Summit County Citizens Voice

A population of young brook trout in the Snake River could be threatened by increasing concentrations of toxic metals during low-flow seasons.

Concentrations increasing seasonally, USGS research shows

By Bob Berwyn

SUMMIT COUNTY — Signs that water quality in the Snake River may be getting worse have once again spurred talks about an EPA Superfund cleanup at the abandoned Pennsylvania Mine, along Peru Creek.

Reclamation experts with the federal agency’s regional office say a Superfund designation could be the best way to get the money needed for a comprehensive cleanup, but some local officials aren’t sure they want the environmental stigma of a Superfund site in their backyard — or a massive industrial water treatment facility and a major service road in the Peru Creek backcountry, which has been the focus of long-term open space preservation efforts.

There are also questions about the effectiveness of point source treatment at the mine. What if you plug it up with a bulkhead and then the water starts seeping out somewhere else in the complex sieve of tunnels and shafts. Finally, there are questions about who would be responsible for the long-term operation and maintenance of a major water treatment plant high in the valley.

But focusing resources through the Superfund program could be the best, and maybe the only option to do some sort of meaningful remediation in the tainted basin, especially as some of the latest studies show continued degradation of water quality.

“In certain months, the peak concentrations for metals have been increasing … They’re creeping up and we don’t know why,” said U.S. Geological Survey researcher Andrew Todd. “Right now, it’s just looking at dots on a plot,” he said.

Since the Snake River has been closely monitored for decades, it’s unlikely that the data is misleading. And increasing concentrations of metals during low-flow months in the fall and spring, just before snowmelt, could be bad news for the few fish that do survive from year to year in the river. If the levels reach acute toxicity levels and stay there for even just a couple of weeks, it could be enough to kill fish in the river that already survive on the brink.

Of special concern is zinc, which is especially toxic to trout, but lead, manganese, arsenic and copper are also in the water, the typical stew in drainages affected by mine waste. Peru Creek is biologically barren, even above the Pennsylvania mine. A couple of miles downstream, it mingles with the clean water of Deer Creek, and all of a sudden, there is hope. When the North Fork burbles in, near the heart of Keystone Resort, there is life.

Sampling just last week found a new population of small brook trout in the Snake, near Keystone. Nearly all the fish in the river were killed in 2007, when a big rainstorm sent concentrations of metals spiking well above the already high ambient levels. Colorado Division of Wildllife biologist Jon Ewert said the river may be slowly rebounding from the toxic flood, but seasonal spikes in metals concentrations could be a limiting factor in any recovery.

Most of the metals pollution in the Snake comes from Peru Creek, both from abandoned mines in the basin, as well as from natural sources, as water trickles over highly mineralized rocks. Concentrations are so high that Peru Creek is biologically barren, with no fish or aquatic insects in the tainted water. Even several miles downstream at Keystone, the concentrations of metals exceed state and federal limits set to protect aquatic life.

The pollution in Peru Creek is so intense that there’s probably little chance of establishing a self-sustaining fishery directly in that tributary. Even with a cleanup at the Pennsylvania Mine, many other sources of pollution, including natural ones, remain.

“I think even with a cleanup, you’d have a biologically dead situation up there,” said Steve Swanson, head of the Blue River Watershed Group.

The local grassroots organization has been working toward some low-tech remediation projects, like moving waste rock from the mines away from the water. Even simple steps like that can prevent hundreds of pounds of metals from dissolving into the stream each year. But the crux of the Snake River dilemma has always been the Pennsylvania Mine, a rich producer of ore during the boom years, more than 100 years ago.

Three such projects were slated for this summer with EPA grant funds administered under a state program, but Swanson said implementation was delayed by a re-organization within the state mining agency.

As part of its work, the watershed group last year also completed a study of the Snake River basin, concluding that there is so much natural pollution that it’s unlikely that Peru Creek could ever sustain a fishery. Swanson said the group doesn’t — but should — have a seat at the table when it comes to Superfund decisions.

But at least some of the experts are convinced that they could design and build a functional treatment system that would reduce metals loading downstream, with the ultimate goal of establishing some sort of self-sustaining fishery in the reach from Keystone downstream to Dillon Reservoir.

Some people point to the water treatment plant at the abandoned Wellington-Oro Mine, in French Gulch, as a possible model for success. Since that facility started operating, cutthroat trout have been spotted in French Gulch as it flows through the Wellington neighborhood, according to Colorado Division of Wildlife biologist Jon Ewert.

Filed under: Environment, rivers, Summit County Colorado Tagged: | acid mine drainage, metals pollution Snake River, Summit County Colorado, Summit County News