(Why I would not swim or fish near Missoula in the Clark Fork at least a few years!)
Montana Dam Is Breached, Slowly, to Restore a Superfund Site
By JIM ROBBINS
MILLTOWN, Mont. — Milltown Dam, a symbol of industrial progress that became a symbol of destruction, was recently breached, and two parts of the Clark Fork River were joined again.
There was no dynamite, no wrecking balls, no “blow and go” removal. Instead, an earthen dam blocking a specially built channel was removed to allow a small trickle of water to flow through and gradually grow larger. The main part of the dam will be demolished over two years.

When the project is complete, it will cost $120 million.

Taking out the 1908 structure is the thorniest part of one of the largest toxic waste cleanups in the country, in what is known as the Clark Fork Basin Superfund Complex. The slow-motion breach at the end of March was intended to minimize the effects of releasing of sediment contaminated with heavy metals captured behind the dam.“The slower it goes, the better,” said Sandy Olsen, head of the remediation division in the Montana Department of Environmental Quality. “It’s not as dramatic. But there are fewer and less intense impacts on the fish.”

LINK TO CON.