A new government study shows that Idaho’s Lake Coeur
d’Alene is one of the most contaminated bodies of water in the
world. The U.S. Geological Survey estimates that 85 percent of the
50-square-mile lake bed is contaminated with 75 million metric tons
of sediments containing silver, copper, lead, zinc, cadmium,
mercury and arsenic. The contamination comes from mining and
ore-processing in the Coeur d’Alene mining district between 1895
and 1910. Until 1968, most of the wastes were discharged directly
into the South Fork of the Coeur d’Alene River, which drains into
the lake. Although the EPA established the 21-square-mile Bunker
Hill Superfund site in 1983, the agency neglected contamination
downriver and in the lake. Today, the lake is popular with
recreationists, but most of the lake bed is devoid of life.
Copies of The Effect of Mining and Related
Activities on the Sediment Trace Element Geochemistry of Lake Coeur
d’Alene, Part I: Surface Sediments and Part II: Subsurface
Sediments can be obtained from Dr. Horowitz, U.S. Geological
Survey, Peachtree Business Park, Suite 130, 3039 Amwiler Road,
Atlanta, GA 30360 (404/903-9100).
* John
Rosapepe
This article appeared in the print edition of the magazine with the headline Idaho’s unsettling sediment.
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