Effective remediation strategies for ash dam sites in coal power plants

Pond ash is one of the main residual wastes from coal combustion. In coal power plants, the pond ash is usually mixed with seawater and stored as stockpiles, commonly known as ash dams. Once the ash dam ‘dries out’, the particles scatter with the wind, giving rise to various health issues. This research study aims to identify effective strategies for remediating the ash dam sites of coal power plants. Initially, the researchers conducted a literature review and expert interviews to identify strategies for remediation. The four alternatives are using (a) a sprinkler system, (b) Nu-Rock technology, (c) silicone extraction technology and (d) tree-planting technology. To validate the expert interview findings, this research quantified all the costs and benefits of the Port Augusta power plant in Australia as a case study. Silicone extraction technology and Nu-Rock technology create up to AU$20 million worth (AU$1 = US$0.718) of jobs within the area. Based on the analysis, it is identified that the Nu-Rock technology, silicone extraction process and plant regeneration alternatives are effective in ash dam remediation. The sprinkler system is a quick and temporary fix to ash dams until a permanent solution is introduced.