Alpine lakes at heart of Kensington plan

Posted: Sunday, October 31, 2004

SLATE LAKES - The surface of Lower Slate Lake is dark and glassy, reflecting the snowbound majesty of Lionshead Mountain.

Lurking somewhere beneath are Dolly Varden and their main prey, a small minnow aptly named threespine stickleback.

The lake's fish face a potentially dramatic future.

Coeur Alaska hopes to discharge tailings from its proposed Kensington gold mine into this subalpine lake. Tailings are the crushed rock that results from mining. Within a few months, the mining venture is likely to get its answer from federal regulators.

On a recent clear day, Coeur consultant Ed Klein waded into a stream at Upper Slate Lake and scooped out a handful of the well-sorted gravel that signifies healthy habitat for these fish.

For the past four years, Klein has investigated Upper and Lower Slate Lakes, assessing the potential effect of Kensington tailings on the lower lake's small Dolly Varden population.

A short helicopter ride later, Klein sloshed into a stream feeding Lower Slate Late and gestured toward its sediment-clogged streambed.

Klein has made a few links between information he has gathered about Kensington tailings and his observations at the two lakes, which are themselves linked by a cascading creek.

• The tailings (waste rock) from the Kensington mine are not loaded with toxic metals.

• Klein's previous aquatic toxicology experiments with Kensington tailings and marine organisms show that aquatic creatures can build habitat and reside in the tailings.

• The upper lake supports spawning and the lower lake doesn't. Klein has watched Dolly Varden attempt to spawn in the sandy bed of the lower lake, but they didn't have enough oxygen to survive.

• A shallower Lower Slate Lake could improve fish habitat.

Though his conclusion is repulsive to many Juneau environmentalists, Klein agrees with Coeur Alaska that its proposed gold mine can dump its tailings in the lake - making it shallower but also raising the surface by 90 feet - and reclaim it for fish afterward.

Coeur Alaska plans to build a dam on the lower end of the lake, and Dolly Varden are not expected to survive the 10 to 15 years of tailings disposal.

The option of dumping tailings in a natural lake is usually off-limits under the federal Clean Water Act. But Coeur Alaska was able to get congressional approval to classify its tailings as "fill" instead of conventional mine tailings.

The Southeast Alaska Conservation Council has termed the legislation approving the dumping a "horrible precedent" and contrary to the primary goal of the Clean Water Act, which is to eliminate pollution discharges to U.S. water bodies.

"I can't believe they think they can take a pristine lake, fill it with waste and call it better. It's just fine the way it is," said John Hudson of Friends of Berners Bay. "If the mining industry has to come up with that much waste, they should be putting it somewhere else."

Klein said the upper lake can be used as a model to refine the company's restoration plan for the lower lake.

"The plan is to have no impact on the upper lake," he said, adding that it is "very productive" and contains 50 percent more Dolly Varden per acre than the lower lake. Those fish would have a new bypass around the lower lake to the sea.

Though the mine's water permits remain under review, state and federal regulators have said they feel comfortable with Coeur's plan to restore fish to Lower Slate Lake when the mine is closed.

The major issues left to be resolved are the mine's potential effects in Berners Bay, said Carl Shrader, a habitat biologist for the Alaska Department of Natural Resources.

In contrast to the lively debate over Slate Lakes and the mine's proposed permits, scientific surveys in Berners Bay continued quietly throughout 2003.

In March, scientists at the National Marine Fisheries Service's Auke Bay lab began collecting samples of petroleum compounds in an effort to establish a baseline for pollution in the bay. They also monitored kelp and eel grass throughout Berners Bay.

"If we had been smarter 30 years ago, we would have done this in Auke Bay," said the lab's habitat program manager, Jeep Rice. "We aren't trying to stop (the mine) or aid it. We just wanted to get out on the front end and understand the consequences."

Herring are "really, really vulnerable" to fuel pollution, said Jon Kurland, assistant regional administrator for NMFS habitat conservation division.

The Auke Bay lab has advanced overall scientific knowledge about the effects of petroleum on aquatic life because of its work on the Exxon Valdez oil spill, he said.

The NFMS regional staff has filed opposition to the mine's proposed use of Cascade Point for a ferry terminal and suggested using Echo Cove instead, he said. Kurland cited the Clean Water Act, saying Echo Cove would be the "least environmentally damaging" location.

But John Leeds, a Juneau field officer for the U.S. Army Corps of Engineers, which is considering a permit for Cascade Point, said he didn't think Echo Cove would be any less controversial with local residents.

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