Abstract

Fifty-one groundwater samples were collected during South-west monsoon 2009 from Challaghatta, Vrishabhavathi, Kormangala and Hebbal valleys, Bangalore, which is an unconfined/crystalline aquifer to investigate Fe, Mn, Cu, Zn, Pb, Cd, Cr, Ni concentrations and other parameters like temperature, pH, electric conductivity (EC) and total dissolved solid (TDS). The TDS and EC variation confirmed light-salty nature of groundwater found to be contaminated by Salty water intrusion, which is attributed to over-extraction. Comparison between presence, abundance and frequencies of trace elements in groundwater samples is in the order of Fe (84) > Zn (72) > Mn (68) >Pb (45) >Cu (41) >Cr (35) >Ni (33) >Cd (21), indicating that Fe in groundwater is in origin. The TDS, Pb, Fe, Mn and Cd concentrations in groundwater samples are beyond the permissible limit prescribed by World Health Organization (WHO).

Key words: Groundwater, heavy metals, lithologic physico-chemicals, sewage.