The Relationship Between Mine Process Tailings Mineralogy and Pore Water Composition

Old tailings from Zn, Au, Cu, and Ni mining operations were characterized. Their mineralogical variation in depth is compared with matching pore water and solids chemistry. A geochemical model was used to predict minerals precipitating from pore water solutions. These are compared with actual secondary minerals occurring. The degree to which the precipitation of secondary minerals controls the sulfate and iron concentration of the pore water was also investigated. The results obtained are related to the selection of the most appropriate modes of tailings deposition.