A Case Study of Environmental Policies and Guidelines for the Use of Coal Ash as Mine Reclamation Filler: Relevance for Needed South Korean Policy Updates

The South Korean government is pursuing a national project to use the complex carbonates found in coal ash to capture CO2 and promote coal ash recycling. One possible approach is the use of coal ash as fill material in mine reclamation, but environmental concerns have so far blocked the implementation of this procedure, and no relevant regulations or guidelines exist. In this study, we review international approaches to the environmental management of coal ash recycling and consider how the lessons learned can be applied to South Korea. Each studied country was proactively using coal ash for beneficial uses under locally suitable conditions. The United States, European Union, United Kingdom, Australia, and Japan are all putting coal ash to beneficial use following thorough analyses of the environmental impact based on several considerations, including bulk concentration, coal ash leachate concentration, field inspections, and water quality monitoring. Our findings can contribute to the development of proper regulations and policies to encourage the use of recycled coal ash in South Korea as an approach to managing carbon emissions and climate changes. There are currently no relevant regulations in South Korea, so we consider the adoption of the strictest standards at each stage of the other cases at the time of introduction. Based on our findings, detailed and appropriate management guidelines can be developed in the future. Establishing management plans for complex carbonates, verifying their environmental stability, and using them as fill material will provide clear benefits for South Korea in the future.