San Francisco —

The federal Clean Water Act cannot be used to destroy an Alaskan lake, a federal appeals court said today, in a ruling that may set precedent about how the Act is interpreted nationwide.

Although the full ruling is not yet released, the Ninth Circuit Court of Appeals said the U.S. Army Corps of Engineers was wrong in letting a gold mine company dump toxic mine tailings into a lake near Juneau.

“In issuing its permit to Coeur Alaska for the use of Lower Slate Lake as a disposal site, the Corps violated the Clean Water Act,” the court said in the first of a two-part ruling on Kensington Mine dumping operations.

Today’s ruling disallowed a diversion ditch which the court said was environmentally destructive and which violated a previous injunction against the mine. But, the court said it would rule against the entire dumping procedure in its final opinion.

The ruling should prevent mines across the United States from likewise dumping into lakes, streams and rivers, said Tom Waldo, attorney for Earthjustice, a non-profit law firm that filed the appeal on behalf of citizen and conservation groups.

“The Kensington permit was a test case by the Bush Administration to resurrect destructive mining practices from the pick-and-shovel days,” Waldo said.  “We’ve learned from the mistakes of the past. The Clean Water Act prohibited these practices, and today’s court ruling confirms that.”

Waldo expressed hope that the court ruling would deter such operations elsewhere in Alaska — notably the proposed Pebble Mine in Bristol Bay, home of the world’s largest sockeye salmon fishery. Pebble Mine, like Kensington, is designed to dump vast quantities of toxic mine tailings into lakes. A broad coalition of business, environmental, fishing and native groups is opposing the mine because of its damaging potential.

In 1982, the Environmental Protection Agency (EPA) adopted regulations under the Clean Water Act prohibiting new gold mines from dumping their tailings into waterways.  Even at that time, EPA determined that most mines no longer dumped their tailings into water bodies, and that

“The plain language of the Clean Water Act simply prohibits the discharge authorized by the Corps of Engineers,” Waldo said.

The Corps’ permit granted Coeur d’Alene Mines Corporation the right to dump 210,000 gallons per day of a toxic waste slurry into the lake, despite the availability of disposal methods less damaging to the environment.

The slurry is a byproduct of a gold extraction process that blends water with crushed ore. Attorneys representing mine developers and the federal government said the slurry is legal fill material in their view of the law, but the court rejected that argument.

The mine site is in Berners Bay, about 35 miles northwest of Juneau. The disputed permit would fill Lower Slate Lake, a 23-acre wooded, sub-alpine lake in the Berners Bay watershed. All fish and most other life forms would have been killed.

Coeur already had approval to build a conventional dry land tailings disposal facility, but the company applied for a permit to dump tailings directly into the lake as a cost-cutting measure.

Earthjustice represents the Southeast Alaska Conservation Council, Lynn Canal Conservation, and the Sierra Club.

Read the decision (PDF)