Acid mine drainage occurs when rainwater reacts with sulfide minerals, forming acidic water that can harm ecosystems.

Acid mine drainage (AMD) is an environmental issue caused by the reaction of water, oxygen, and sulfide minerals like pyrite (iron sulfide) exposed during mining operations. This reaction produces sulfuric acid, which can leach heavy metals from surrounding rocks, contaminating water sources. The acidic and metal-laden water adversely impacts aquatic ecosystems, reduces water quality, and poses risks to human health. Commonly associated with coal and metal mining, AMD remains a significant challenge. Preventative measures, such as proper waste management, neutralization with alkaline materials, and land reclamation, are essential to mitigate its long-term environmental effects