Huge 'Wall of Water' Could Devastate Great Lake

The clock is ticking in a legal battle over a Minnesota mining project that campaigners warn could inflict catastrophic damage on Lake Superior and nearby communities.

The Minnesota Court of Appeals is deliberating whether a new Environmental Impact Statement (EIS) is required for the Mile Post 7 West Ridge Railroad Relocation, Dam Extensions and Stream Mitigation Project in Lake County.

Environmental advocates argue that the risks posed by the project's tailings dams could have dire consequences for the Great Lakes ecosystem and residents living downhill.

At the heart of the case is the Mile Post 7 tailings basin, which holds a slurry of crushed rock, wastewater and other remnants of taconite mining.

Tailings contain toxic materials, including trace metals, cyanide and sulfuric acid, making safe containment crucial.

However, critics warn that the tailings dams' nearly 50-year-old design is no match for modern environmental challenges like climate change, which increases the risk of extreme rainfall and flooding.

"Designing a tailings dam where a failure is going to result in a collapse that will spew toxic waste into Lake Superior and could lead to a toxic mudslide into the homes and businesses of two towns makes no sense according to modern science and evidence," Paula Maccabee, an attorney for WaterLegacy, told Newsweek.

Wild stormy waves on the rocky shore of Lake Superior along Autumn forest. If the mine tailings basin at Mile Post 7 were to fail, it would be catastrophic for this ecosystem. Susan Rydberg/Getty

Maccabee argued before the court on November 13 that the current project should not proceed without a new EIS.

Court briefings submitted by Maccabee revealed that the original 1976 EIS warned of catastrophic consequences if the site failed.

It projected that a breach of South Dam 1 could unleash a "28-foot-high wall of water," traveling at "more than 20 miles per hour," ravaging the Beaver River Valley and eventually spilling into Lake Superior.

The Mile Post 7 basin was constructed in the late 1970s after the now-defunct Reserve Mining company settled with the U.S. Environmental Protection Agency over environmental violations.

Even then, the site was deemed risky. The original EIS recommended an alternative location for tailings disposal, warning that Mile Post 7 was unsuitable because a dam failure would "thwart the entire purpose of on-land disposal by emptying stored tailings into Lake Superior."

Now owned by Ohio-based Cleveland-Cliffs, the facility's tailings basin has grown significantly since its original approval. The company has requested to extend the storage dams further, a move the Minnesota Department of Natural Resources (DNR) claims does not constitute an expansion under existing permits.

Cleveland-Cliffs did not respond to a request for comment from Newsweek.

The DNR defends its decision not to require a new EIS, asserting that the dams meet all current safety standards and are among the most closely monitored in the state.

Gail Nosek, the DNR's communications director, told Newsweek that the project is subject to rigorous inspections and ongoing regulatory oversight. She also noted that the most recent dam breach analysis was completed in 2022.

"The Mile Post 7 tailings dams are some of the most closely regulated dams in the state, meeting all applicable factors of safety and state dam safety laws," she said.

Critics, however, are not convinced. WaterLegacy argues that key safety data provided by the DNR has been heavily redacted, undermining transparency.

Maccabee also pointed to new science showing that even properly constructed dams are at higher risk of failure than was once thought.

"New science shows that over a period of 100 years, the statistical chance of dam failure approaches 50 percent and over the long term, it approaches 100 percent," Maccabee said.

Environmentalists stress that the risks associated with tailings basins like Mile Post 7 do not end when mining operations cease. The waste stored in such facilities remains a long-term hazard, posing perpetual risks to nearby water resources.

Maccabee added, "This storage is forever, and there are all kinds of ways in which it can fail."

Should the dams fail, the toxic wall of water could destroy ecosystems, impair drinking water supplies and devastate the Lake Superior region, which holds 10 percent of the world's freshwater.

The Minnesota Court of Appeals is expected to rule within 90 days. If it finds in favor of WaterLegacy, a new EIS would be required, potentially delaying the project and prompting a reassessment of the risks.

This decision will determine whether current safety measures are sufficient or whether the half-century-old disaster warning is more relevant than ever.

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