Animas River Disaster Leaves Mineshafts to Clean

On August 5th, 2015, contractors from the Environmental Protection Agency were cleaning polluted water out of southwestern Colorado’s long-abandoned Gold King mine shaft, when disaster struck: part of the mine collapsed under the water’s pressure, releasing over 3 million gallons of foul yellow sludge into the Animas River, staining the waterway for hundreds of miles.

Animas River Disaster Leaves Mineshafts to Clean - Clapway

What Exactly Was The E.P.A. Trying To Do?

It was just another day on the job. Contractors from the E.P.A. were attempting to drain a deposit of contaminated water from the mineshaft near Silverton, Colorado, as they have been slowly doing with thousands of mineshafts across the west.

Their task is the result of 150 years of shoddy mining regulations. During the 1859 Colorado Gold Rush and the decades following, prospectors would essentially blow holes in the sides of mountains, scrape out a bunch of rocks, and dump the less valuable stuff in a trench or valley somewhere. By 1872, people at least had to prove there were some metals in the places they were blasting. By 1891, mines were required to have a small amount of ventilation; by 1910, the US had over 2,000 mining deaths every year, prompting periodic, modest increases in health regulations. But the first environmental regulations didn’t kick in until 1948 with the passage of the Federal Water Pollution Control Act, which in 1972 became the Clean Water Act, enforced by the newly-formed Environmental Protection Agency.

But for the mining industry, the Clean Water Act was too little too late. Ambitious, blast-happy prospectors had been dumping their waste for over a century. Mine shafts, mountainsides, landfills, riverbeds, and every mountainous nook and cranny imaginable had already been filled with rocks and metals dug from deep underground. Whether or not they were dumped directly into existing bodies of water was irrelevant; mining waste pollutes the snow that melts off of it, the rain that falls on it, and the new bodies of water miners create by digging holes everywhere.

So it was just another day, and the E.P.A. was draining one of these deep holes from a 19th century mine now filled with water. But they underestimated the water pressure of the deposit and accidentally triggered a collapse, sending 3 million gallons of sick yellow goop into the aptly named Cement Creek, from which it flowed into the Animas River and formed a long, golden snake that sent the West into an uproar.

Foul Yellow Sludge: We Reveal It All

So what makes this water so bad? After all, it’s natural; it comes from the earth, right?

Human beings—and all living organisms—are adapted to drinking water with trace amounts of almost every mineral our planet’s surface. In fact, we would die without doing so. Those minerals enter our water by colliding and interacting with the earth’s crust, which is composed of—you guessed it—minerals.

But when that water is interacting with heavier metals dug up from deep beneath the earth’s surface, and especially when that water chills with these rocks for years on end as it does in mineshafts, would-be healthy minerals reach poisonous levels, and rarer metals that our bodies are not adapted to enter the water. Organisms benefit from the casual encounters of rain and rock, but long-term relationships between water and mine-waste prove toxic.

As such, the great yellow plume that came billowing down the Animas River contained poisonous levels of many minerals that would be healthy in trace amounts—iron, nickel, zinc, copper, cobalt, manganese, molybdenum, aluminum, and arsenic—and it also contained high levels of minerals that are toxic even in tiny doses: barium, cadmium, mercury, and lead. The water produced a foul smell, and was found to be as acidic as black coffee.

Ironically, the yellow color came from perhaps the healthiest mineral of the bunch: iron.

Three weeks after the disaster, these minerals and their color and stench are finally being washed out of the Animas River. But they will live on in the river’s fish, particularly trout: while few died, all now contain high concentrations of these deadly metals for years to come. It remains to be seen whether the lasting effects on the fishes’ health will outweigh the relief that no humans will be catching them again for quite some time—except to diagnose their health.

When You Turn the Animas River Into Mustard, People Get Upset

The Animas River was already a struggling ecosystem, having suffered from minor mine pollution, urbanization, and increasing demand for decades. Still, the Gold King catastrophe was jarring for those live in the region.

As the Animas River has slowly gone back to pre-spill levels, people’s fury has only escalated. Several towns and the Navajo Nation are demanding compensation from the Federal government as well as a thorough investigation into the E.P.A.’s handling of the incident, preferably by an agency other than the E.P.A.

For three weeks, towns in Colorado and New Mexico had their drinking water shut off. Farmers and ranchers were ordered to stop using their well water and irrigation ditches. The region’s recreational water-sport economy—kayaking, white-water rafting, fishing, etc.—suffered enormous losses during what is usually its most profitable time of year. Fishing tourism in the Animas River will suffer a lasting loss.

Despite the E.P.A.’s insistence that the Animas River is clean once again, the Navajo Nation has vowed not to use it for at least a year. Their suit against the E.P.A. asks the agency to compensate them for devastating the river that has long been their lifeline.

The Gold King Mine Is Just the Beginning

The Gold King is just one of thousands of abandoned mineshafts filled with contaminated water. 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.

The problem is, for such an pressing task, cleaning polluted water out of old mineshafts is an extremely difficult, dangerous, and expensive job.

There has long been controversy over an E.P.A. rule that holds anyone liable for contaminating a river, even an environmental organization who accidentally pollutes a waterway while trying to clean it. This rule has been criticized for scaring off well-meaning organizations and slowing down the cleaning process.

In some ways, the recent disaster has validated this rule by demonstrating the extreme difficulty and high stakes of cleaning these mines. At the same time, it has completely eroded much public trust in the E.P.A. Unhappy parties will demand that the E.P.A. is held as accountable as it would hold an outside organization, and they will likely continue petitioning for organizations to be allowed to clean mines without risking liability—since the E.P.A.’s cleaning of them is clearly a liability in and of itself.

Whatever happens, cleaning the West’s mineshafts will be a slow but steady process, since these particularly polluting types of mines are no longer being dug. But as Western droughts rage on and water supplies grow thinner and thinner, keeping that water clean will only grow more urgent.


Don’t take nature for granted. Let’s do our part to preserve it for generations to come:

Kerry Martin is a semi-native of Denver. He went to school in Vermont for its great beaches. Now transplanted to Brooklyn, he works as a volunteer coordinator/community organizer for ArchCare TimeBank when he isn't writing Ecology, Technology, and Offbeat articles for Clapway.