3. Mining activities: Mining is the process of crushing the rock and extracting coal and other minerals from underground. These elements when extracted in the raw form contains harmful chemicals and can increase the amount of toxic elements when mixed up with water which may result in health problems. Mining activities emit several metal waste and sulphides from the rocks and is harmful for the water. - See more at: http://www.conserve-energy-future.com/sources-and-causes-of-water-pollution.php#sthash.vrnQ21oZ.dpuf