Electric power plants that bum fossil fuels emit several pollutants linked to the environmental problems of acid rain, urban ozone, and the possibility of global climate change. Not only are gaseous and particulate emissions from coal-fired power plants of environmental concern, but also their. byproduct, fly ash may lead to contamination because of the possible release of both major and trace elements. Although there are serious efforts to use fly ashes as construction materials or soil amendments, the amount of the stocked waste ash keeps increasing because production exceeds the amount that can be used in the construction industry. Waste ash that cannot be used in above-mentioned industries needs to be disposed of. The safe disposal of waste ashes requires adequate identification and classification of their heavy metals as well as their toxicity levels. This paper summarizes the effects of the fly ash from coal-burning electrical utilities on ecosystems and provides information about how to beneficially use this kind of ash.