Abstract: This paper deals with the pollution originating from one of the by product of the coal called ash in Indian thermal power stations. Ash is obtained by the combustion of coal. This ash is again divided into two types based on its characteristics namely- fly ash, bottom ash. Mainly this ash can be used but not 100%. So rest of the ash which is not used is mixed with water. This mixture is called as slurry which is pumped to the ash pond. Some pollution is created during this process and after. Pollution caused by this assessed by taking samples. samples consists of the ash taken as soon as combustion takes place, other set of samples from ash pond. Samples extracted with Deionized water, a solution of potassium chloride and a solution of hydrochloric acid, the differences were compared in order to predict potential pollution.