In a recent letter, John Hirsh compares sediment from “pulverizing glaciers” and landslide debris to potential impacts of a mine at Glacier Creek. He concludes that because sediment from glaciers and landslides has not harmed fish runs, neither will mining.

Fortunately for fish, wildlife and people, glaciers and landslides do not target high sulfide mineral deposits the way mines do. Mining allows acid and heavy-metal-generating reactions to occur at much higher rates than occur in nature. Often, mining brings ore from thousands of feet underground to the surface, where air and water react with the minerals to create sulfuric acid. This acid then leaches heavy metals and other toxins into nearby water bodies.

I am not aware of glacial sediments or landslide debris anywhere that concentrate toxins the way tailings piles like the ones at Greens Creek Mine do. Rocks near the surface subject to landslides have been exposed to water and oxygen for centuries. Reduction of sulfide to create acid drainage would have occurred long ago. The ore body being explored by Constantine at Glacier Creek is a continuation of the deposit at Greens Creek. The Greens Creek EIS indicates that the company will need to treat their waste for hundreds of years, possibly “in perpetuity.”

I agree with John that there are many reasons to not have a mine, but unlike his conclusion, I would include threats to our salmon as one of them.

Eric Holle

Lynn Canal Conservation

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