Several previous blogs described our community resisting, due to the vague plans and potential harmful impacts to our health and economy, a proposed hyperscale data center. We felt happy to achieve a one-year moratorium on all applications submitted to our town.
At the last meeting of our group called ProtectWakeCountyCoalition, I learned about an organization called FAIME.org for experts to register and offer environmental support for non-profit groups. Once I became accepted, they connected me with a group called Protect the Porkies to help them evaluate potential impacts from copper-silver mining next to the Porcupine Mountains State Park and Lake Superior. The specific task is to review the NPDES permit and prepare comments to the State of Michigan’s Department of Environment, Great Lakes and Energy known as EGLE.
I spent the past two weeks and about 25 hours so far on the task to review documents and prepare comments that I plan to submit to EGLE. I’m posting these comments here and if you feel inclined to take action, please follow the Protect the Porkies website.
The Plan
A Canadian mining company operating in the Upper Peninsula of Michigan proposes to construct underground mine shafts sloping towards Lake Superior reaching within 100 feet. The source of water to be used for mining is uncertain and may require a pipeline to extract water from Lake Superior. Mined rock removed by slurry sends ore grade metals including copper and silver that are concentrated by several water treatment methods. Waste rock tailings would be impounded on land next to Porcupine Mountains State Park and fluids are discharged to a creek containing critical habitat for endangered species.
The company is requesting MI EGLE via a NPDES permit application to allow discharge of up to 0.504 million gallons per day (184 million gallons per year) of contaminated wastewater, toxic metals, storm water, and demineralized reverse osmosis fluids which must be ‘within limits’ to pollute the West Branch of Namebinag Creek that flows back towards Lake Superior. Expanded electrical grid transmission and onsite power requirements will be significant to operate mining operations including reverse osmosis systems and likely would necessitate additional capacity from baseload power consisting of burning coal, natural gas turbines, or nuclear including small modular reactors that will also require significant water resources and other impacts including air pollution and additional waste disposal.
A total complete plan for the entire operation is needed to properly assess the mining permit requirements including for the NPDES permit. With the availability of a complete plan, options for zero liquid discharge could be implemented that would prevent contaminant discharge making the NPDES permit unnecessary.
Consequences of Accepting the Proposed Copperwood NPDES permit
Natural processes will be altered by mining that could also impact operations. The 50-foot cliff bank at Lake Superior is eroding towards the mine site at the rate of 1.6 ft/year so within about 62 years the lake shore could reach the proximity of the proposed underground mine if built as proposed within 100 feet of the banks of Lake Superior.
The process of mining copper sulfide introduces oxygen and water which can produce sulfuric acid creating acid mine drainage. Sulfide can also oxidize into sulfate which releases toxic metals including arsenic, chromium, lead, molybdenum, selenium and strontium. Groundwater becomes contaminated that is not collected by mining operations which impacts the environment.
The 2018 Highland Copper Feasibility study states on Page 8-1:
“Mineralization: Chalcocite and other Cu2S-CuS minerals + bornite are diagnostic; typical minerals hematite–chalcocite–bornite–chalcopyrite–pyrite; may be zoned with chalcocite-bornite central, chalcopyrite-pyrite medial, galena-sphalerite peripheral; finely disseminated; copper sulfides replace framboidal or colloform pyrite; and, carbon-rich materials in favorable host rocks but usually consumed by redox reactions during copper mineralization processes.”
The discharge of heavy metals into the creek possesses numerous detrimental impacts. The presence of significant iron sulfide minerals when exposed to oxygen and water can create sulfuric acid and result in acid mine drainage. Iron also can act like a sponge for metal sorption. Dissolved metals forming soluble complexes can pose a long-term threat through sorption on clay minerals and iron and manganese oxyhydroxides.
The NPDES permit requests Michigan’s permission to dump an average of 2,100 pounds per day for ten months allowing for short term spikes up to 3,200 pounds per day. For two months in the spring, releasing an average of 2,300 pounds per month with spikes up to 3,500 pounds per day is being requested.
Annual totals of total dissolved solids (TDS) proposed to be released into the creek:
TDS (2,100 lbs/day * 30 days * 10 months) + (2,300 * 30 days * 2 months) =
768,000 pounds/year based on maximum flow rate allowed!
Up to about 768,000 pounds/year of dissolved solids could be released into the creek. Much of these dissolved solids may not stay dissolved and become solids through processes of mineral precipitation, ion exchange and sorption. The annual weight of solids is equivalent to the weight of 153 Ford F-150 5,000 pound trucks.
Imagine the contamination of the watershed while mining occurs over 10+ years. Furthermore, with the creation of a tailings dam impoundment, leaching and discharge of metals will occur long after the mining ceases.
The NPDES permits states that reverse osmosis (RO) treated water “must be managed such that effluent hardness will not produce toxic metal effects in the effluent discharged to West Branch Namebinag Creek. The permeate from RI is demineralized and can have corrosive properties due to the absence of ions. The permittee must manage the permeate effluent discharge to minimize toxicity in conjunction with whole effluent toxicity testing.”
Hardness is not currently on the parameter list which is a test for dissolved calcium and magnesium which is important to quantify for preventing leaching of metals and buffering acid mine drainage.
