Leadville: Separating the facts from the fears
Vail, CO Colorado
LEADVILLE, Colorado ” Three weeks into Lake County’s State of Emergency, as the science begins to settle out of the politics, it appears that some of the initial LMDT assumptions made by numerous elected officials may not have been completely
The officials were right to want to fix the tunnel, say experts ” but for some of the wrong reasons.
In the first few days of the State of Emergency, Lake County Commissioners and state Senator Tom Wiens stated that the above-average snow pack would lead to huge volumes of water infiltrating the mine pool in the spring.
However, according to a 2006 study done by Environmental Protection Agency (EPA) groundwater expert Mike Wireman, Source-Water Consulting president Jord Gertson and Dr. Mark Williams of the University of Colorado, it takes anywhere from five to 15 years for snow to make its way to the tunnel.
Thus, the chances that this year’s snowfall will lead to a significant rise in the mine pool this spring is highly unlikely.
Also, the mine pool is always highest in the fall and lowest in the spring, according to the study.
In fact, says Wireman, the tunnel’s high water level has been rising by about 10 feet every year since they started measuring in 2005–always in the fall. This year was no different.
The commissioners also argued that the blockage in the tunnel was directly contributing to an increase in the mine pool (a spongelike mixture of dirt and water well below the earth’s surface)–and that the growing mine pool could result in the collapse of a substrate of earth, possibly flooding the east side of town.
The contention led to the now-famous Associated Press headline “Town fears avalanche of contaminated water,” in addition to a run on flood insurance from local property owners.
But Wireman thinks the connection between the mine pool and the tunnel has been overstated.
He does agree that if water enters the tunnel and hits a back-up caused by a down-tunnel blockage, some of it may find its way to the mine pool.
“But I don’t believe that’s very much at all,” he says.
If Leadville experiences any land movement related to mine pool levels, it would be in the way of small sinkholes, he says.
“You’re not looking at 50 acres collapsing.”
By the time the sirens were tested at the Village at Lake Fork, even Lake County had backed away from its earlier concerns about a collapse on the east side of town, with Lake County Emergency Manager Jeff Foley stating that a release above Leadville was “unlikely.”
The commissioners also backed their declaration of a State of Emergency with the statement that metal-laden water trapped behind the collapse in the tunnel was migrating to California Gulch, creating new springs and seeps.
Those seeps, they said, are causing cadmium and zinc levels in California Gulch to rise.
But the seeps and springs may not be a result of rising water in the tunnel, say experts.
“Those seeps and springs are, frankly, to be fully expected,” says Wireman.
According to Wireman, even after the water levels in the tunnel go down, Lake County is likely to see seeps in California Gulch. He explains that groundwater always wants to rise to the surface–and in California Gulch, rising to the surface happens to be an easy thing for water to do.
Two things combine to make it easy for the water to come to the surface in the gulch, he explains: a fault that carries water easily, and the fact that not much dirt sits between the groundwater and the surface.
California Gulch never had a glacier, and so there isn’t much glacial outwash on top of the bedrock.
Leadville resident and hydrogeologist Kato Dee examined the water quality reports at the Colorado Mountain College library and explains this year’s levels of zinc and cadmium are within the statistical averages for the last six years. Though they are high by the Colorado Department of Health and the Environment’s cold water standards, he says, they have significantly decreased since the mid-1990s.
Asked how concerned people should be about the elevated metals, Environmental Protection Agency (EPA) remedial project manager Stan Christensen explains that fortunately, Lake County water has high levels of calcium and magnesium–both of which help protect aquatic animals from the effects of metals.
He doesn’t think metal-loading from California Gulch is adversely affecting the Arkansas River, but points out that it can be very hard to directly link something like an increase or decrease in fish population to a small source of metals, such as the seeps.
Part of the confusion around metal levels may have been that officials were basing their concerns on the fact that levels of cadmium and zinc in California Gulch were significantly higher than those the LMDT Treatment Plant is allowed to discharge.
But Dee and Christensen both explain that treatment plants have much stricter requirements than the average gulch.
Cleaning up an area where pollution arrives from many different sources is difficult, says Dee ” “and you can’t build treatment plants all over the place,” so realistic standards have to be set.
Perhaps the only thing not being questioned is whether or not the tunnel needs to be fixed.
Reclamation comes the closest to being skeptical, taking the position that, according to their experts, there isn’t a risk, says public affairs officer Peter Soeth.
But most experts agree something needs to be done.
Wireman explains that all involved need look at only two things: that water in the tunnel is rising and that tunnel grows older each day.
“I think they’re [the commissioners] are right to raise concern. The risk is increasing with time,” says Wireman.
But as for scientific missteps by government officials, Wireman is careful not to lay blame.
“They’re not scientists,” he points out.
But Dee thinks the commissioners should have been more careful to use well-proven facts.
He worries, for example, that once the tunnel issues are resolved, Leadville will be forced to defend itself against concerns about water quality in the Arkansas River.
When people bring tenuous scientific evidence into a discussion, he says, they generally open up more cans of worms than they meant to.
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