Introduction to Coal Mine Drainage

Coal deposits are found on every continent. Most of these deposits have been or are being mined. China is the world’s largest coal producer, while the United States has the world’s largest reserves. The other most important coal-producing countries are Australia, India, South Africa, and Russia. Yet the nature of the coal mine drainage (CMD) from the various coal deposits and, indeed, even within the same coal deposits, varies significantly. In part, this is because of climate but also generally the paleoenvironment of the coal deposit – that is, what the region was like when the organic-rich sediment that became the coal was first deposited.