Fly Ash Disposal in Ash Ponds: A Threat to Ground Water Contamination

Ground water contamination due to deposition of fly ash in ash ponds was assessed by simulating the disposal site conditions using batch leaching test with fly ash samples from three thermal power plants. The periodic analysis of leachates was performed for selected elements, Fe, Cu, Ni, Cr, Pb and Cd in three different extraction solutions to determine the maximum amount that can be leached from fly ash. It was observed that at low pH value, maximum metals are released from the surface of the ash into leachate. The average concentration of these elements found in ground water samples from the nearby area of ash ponds shows that almost all the metals except ‘Cr’ are crossing the prescribed limits of drinking water. The concentration of these elements at this level can endanger public health and environment. © 2016, The Institution of Engineers (India).