GIS-Based Study on Ground Water Trace Metals Contamination in Dhemaji District of Assam, IndiaAuthor(s): Mridul Buragohain and Hari Prasad Sarma
In present work, trace metal contamination of the groundwater in Dhemaji district of Assam was assessed. Thirty ground water samples were analyzed using Atomic Absorption Spectrometer, Perkin Elmer AA 200 model for their Copper, Nickel, Manganese, Zinc and Chromium content and their levels compared with WHO specified maximum contaminant level. Multivariate Geospatial analyses were performed, using GIS (Geographic Information System) techniques and statistical analysis with the help of SPSS® statistical package (Window Version 10.0). According to the WHO, the Maximum Permissible Level (MPL) for Copper, Nickel, Manganese, Zinc and Chromium are 1.5 mg/L, 0.02 mg/L, 0.5 mg/L, 5.0 mg/L and 0.1 mg/L, respectively. Analysis reaveled that none of the samples analysed contained Copper and Zinc in concentrations above the MPL. But water samples of the area fall under alert category with respect to Ni, Mn and Cr, as most of the analysed samples exceed and some are approaching the MPL of WHO. The Ni, Mn and Cr contamination of ground water in the study area needs proper attention.