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Animas River Spill A Stark Reminder Of Colorado's Mine Pollution Legacy

Orange wastewater flows from the Gold King Mine, Aug. 7, 2015. The Environmental Protection Agency inadvertently caused a spill while working to clean up the mine.

Say the names of these Colorado towns out loud: Silverton. Leadville. Silver Plume. Rico. Bonanza. Ironton. The last two are ghost towns, but the names of each allude to a history that - most of the time - is nearly invisible to most of the state's residents.

That mineral-rich past burst into the public consciousness after Environmental Protection Agency workers mistakenly triggered a release of contaminated water from the Gold King mine just above Silverton. The rust-colored water, laden with iron and several heavy metals, including very high concentrations of arsenic and lead, oozed its way down the Animas River, through the town of Durango and into New Mexico and beyond.

In the spill's wake, many questions have been raised. One is, just how big is the scale of mining wastewater problems in Colorado? Another is, what is being done to clean them up?

Look at a map plotting abandoned mine lands across Colorado, and you'll see a Jackson Pollock-esque spray of colored dots - gold, silver, lead, uranium - scattered atop and between mountain ranges. Colorado has a whole branch under its Department of Natural Resources called the Inactive and Abandoned Mine Reclamation Program. The head of the branch, Bruce Stover, said the state has been working for years to address the issue of pollution from approximately 22,000 abandoned mines.

Credit courtesy of Ecoflight / used w/ permission
used w/ permission
The Gold King Mine two days after the spill. EPA officials put in retention ponds and are treating the water to remove some contaminants before it enters the Animas River.

"We try to go in and characterize which mines are the worst offenders. Is it this drain over here, is it that waste pile over there? And we try to do projects that incrementally chip away at the overall problem," said Stover.

The work is certainly incremental. When asked how long it would take to clean up even three-quarters of the mines leaking hazardous materials, Stover sighed, and said "decades. It's just going to take a long time."

That's partly because there's not nearly enough money to pay for cleanups. Stover notes most of these mines don't have owners now. So there's no responsible party to foot the bill.

"It's a huge problem in Colorado because these are old, abandoned active mines and they don't have any owners and they are just draining."

Which gets to the next issue: who pays for cleaning up mines without owners?

Turns out, it's you. The funding for cleanups, according to Stover, comes largely from the Environmental Protection Agency. Sometimes it's under Superfund, but more often it comes from funds that help states meet Clean Water Act standards.

"The state doesn't really have the money to tackle these draining mines," Stover said.

Neither state nor federal agencies were able to provide a list of all the streams in Colorado impaired by acid mine drainage, which often causes high acidity and heavy metal concentrations. EPA data from 2010 does give a sense of the problem's scope, though. The agency reports 200 miles of streams in the state were too acidic to meet Clean Water Act standards. On the metals side, over 1,000 miles of streams in Colorado exceeded Clean Water Act standards for copper. Other metals that leach from mines, like lead, zinc, cadmium and arsenic are also causing problems in many hundreds of miles of streams.


Trout Unlimited is one nonprofit that has worked with state and federal agencies on mine cleanups across the state. When I reached Jason Willis, a mine restoration project manager, he was at 11,800 feet and about 50 miles west of Denver, working on a mine cleanup above Georgetown.

"We're doing construction in conjunction with the Forest Service in the Leavenworth Creek watershed, which is the water source for Georgetown and South Clear Creek reservoir," Willis said.

The abandoned mine problem spans an area known as the Colorado Mineral Belt, stretching from the San Juans and historic mining towns like Silverton and Telluride up through Leadville and into Summit County, and down into the Clear Creek area.

Of course, the problem is not unique to Colorado, added Willis. It affects headwater streams, the sources for rivers across the West, affecting the bugs and fish that live in those waters. At larger mine release sites, states and governments have put in costly water treatment plants to clean up water before it flows into rivers and drinking water sources. Colorado has several such treatment plants; some are Superfund sites and others, like the Leadville Mine Drainage Tunnel, under the control of the Bureau of Reclamation, are run by other agencies.

Cleanup Is Complicated

While it's easy to fault the EPA for causing a massive spill when working to clean up an old mine, many mining experts and those familiar with mine cleanup point out that accidents and unforeseen circumstances are, while not commonplace, certainly not unexpected.

