Improper Deposition of the Mining Waste as a Source of the Environmental Pollution: Case Study of the Lake Robule (Bor, Eastern Serbia)

Abstract

Lake Robule is an extremely acidic water body located in the proximity of the town of Bor (eastern Serbia) polluted with high concentrations of dissolved metal cations. Polluted water drains from the lake into the Bor river. Acid mine drainage originates on the slopes of the mine overburden deposit named Visoki planir located on the banks of the Lake. Long term exposure of the pyrite in the overburden to oxygen and water led to generation of the acid mine drainage. These acidic streams leach and mobilize metal cations, which end up in the lake Robule, making this water body extremely acidic and contaminated with metal cations. This situation could be avoided by proper deposition and reclamation of the mining waste. Inadequate deposition of the overburden of the Copper mine Bor and its impact on environment were analyzed in this paper. Reclamation of the mining waste usually consists of technical and biological phases, where terracing, stabilization, melioration and binding of mine waste occur. The quality of technical reclamation can often have a decisive impact on the quality of biological reclamation, surrounding environment and acid mine drainage generation process. In the copper mine basin in Bor, technical reclamation was carried out only partially and by forming high waste piles with narrow slopes. That has significantly limited the chances for successful biological reclamation of the terrain, and the consequences of this procedure were strongly eroded waste pile slopes without drainage channels, with almost complete absence of spontaneous vegetation, leaving sulfide minerals in the pile permanently exposed to water and oxygen.