However, the NPDES permit required toxicity tests on flathead minnows and fleas does not consider impacts to macroinvertebrates and other aquatic organisms. As creek levels rise and fall with weather events, seasons and variable mining discharge quantities, water stored in banks and evaporated water containing toxic heavy metals and stream sediments are washed onto land and can become airborne and dispersed into the streams and forest. Bioaccumulation occurs throughout the food chain impacting wildlife.
The list of parameters proposed to be monitored in the NPDES permit is incomplete and more information is required to monitor geochemical impacts to the environment and should also include aluminum, alkalinity, chloride, hardness, iron, radium, nitrate, nitrite, sodium, sulfide, sulfate, and uranium.
The permit should not allow for reduction in frequency from weekly to monthly monitoring after 12 months for 20 elements.
In July, 2009, on behalf of the mining company’s consultant AECOM authorized Fishbeck, Thompson, Carr & Huber, Inc. (FTC&H) to perform baseline aquatic studies including fish, macroinvertebrates and physical habitat. The report is: Baseline Fisheries, Macroinvertebrate and Physical Habitat Studies for the Copperwood Project 2010.
From Executive Summary:
“All streams within the project area are regulated pursuant to Part 301, Inland Lake and Streams, of the Natural Resources and Environmental Protection Act (NREPA), 1994 P.A. 451, as amended. However, from the perspective of providing quality stream habitats for fish and macroinvertebrates, all streams suffer from varying degrees of environmental degradation. Despite the lack of fish in the upper reaches, and the presence of degraded water in the beaver ponds, the highest quality streams are Unnamed and Namebinag Creeks. The presence of redside dace in their lower reaches makes the protection of their watersheds and instream habitats critical.”
On Page 21 the report states: “Populations of reside dace within the Copperwood site should be protected from human-related impacts. The Namebinag and Unnamed Creek watersheds should be delineated and project activities within these watersheds, especially those that could alter hydrology, water temperature or turbidity, should be avoided or minimized to the extent possible. Road crossings or other earth-disturbing activities within these watersheds should incorporate appropriate best management practices to eliminate impacts to these streams.”
Why is the mining company ignoring their consultant’s directions?
The Highland Copper 2018 Feasibility Study, Page 6-4 states, “An environmental geochemical examination was completed on eight reject samples of mineralization, hanging wall, and footwall rocks from three historical drill holes. Interpretation of the geochemical test results by Geochimica, Inc. indicates that Copperwood rocks are unlikely to be acid generating and, consequently, may be characterized as non-reactive under Michigan mining laws. In addition, the rock pile created by the extraction of copper-bearing rock from the underground exploration activity in the 1950s was trenched and sampled after being subjected to approximately 50 years of wet, oxidizing conditions. Based on visual observations, the rocks appear to be non-reactive.”
I reviewed the following article and find the above statements to be exaggerated and potentially misleading:
Theodore J. Bornhorst and Mark J. Logsdon, 2016. Predicting Future Water-Quality Impacts from Mining: a 52-yearold Field Analog for Humidity-Cell Testing, Copperwood Deposit, Michigan. Economic Geology, vol. 111, pp. 527-542.
The article is very useful for comparing predications of water quality from lab column tests with a prior mining rock pile that already had been significantly altered. I do not believe this brief study in 2016 is representative of all “Copperwood rocks” by using simplified modeling and does not conclude there is no potential for acid mine drainage. In fact, they recommended longer term studies would be needed but were not continued. This study is not comparable to impacts that could occur from the NPDES discharge on the creek and surrounding environment. Therefore, the Copperwood Resources Inc. feasibility study discussion of acid mine drainage is insufficient and must be reevaluated.
Opportunity to Prevent Pollution by Denying the NPDES application
Given the skyrocketing commodity prices of copper and silver, we urge MI EGLE to require Copperwood mining to be a zero discharge facility by fully using the water treatment plant to concentrate and remove all liquid contaminants including RO process water. Instead of accepting the current proposal, we advocate rejecting the NPDES permit and require Zero Liquid Discharge (ZLD). Here is a 2026 article by Minetek.com comparing ZLD with conventional methods.
Don’t let the state park and banks of Lake Superior become a toxic waste dumpsite!
Granting a National Pollutant Discharge Elimination System “NPDES” permit to the mining company defeats the intended purpose of eliminating pollution discharge and enables pollution into an unpolluted, relatively pristine environment. The permit would allow significant pollution to occur endangering critical habitats with potential negative effects on an endangered species of fish native to the area - the Redside Dace.
A tailings management facility can be located much further away from the mining site and not located next to the state park.
Protect the Porkies issued a Press Release with the following statements of mine:
To better understand potential harms of the current wastewater discharge proposal, Protect the Porkies contracted Bill Dam, a consultant who has worked with the Department of Energy and the U.S. Geological Survey. “The total weight of the dissolved solids entering the creek would amount to up to 768,000 pounds per year,” Dam said. “This is the equivalent of 153 Ford F-150 trucks crashing and dissolving into the creek, every year, directly upstream from an endangered fish and Lake Superior.”
Instead of discharging into the stream, both Dam and Grotewohl are calling upon the company to utilize a Zero Liquid Discharge (ZLD) system, in which all wastewater is mechanically evaporated, and the remaining solids are taken off-site.
“Given the skyrocketing commodity prices of copper and silver, the mining company can afford to implement feasible alternatives that will be significantly less harmful to the area and its lifeforms,” Dam said.