The Subterranean Water Cannons of Leadville, Colorado

There was a fascinating article in the New York Times yesterday about a mine disaster just waiting to happen.

[Image: "Abandoned equipment stands in the snow near the top of an underground tunnel that was once used to drain mine water." Photo by Kevin Moloney for The New York Times].

In Leadville, Colorado, we read, people now wake up every morning wondering if they "will be washed away by toxic water that local officials fear could burst from a decaying mine tunnel" on the edge of town.

For years, the federal Bureau of Reclamation and the Environmental Protection Agency have bickered over what to do about the aging tunnel, which stretches 2.1 miles and has become dammed by debris. The debris is holding back more than a billion gallons of water, much of it tainted with toxic levels of cadmium, zinc and manganese.

The article continues, describing the background for this "potentially catastrophic release of water":

Abandoned mine shafts honeycomb the surrounding hillsides. The old drainage tunnel, built by the federal government in 1943 to drain hundreds of these shafts, began falling apart in the 1970s, causing water to pool. In 2005, the E.P.A. offered to start pumping the clogged water toward a Bureau of Reclamation plant, which treats the water flowing through the tunnel; but the bureau contended that the additional water was part of the E.P.A.’s Superfund cleanup responsibility.

And so nothing was done. The threat of "release" is now so great that property in the town can no longer be insured.
One wonders if it might be possible to build something like this deliberately, as a military tactic: a kind of long-delay, underground water cannon that only fires once, several decades after construction.
You leave a few dozen of these things lying around, beneath a terrain you have to evacuate... and so whenever your enemies move in, they've got some rather big problems beneath their feet.