Assessment of heavy metal pollution in groundwater with respect to distance from ash pond by using heavy metal evaluation index

In order to assess the quality of groundwater near ash pond of Parichha Thermal Power Plant (Jhansi), heavy metal evaluation index (HEI)was calculated. An unlined ash pond is being used for a long time to dispose fly ash generated by thermal power plant. To assess the level of groundwater contamination due to ash slurry disposal, both groundwater and ash slurry samples were collected and analysed in terms of their chemical concentration. In the present study, it was observed that significant amount of trace elements can leach out from ash slurry and may contaminate groundwater due to downward percolation through soil strata in an unlined ash pond. Obtained results revealed the range of heavy metals concentration in groundwater as [Ni (0.02–0.07 mg/l), Pb (0.14–0.41 mg/l), Fe (0.20–7.21 mg/l), Mn (0.01–0.14 mg/l), Cr (0.03–0.05 mg/l) and Al (0.05–0.26 mg /l)]. HEI showed a heavy load of metal pollution within the range of 5 km from the ash pond while moderate pollution within the range of 7 km and very low at a distance of 15 km.