Ecological Effects of Subsurface Mining
Surface mining techniques don’t work for extracting all valuable geologic resources. Diamonds and most metal ores, including gold, require extensive subsurface mines to access the rocks with these resources in them.
Subsurface mines are probably what you envision when you think of mining: systems of tunnels and vertical shafts with elevators to take miners underground where they can retrieve the valuable resources.
Subsurface mines produce large amounts of environmentally hazardous acid mine drainage. To keep the underground system of tunnels and mine shafts clear, mining companies have to pump out large amounts of water, which go into surface ecosystems. The groundwater from the mines is more acidic than surface waters and disrupts ecosystems by changing the pH conditions of soil and water sources.
Subsurface mining operations don’t create the visible changes in the landscape that surface mining operations do, but the conditions of subsurface mines are extremely hazardous for the working miners. The potential for accidental cave-ins, explosions, and fires is high. The air quality deep within the mines is poor; the atmosphere is rife with particulates and gases that lead to respiratory diseases, including lung cancer.
Some mining companies have begun to realize that keeping mining operations environmentally safe and clean from the start is more cost-effective. Mining corporations prefer to avoid the expense of cleanup and restoration or of being held legally responsible for ecosystem destruction or human health effects. Instead, these companies see that some investment into sustainable mining practices to begin with, saves them money in the long run.