Simulating drainage quality of sulfide mine tailings ponds

The Xiangxi gold mine was taken as an example to illustrate the application of the finite element and updated Lagrangian approach in the simulation and prediction of the quality of tailings effluents. The numerical modeling results suggest that tailings-water interaction at the early stage leads to the acidification and release of heavy metals which are responsible for the persistent pollution to the environment for 30 years. Tailings pore water can be gradually neutralized and contents of polluted species tend to decline markedly with time. The gangue dissolution and organic matter reaction can stimulate acid neutralization and decrease the diffusion rate of oxygen in tailings impoundments. The contents of pore-water species in upper tailings are significantly higher than in lower part and change severely at 6 m depth. Therefore, the hydrological zoning phenomenon in tailings impoundments accounts for geochemical zonation. This model has the potential to predict drainage quality of sulfide mine tailing impoundments.