It is known that the concentration of elements of fly ash varies due to the used-coal and the used-lime qualities varying in different periods. In the Can Thermal Power Plant (CTPP) located at northwestern Turkey, Can (Canakkale) basin coals, which are classified as lignite to sub-bituminous C coal with high total sulphur (0.4-12.22%) and a broad range of ash contents (3.2-44.6%) are mainly used. Performed studies reveal that some toxic elements exit in the coal, including As, U and V. Also, while the As, Cu, Co and Hg contents in coal increases, the sulphur contents in coal also increase. Additionally, trace elements that have inorganic compounds in coal are mobilized into air during the combustion process. This poses a big risk for human health and keeping the environment when Can Basins low quality lignite is burned, it's the fly ash that contains several toxic elements which can leach out and contaminate the water resources.