysis. R-mode analysis reveals the inter-relations among the variables studied and the Q-mode analysis reveals the inter-relations among the samples studied. The R-mode factor analysis shows that Mg and CI with CO₃ account for most of the electrical conductivity, total dissolved solids and total hardness of the groundwater. Both Q-mode factor and Q-mode cluster analyses shows that there is an exchange between the river water and adjacent groundwater. Cluster classification map reveals that 97.79% of the study area comes under cluster I classification