484 Mining and Health
Acid mine drainage
Acid mine drainage happens when water and air mixes with the sulfur deep
in the ground (sulfide) to create acids that dissolve heavy metals and other
toxic mine wastes. This toxic mixture eats away at rocks and goes into the
soil, groundwater, rivers, and lakes. At first, there may be few signs of danger,
but slowly the poisons in the water sicken people, plants, fish, and animals.
Acid mine drainage destroys life downstream from a mine for hundreds or
even thousands of years.
Any mine can create acid mine drainage. Because it is nearly impossible
to stop, companies should prove before opening a mine that there is no
sulfide in the ground so there will be no acid mine drainage. Clean-up or
containment of acid mine drainage is so costly and difficult that even in
countries with strong environmental laws, thousands of kilometers of river
are contaminated. A campaign against acid mine drainage may prevent a
company from opening a mine in the first place.
Mine pit
When soil is removed,
rainwater, air, and sulfide mix
to create acid mine drainage
(sulfuric acid and heavy metals).
Acid mine drainage poisons water downstream and is nearly impossible to clean up.
Take action against acid mine drainage
• Identify abandoned mines and have them tested by trusted scientists.
Do not let the mining company do the tests and simply tell you the
results. They lie.
• Demand the mining company provide an Environmental Impact
Assessment report that includes acid mine drainage (see page 560).
• Learn how mines can be monitored, and involve the community in
making sure they are safe (see Resources).
• Insist that the only safe way to deal with acid mine drainage is to
prevent it in the first place.
A Community Guide to Environmental Health 2012