Idaho Copper, a new “shell company” for the Canadian mining company MultiMet, is proposing to construct over 8 miles of new roads and clear 122 drill pads in the Boise River headwaters near Grimes Creek for a mining exploration project. The company hopes that the CuMo 2023 Exploration Project will lead to development of one of the largest open-pit copper and molybdenum mines in the world.

Both exploration and mine development for the CuMo project are extremely controversial. The exploration site is upstream of half of Idaho’s population, and the Boise River is the lifeblood of the Treasure Valley. The Boise River watershed provides approximately 30 percent of Boise’s drinking water supply and over 300,000 acres of farmland. This endeavor places the Boise River watershed at unacceptable risk.

We Are the Boise River from Idaho Conservation League on Vimeo.

This isn’t the first time a variation of this project has been proposed. The U.S. District Court has put the 2011 and 2015 exploration projects on hold twice because the Forest Service failed to adequately assess the project’s impacts on groundwater and rare plants. 

Our Concerns With the Project

We need to ensure that the Boise River watershed – the source of many Idahoans’ drinking water – is protected. Even exploration activities can have negative impacts. Transportation of diesel fuel on narrow riverside roads, new road construction, and 24/7 drilling operations could have negative effects on water quality, recreation, public safety and wildlife.The Forest Service also needs to take a closer look at how surrounding communities and recreationists will be affected by increased dust, noise and traffic and exploration activities.

ICL is also concerned about the potential of this exploration project being used as a springboard to eventually construct one of the world’s largest open-pit copper and molybdenum mines in the Boise River headwaters. If the exploration proceeds and an open-pit mine is eventually developed, it would create over 1 billion tons of mine tailing waste. Poorly engineered and managed tailings storage facilities have failed with catastrophic consequences – the tailings dam collapse from a modern, state-of-the-art mine in Brazil a few years ago gives us pause and raises concerns about open-pit mine development upstream of communities. Air and water pollution from poorly managed open-pit mining operations can extend for hundreds of miles. And according to the U.S. Environmental Protection Agency, mining is already the number one toxic polluter in the United States.

Under the Mining Law of 1872, the Forest Service cannot deny mineral exploration or development, but they are required to prevent, minimize, mitigate and repair adverse environmental impacts. We need our members and supporters to speak up again for the Boise River headwaters.

ICL and our partners at Idaho Rivers United, Golden Eagle Audubon and the Sierra Club are hosting a webinar on Tuesday Oct. 24 at 7 pm about the potential impacts of mining and how to write effective comment letters. Learn more about and register for the webinar here.

You can also speak up for the Boise River today by taking action below – and submitting public comments on the project!