Leachate from mixtures of fly ash and flue gas desulphurizing (FGD) residues were analysed by shake and column tests. The pozzolanic reaction between FGD and fly ash proceeds over a period of several months forming a dense structure with reduced leachability. High variations were found between different sources of ash and FGD.
Wahlström, M., Ranta, J., & Lindroos, P. (1990). Landfilling characteristics of flue gas desulphurizing wastes. Waste Management and Research, 8(6), 451-459. https://doi.org/10.1016/0734-242X(90)90020-N