Mining wastes can cause significant ecological destruction. Often, solid mine wastes are dumped into streams, destroying habitat and causing siltation and heavy metal and other contamination. Even when such wastes are stored out of water channels, trace materials can leach into surface waters and infiltrate into local groundwater. Fine- grained tailings can wash into local waterways and degrade streams by covering and filling coarser-grained substrates. Such sedimentation increases stream turbidity, decreasing net primary productivity and smothering the eggs of fish and other aquatic organisms, and it can alter stream flow dynamics. The pace of urbanization is increasing globally, putting more pressure.
