ELY—With each new sample of lake and stream water, organizers with the Campaign to Save the Boundary Waters are building a database that could one day become the foundation for the permanent protection of the nation’s most-visited wilderness area from the potential threat of a sulfide-based copper-nickel mine.
It’s a long-term strategy designed to combine water quality test data with existing law to protect water quality that the state’s Pollution Control Agency has described as “immaculate,” and worthy of the highest level of protection. Becky Rom, national chair of the campaign, outlined the group’s strategy during a Tuesday Group meeting in Ely earlier this month.
The group laid the foundation for the effort several years ago, with the intent of thoroughly documenting the impact on water quality downstream of mining operations, including the current Northshore taconite mine and the former Dunka pit, both near Babbitt. Their results, compiled by trained personnel and tested at independent laboratories, have demonstrated the group’s ability to document major point sources of mining-related pollution and track the impacts of that pollution for as much as 25 miles downstream. That places the pollution at the edge of the BWCAW.
The effort has already yielded a major win with the MPCA’s decision last year to include Birch Lake on the draft list of the state’s impaired waters, due to sulfate concentrations that exceed the state’s allowable standard of 10 milligrams per liter, or mg/l, for wild rice waters. Rom, speaking to the Tuesday Group, noted that the federal Environmental Protection Agency, had also approved of that listing in May, clearing the way for Birch Lake’s impairment to be made final.
Rom said the group began its research effort by testing conductivity, which is a measure of certain ions in water that are typically connected to industrial pollution. “What we found was that there were hot spots,” Rom said. Those hot spots were at the mouth of the Dunka River and, particularly, Unnamed Creek, which flows into Birch Lake’s Bob Bay. That began a much larger and more methodical analysis that gathered thousands of samples from across Birch Lake as well as from all of its tributaries as well as tributaries to downstream waters, including the White Iron chain of lakes, all of which drain into the BWCAW.
Test results from the tributaries that were unimpacted by mining showed sulfate concentrations ranging from 0.6 mg/l to 1.6 mg/l, noted Rom. “It’s what our lakes would have been like had we not had these two mines,” she said.
By contrast, the results from Unnamed Creek, located downstream of the Dunka pit, saw concentrations of sulfate at well over 300 mg/l, while the levels at the outlet of the Dunka River run about 100 mg/l.
Unnamed Creek discharges acid rock drainage left over from sulfide-bearing overburden that was removed by LTV back in the 1960s to access a taconite deposit underneath. Toxic runoff from the site is partially mitigated by tarps covering the waste rock stockpile and a series of engineered wetlands that were built to control discharges, but the site continues to discharge effluent that exceeds state and federal water quality standards.
The Dunka River is connected to the Peter Mitchell pit, a taconite mine, which typically generates less sulfate than a sulfide ore body.
While the sulfate concentrations downstream from these two point sources are significantly diluted, elevated sulfate levels, well above the natural background, can be found more than 20 miles downstream from these locations, according to Rom. While mining only affects about 13 percent of the Birch Lake watershed, the impact on sulfate levels has been dramatic. “It has led to a 3,000 percent increase in sulfate,” said Rom.
Rom noted that the impact of that sulfate goes beyond its effects on wild rice, noting that it also plays a role in the methylation of mercury, which is the process by which less toxic forms of mercury are converted to a more toxic form that is readily absorbed and concentrated into fish tissues.
Why it matters
Building an enormous water quality database can be a powerful evidentiary footing for the campaign as it seeks to head off future sulfide mining within the upper reaches of the Rainy River watershed. Its value may become even more apparent depending on the outcome of the November election, given that Project 2025, the handbook developed by the Heritage Foundation for a second Trump term, calls for the reversal of previous decisions to terminate two key federal mineral leases for Twin Metals. That’s the company seeking to open a sulfide-based copper-nickel mine near the BWCAW.
With its federal leases gone, at least for now, Twin Metals has focused on exploration of mineral rights near Birch Lake’s Bob Bay. Depending on the outcome of that process, the campaign’s water quality test data could prove invaluable in keeping sulfide-based mining out of the watershed.
“Because Birch Lake is officially recognized as a wild rice lake impaired for sulfate, no regulatory agency can approve industrial discharge permits that cause a net increase in loading of sulfates,” said Rom.
In that sense, the campaign’s test data and the MPCA’s listing of Birch Lake as impaired for sulfate are potential shots across the bow to Twin Metals, that are likely to bolster any future legal or regulatory challenges to a potential mine, which would almost certainly increase sulfate discharges into Birch Lake.
Rom said the state of Minnesota may also prove a bulwark against a Twin Metals mine, and that’s another way that the campaign’s hard science can play a key role. The campaign is currently citing its findings in its push to convince the state to update its mining rules to be more protective of water quality. According to Rom, the data makes the case. “By allowing mining in the headwaters of the Boundary Waters, Minnesota rules are inadequate to protect the Boundary Waters from pollution and impairment,” she said.