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Kensington Mine Project

Aerial photos of Lower Slate Lake before and after the Kensington Gold Mine's dumping of mining waste.

Aerial photos of Lower Slate Lake before (top photo) and after (bottom photo) the Kensington Gold Mine's dumping of mining waste.

Top photo courtesy of Irene Alexakos; Bottom photo courtesy of Alaska DEC

Case Overview

In issuing a permit for a gold mine, the Army Corps of Engineers considered the mine’s chemically processed, toxic mine waste to be “fill material” under the Clean Water Act, bypassing strict EPA limits for this type of pollution. As a result, millions of tons of mine waste will be dumped into a pristine sub-alpine lake in Southeast Alaska, killing all fish and aquatic life in the lake.

In March 2007, the Ninth Circuit Court of Appeal announced that the permit to allow the mine waste to be dumped in the lake was illegal and would be struck down. On October 29, 2007, the same court—in this case, all 27 active judges—refused to reconsider the decision made in March.

In a 6–3 decision on June 22, 2009, the U.S. Supreme Court reversed the decision of the Ninth Circuit Court of Appeal. The mine is now operating and dumping its waste in the lake, but Earthjustice and others are working to change agency rules to avoid this result in the future.

Related Features

A Dangerous Precedent for Other Mines and Other Industries

The Supreme Court's decision in the Kensington Mine case will have impacts well beyond Alaska's remote Lower Slate Lake. Any industrial facilities with significant components of solids in their wastewater—and there are many—will now be able to potentially dump their waste into nearby lakes, rivers or streams.

Case Updates

January 12, 2009 | Blog Post

Earthjustice Defends Nation's Waterways at Supreme Court

Earthjustice press secretary Raviya Ismail was at today’s (Jan. 12) U.S. Supreme Court hearing on whether the Clean Water Act allows Coeur Alaska’s Kensington Mine to fill Lower Slate Lake in Alaska with mining waste – killing all aquatic life. Earthjustice attorney Tom Waldo argued to protect the lake. The high court decision, expected by June, could determine whether waterways throughout the nation may be likewise filled and killed. Here is Raviya’s report:

January 6, 2009 | Map

Lower Slate Lake

Map showing the proximity of Lower Slate Lake to Juneau, Alaska

December 19, 2008 | Legal Document

Kensington CWA Merits SCOTUS

Argument that Kensington Mine, AK waste should not be classified as fill and violates the Clean Water Act.