Hesperian Health Guides

Contaminated Water

In this chapter:

Mining uses large amounts of water and leaves large amounts of waste, contaminating water sources and the people who depend on them. While all mining operations tend to pollute water, big companies usually cause the biggest problems. Surface water and groundwater in mining areas may remain contaminated for many years. Water loss can leave the land barren and unusable for farming or raising animals. The long-term damage of water contamination will last much longer than the short-term economic gain from mining.

3 women speak as they collect water from a dirty river.
Since the mining company came, the amount of water in our river has dropped to almost nothing.
The water tastes terrible now.
I don't want to touch that water, but how else can I wash?

Preventing and reducing water pollution

Leaking waste ponds are one of the main causes of water pollution from mining. To prevent pollution, waste ponds should be:

  • built away from water sources or watershed drainage areas.
  • lined to prevent leaks into groundwater.
  • built according to the best international standards.
  • monitored to prevent leaks and spills.
  • emptied of wastes and safely closed when mining operations end.

Cleaning water once it has been polluted by mining is difficult, costly, and not always successful.

Community action saves a river

In the northern Philippines, the Abra River runs from high in the mountains through lowland farms and into the China Sea. For many generations, communities along the Abra River made their living from farming, fishing, handicrafts, and small-scale mining of gold and copper. In recent years, large corporations have begun mining the area’s gold, causing great harm to the river, the wildlife, and the people who live there.

2 men with a fishing net in a small boat.

Mining companies cleared forests to dig the mines, causing the river and the streams that feed it to fill with silt and dry up. Many kinds of birds, animals, and plants have disappeared. The river has been poisoned by chemicals spilled from waste ponds and from acid mine drainage. People living along the Abra River suffer from headaches, dizziness, coughing, chest pain, nose and eye irritation, skin rashes and diarrhea, as well as long-term problems like hunger from crop loss year after year.

In response to these problems, local people formed a group called Save the Abra River Movement (STARM). STARM protects land and water rights in many ways. STARM educates communities and government officials about the dangers of mining. It organizes petitions and rallies to make local demands known. It monitors water quality through a partnership with local universities, which contribute equipment and scientists, and local people’s organizations that act as witnesses, guides, and water collectors.

Armed only with cell phones and cameras, community-based water monitoring teams alert each other about unusual events. For example, when a lot of fish started dying downstream, community leaders upstream investigated and found that an a strange chemical smell was coming from the mine drainage. University scientists were alerted and quickly sent water containers so they could sample river water for toxics.

Dangerous mining continues along the Abra River. But the Save the Abra River Movement is forcing mining companies to stop the most harmful practices, and the communities are asserting their rights to a safe and healthy environment.

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 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.
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.
  • Learn how mines can be monitored, and involve the community in making sure they are safe (see Other Environmental Health Resources).
  • Insist that the only safe way to deal with acid mine drainage is to prevent it in the first place.
This page was updated:05 Jan 2024