Fundamental study of effect of waste rock condition on control of acid mine drainage at open pit coal mine in tropical regions

Acid Mine Drainage (AMD) problem is considered as one of the serious problems in mining operation in the world. This problem is generated due to sulfide minerals in waste rocks. Sulfide minerals are very commonly included in any types of crustal rocks, resulting in AMD and a negative impact on the ecosystem. In this research, some experiments were conducted with the rocks sampled in the open pit coal mine in Indonesia to understand the effects of the rock condition on acidic water generation. The result indicated that wetting and drying process affected the disintegration of rocks caused by both physical and chemical factors in the rock sample. Hence, AMD generation is promoted due to both factors while waste rocks are stored in tailings in the current system. It suggests that the system for waste rock management should be improved to prevent AMD generation.