pH Dependent Leaching Behavior of Zn, Cd, Pb, Cu and As from Mining Wastes and Slags: Kinetics and Mineralogical Control

From the Middle Ages until the beginning of the twentieth century, extensive Zn–Pb mining and smelting was carried out in East-Belgium. By lack of waste treatment techniques and sustainable management practices, metal-bearing slags and unprocessed waste were dumped in huge tailings, which still represent an important source of contamination. A chemical and mineralogical characterization of different types of mining waste originating from the former Pb–Zn mining industry was performed in order to gain a better understanding of the slag properties, with special attention to heavy metal release under varying pH conditions, and to bring this in relation to different management scenarios.