Research indicates that abandoned coal mines may be significant, overlooked sources of CO2 emissions. Acidic mine drainage dissolves carbonate rocks, releasing carbon into the air as water reaches the surface. In some cases, a small number of mines can emit as much CO2 as a coal-fired power plant. There is potential to mitigate these emissions by changing how mine water is handled. By keeping discharge underground or using subsurface treatment wetlands, the degassing process can be prevented. This shifts the view of mine remediation from simple water cleanup to a strategic carbon management tool.
