Serbia obtains most of its energy from low-quality lignite, thus being one of the world's largest producers of coal ash per capita. In order to examine the distribution of trace and major elements in the ash and the pollution potential of the ash itself, six combined samples of filter ash, obtained by lignite combustion in the Nikola Tesla A Power Plant, were subjected to a five-phase sequential extraction. Analysis of obtained concentrations revealed the short- and long-term pollution capacity of different elements as well as the influence ionic strength of river water may have to the pollution of neighboring waters.