The American West is Full of Old Mines Threatening to Pollute Waterways

Lessons can be learned from the recent spill in the Animas River

Animas river
Animas River flowing through Santa Rita Park a week after the Gold King Mine spill in Colorado Hanna Maddera/Reuters/Corbis

Earlier this month, when clean-up efforts led by the Environmental Protection Agency accidentally resulted in a spill of millions of gallons of wastewater from a century-old mine into the Animas River of Colorado, it turned the water orange and alerted the nation to a problem in the West: There are tens of thousands of mines with the same potential.

The American West is full of what are called "hard rock mines" — mines designed to extract minerals like gold, silver, iron, copper and zinc. And each of those old mines has the potential to seriously pollute the environment, if not handled properly. A report issued Wednesday indicates that the EPA "lacked crucial information, including a reliable estimate of the volume of water inside the abandoned mine," reports Joby Warrick for The Washington Post. The report was written by EPA-appointed investigators.

While the report doesn’t explicitly say that the EPA made major missteps or was lax in some duty, it does show what could be done in the future. Warrick writes:

“Given the maps and information known about this mine, a worst-case scenario estimate could have been calculated and used for planning purposes,” the report stated. As it was, the EPA’s team was “lacking emergency protocols in the case of a significant flow or blow out,” the document said.

The EPA was attempting to drain an old mineshaft of contaminated water at the Gold King Mine when an unexpected collapse sent the water into the river. The contaminants in the water weren’t introduced by miners years ago, but rather the result of opening up the rock and exposing it to water and oxygen. The resulting chemical reactions produce acidic water that dissolves heavy metals that can be toxic to fish and insects, explains Jonathan Thompson for High Country News. Without the EPA’s clean-up efforts, that water would have seeped into waterways anyway. Fish have already been struggling in the Animas for years.

That same problem could be building in many other mines. For Clapway, Kerry Martin writes:

In Colorado, 230 of these have been slowly secreting their water into major waterways for years, and across the West, 40% of river headwaters are polluted by acid mine runoff. Even without the added pressure of cleaning up the Animas River mess and answering people’s demands, the E.P.A. has its work set out for it.

While the full effects of the spill on the Animas River have yet to be understood, perhaps the first can be the greater awareness that old mines are a problem stretching across the West.

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