8. St. Louis River

The St. Louis River is threatened by new copper-nickel sulfide mining in its headwaters that would destroy or degrade thousands of square miles of pristine forested wetlands and streams.

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Photo credit: Lori Andresen

Location: Minnesota

Minnesota’s Arrowhead region is known for its pure and abundant waters, deep forests, expansive wetlands, and recreational opportunities. However, a proposed copper-nickel sulfide mine at the headwaters of the St. Louis River, the region’s main artery, threatens drinking water, wildlife, and the treaty-protected hunting, fishing, and gathering rights of the Ojibwe people. It is critical that state and federal regulators deny permits for the mine plan because it does not sufficiently protect the St. Louis River and its communities.

The River

The largest U.S. tributary to Lake Superior and the entire Great Lakes system, the St. Louis River is 194 miles long and drains 3,634 square miles of Minnesota’s northern forests and wetlands. It begins in the Laurentian Uplands, where small streams divide in three directions towards Hudson Bay, Lake Superior, and the Mississippi River. This is a land that harbors timber wolves, moose, and Canada lynx, along with wood turtles, sturgeon, and 163 species of breeding birds.

The St. Louis watershed is a prolific source of wild rice, the “food that grows on water,” which led the Ojibwe people to settle in the region. The river remains the primary reservation fishery for the Fond du Lac Band of Lake Superior Chippewa. The mainstem of the St. Louis River and several of its larger tributaries have been dammed for hydropower generation, disrupting connectivity and increasing mercury bioaccumulation in fish.

After the river leaves the reservation, it flows through the magnificent Jay Cooke State Park and into a rare freshwater estuary between the Twin Ports of Duluth, Minnesota, and Superior, Wisconsin. Historically, the estuary was heavily impacted by industry, resulting in its designation as a Great Lakes Area of Concern, and still hosts the busiest port on the Great Lakes. However, an investment of more than $1 billion and a commitment to restoration and economic development by the City of Duluth has the lower St. Louis well on its way to recovery.

The Threat

The St. Louis River is threatened by new copper-nickel sulfide mining in its headwaters that would destroy or degrade thousands of square miles of pristine forested wetlands and streams. The first of the new mining proposals, PolyMet Mining’s NorthMet Project, would destroy 1,000 acres of wetlands, and indirectly impact thousands more wetland acres. It would also require a complex federal land exchange resulting in the turnover of more than 6,000 acres of biologically rich lands from the Superior National Forest and the St. Louis River watershed to mining companies.

The St. Louis River and its tributaries have already been adversely impacted by more than a century of iron mining, with the loss of thousands of acres of headwaters wetlands and streams. However, this new type of mining is likely to be more damaging to the environment because the copper and nickel are bound up in sulfide-bearing rock, the mining of which commonly results in acid drainage and increases heavy metals and sulfates in downstream waters. Increased sulfate degrades wild rice stands and contributes to the methylation of mercury, which is already present in St. Louis River fish at levels that threaten public health. A 2013 study by the Minnesota Department of Health found that 1 in 10 infants on the North Shore of Lake Superior are born with unsafe levels of mercury in their blood, potentially impairing normal development.

A mining proponent called PolyMet “the snowplow” for the industry, clearing the way for many sulfide mines to follow. In addition to the cumulative effects of pollution and wetlands loss by an expansion of hard rock mining in the headwaters, the tailings basins and water treatment plants for PolyMet and other mines would need to function flawlessly for centuries. The long-term persistence of this threat multiplies the potential for ruptures of the tailings basin and mine pit from increasingly severe storm events related to climate change— threatening the river, its wildlife, and its people for many generations to come.

What Must Be Done

In a public comment period for the PolyMet Mining Project and Land Exchange Supplemental Draft Environmental Impact Statement (EIS) last year, permitting agencies received 58,000 comments— almost all of them opposing the mine. The Minnesota Department of Natural Resources, U.S. Army Corps of Engineers, and U.S. Forest Service plan to release the Final EIS for the PolyMet Mine in Spring 2015, followed shortly by draft permits and a Forest Service decision on the proposed land exchange. The agencies must listen to the public and refuse to permit the new mine or allow the land exchange, because the mine would pollute the St. Louis River watershed and the land exchange does not protect the interests of the tribes or the environment.

How You Can Help

We are expecting an Environmental Impact Statement to come out for public comment later this year. Sign up to be notified when it's time to take action.

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