Thanks to everyone who came out to Idaho Brewing Company in Idaho Falls last week to hear about proposed mining projects in the area. For people who couldn’t make it or who want additional information, here is more on the Kilgore gold exploration project.

The Importance of Migration Corridors

When it comes to finding "charismatic megafauna" like grizzly bears, most folks think of places like Yellowstone National Park or Glacier National Park. But over the years, we’ve learned that protecting core areas alone is not enough. For wildlife populations to remain viable far into the future, we also need to maintain the corridors connecting core areas and make sure individuals can move between them. In addition to grizzly bears, this is true for forest carnivores like lynx and wolverine as well as for big game like bighorn sheep. The Centennial Mountain range on the Idaho-Montana border provides a key linkage between Yellowstone National Park and the Beaverhead and Bitterroot mountains.

Exploring for Gold

The Centennials are also on the edge of a number of calderas, the remnants of explosive volcanic blasts that left behind a pattern of concentric faults in the bedrock. Groundwater seeped into these faults, became superheated by the volcanic activity, and dissolved gold from the surrounding rocks before depositing it closer to the surface along those fault lines.

A Canadian mining company, Otis Gold, has been exploring a portion of the Centennial Mountains on the Caribou-Targhee National Forest over the last several years. Previous operations in the Kilgore Project area ┬áhave been relatively small scale. I had a chance to tour the area twice and found the U.S. Forest Service staff and Otis Gold staff to be open and transparent. To Otis Gold’s credit, after a series of discussions with ICL, the company shifted past operations and took additional steps to minimize and mitigate impacts.

Now the company hopes to expand operations, construct over 10 miles of temporary road and clear up to 140 drill pads over a five-year period. Three drill rigs would operate 24 hours a day from mid-June to the end of November. While some animals become desensitized to industrial disturbances, others do not. Exploration activities as proposed could affect animal movements through the area. Plus drilling would expand into two new drainages and potentially affect surface or groundwater resources there.

Based on what this next round of exploration reveals, Otis Gold has said that the deposit is amenable to cyanide heap leach mining. An exploration summary stated that "there are no impediments to permitting an open-pit heap leach operation." A technical report goes on to lay out future potential for the site: "The area features potential sites for processing plant, water storage, heap leach pads and facilities."

Ironically, open-pit cyanide heap leach mining is banned just a few miles to the north in the state of Montana after a series of accidents poisoned wells and left taxpayers with enormous cleanup costs.

The Forest Service Needs to Hear from You

The Forest Service is taking comments through Friday, Feb. 9, on what issues should be included in the scope of its environmental analysis. We are asking for folks who know the area or care about bears, big game and water quality to submit comments to the Forest Service, urging the agency to implement additional measures to avoid, reduce and mitigate impacts to wildlife and water quality.

These additional measures could include concentrating drilling activities in one area at a time, reclaiming exploration roads as operations proceed instead of waiting until the end, and establishing a solid baseline of groundwater and surface water studies before allowing drilling in new drainages.

Later this spring, the Forest Service will release a draft environmental assessment for additional public comment. While it’s possible to mitigate for small exploration projects like previous activities, it is harder to mitigate for larger exploration projects such as this one. And there’s no way to mitigate away an open-pit cyanide heap leach mine in this sensitive location, if it comes to that.