In this present study the chemical changes of fly ash exposed to prolonged, large scale contact with sea water in the earlier ash dumpsite of Tuticorin thermal power plant in Tuticorin Bay was determined. The chemical characteristics of pH, organic carbon, calcium were studied by taking different ash samples at one time during May, 2015. Chemical changes of dumpsite ash was studied by comparing with fresh fly ash taken from electrostatic precipitator of thermal power plant. Two stations were fixed in and around the earlier ash dumpsite. Four trace elements (Fe, Cu, Pb & Cd) were studied for 3 ash types: ash from electrostatic precipitator, dumpsite ash (S1) and ash from station 2 sediment. The pH in dumpsite ash was decreased due to high temperature of dumpsite area, all the trace elements were high in fresh fly ash except iron. Chemical changes occurred in ash contact with sea water and altered the quality of seawater. The organic matter present in water may bring some of the trace element in water by means of chelation and complexation reactions. The present study revealed that the mobilizations of fly ash constituents were influenced by various environmental factors and further need to be studied in details.