Credit EPA
The Gold King Mine entrance is full of acidic wastewater containing iron, arsenic, lead, cadmium and other heavy metals.

"When you are working within an abandoned, inactive mine that people haven't been in for 20 or 30 years, it's a dynamic condition that changes every day," said the state's Stover. "You've got water coming in, you've got collapsing. It's risky business."

Jim Kuipers, a mining environmental engineer from Montana who has worked on cleanups across the country, agreed that cleanups always involve the potential for an accident.

"Sometimes, such as [what] happened this week, in the course of cleanup you have always a risk that this kind of thing can happen," Kuipers said.

Even some in Durango, where the river turned orange, agreed that it's unlikely the EPA did anything negligent. Ty Churchwell, a member of the Animas River Stakeholders Group who works for Trout Unlimited on cleaning up abandoned mines in the area said "anyone could have caused" the release.

"Anyone fiddling around up there possibly could have triggered this event. That could have been the mine owner himself, a state or federal agency, a county official up there just looking around."

Kuipers, the Montana engineer, also stated that while 3 million gallons is a "significant amount" of waste water, mines that are already leaking discharge that amount over a longer period of time. The mines the EPA was working on were discharging between 200 and 300 gallons per minute prior to the spill, according to the agency. At the minimum rate, that's a discharge of 2 million gallons of wastewater in a week.

A Complicated Cleanup History

The story of an earlier mine cleanup highlights just how hard it is to stem the problem of mine wastewater. The two mines the EPA was working on above Silverton, the Gold King and Red and Bonita Mine, are part of a network of tunnels bored by miners into the mountains above the town.

Until the early 2000s, those two mines, and two more up in the area, were more or less dry. That means the heavy metals deep inside were, overall, staying put. That changed after a cleanup in the vicinity, spearheaded by Sunnyside Gold Corporation, once the major employer in Silverton.

The cleanup wasn't without controversy, as Westword reporter Alan Pendergast reported in 2005. Sunnyside brokered a deal with the Colorado Department of Public Health and Environment where it plugged the American Tunnel below the Red and Bonita and Gold King mines, among other cleanup efforts in the area. That halted mine drainage from that tunnel, resulting in better water quality in the river below Silverton.

"It's a huge problem in Colorado because these are old, abandoned active mines and they don't have any owners and they are just draining."

But, as Ronald Cohen, an environmental engineer from Colorado School of Mines points out, "water has this nasty habit of finding the path of least resistance." If one tunnel is plugged, the water builds up higher and higher, and finds the next available outlet.

"And the next thing you know, it's coming out of the mountain again," said Cohen. "And that's what EPA has been trying to contain in all of these old mine workings, these abandoned mines."

After getting flak for a cleanup that ostensibly caused water to run out of once-dry mines, Sunnyside transferred its treatment responsibilities to another company, along with some cash to pay for treatment. That treatment only lasted for a year until the new company, Gold King, ran out of cash. So even when a mine has an owner, that doesn't appear to mean cleanup is guaranteed.

For its part, Sunnyside has said its tunnel was leaking water that stemmed from those mines above it in the first place. Bruce Stover, with the state's reclamation program, said that is a fair point.

"Fifty years that the American Tunnel was in existence, these two historically draining mines weren't [draining]. And now that you plug that tunnel back up [and the mines start draining again]."

In essence, you plug the lowest hole in a leaky barrel, said Stover, and the hole above it starts leaking again.

"So everybody has been up there working to take care of the next lower holes in the barrel. And that's where we are today."

Whether Sunnyside should have done a better job with its cleanup appears to be an open question. Another question is whether Silverton should have agreed to Superfund status years ago, rather than fighting fiercely against it.

Cohen, the engineer with the School of Mines, and many others have noted that with Superfund comes cash – and with cash, comes better cleanups.

That, perhaps, is the take-home from a tragedy like this, Cohen said.

"What it says to me is that the resources that should be going into the cleanup effort for dealing with these issues is certainly not commensurate with the severity of the issues. There needs to be more bucks."

Stephanie Paige Ogburn has been reporting from Colorado for more than five years, primarily from the Western Slope.
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