DEQ Public Meeting in Stephenson, MI – January 9, 2019
My name is John Engel, a member of the Executive Committee of the John Muir Chapter of the Sierra Club and a retired Project Manager for a consulting engineering company.
The 632-mining permit amended environmental impact assessment Section 2.4.2 groundwater quality states: No known occurrence of contaminated groundwater on the project site was observed in the monitoring wells during the study.
Section 3.4.4 (Foth 2015b) of the environmental impact assessment describes the following mechanisms as potentially affecting groundwater quality.
- A leak in the closure tailings facility liner, cap and cover system.
A March 11, 2015 publication, Impermeable Basal Structure – With Synthetic Liners by the Geological Survey of Finland states: There is little data available about the field performance of liner materials and the lifetime prediction is usually based only on material tests of the synthetics (including high stress, aggressive fluids, and elevated temperatures), which by no means guarantee the duration of the liners service life, too often causing unsatisfied lifetime predictions. (1)
Will the tailings cap and cover system withstand the increased frequency of severe weather events without eroding or collapsing? The liner system and monitoring technology has not been verified to withstand the test of time. Tailings and waste rock are reactive, creating sulfuric acid, heavy metals when exposed to oxygen and water. The reaction will occur for hundreds of years. When the tailings facility liner fails and the backfilled mine pit waters become acidic, the groundwater will contaminate the marshes, rivers, and streams, adjacent to the mine site. (2)
The tailing management facility is 127.8 acres and approximately 148 ft high containing 4.9 million cubic meters of tailings or approximately 356,000 loads in a 18-yard dump truck. The facility will contain an additional 5.9 million cubic meters of reactive waste rock, approximately 429,000 18-yard dump truck loads.
Who is going to be held responsible and pay for the removal of the waste rock and tailings from the mine site, years after the investors have received their money and Aquila Resources have closed the mine site?
The Sierra Club is very concerned about the Back 40 Mine Project causing catastrophic long-term environmental damage. The location of the mine, processing mill, and reactive tailings storage facility, minimizes the value and fails to protect the quality of the groundwater, including the aquatic life in the Menominee and Shaky Rivers. Environmental damage will affect the states of Michigan and Wisconsin, as well as, despoiling sacred cultural sites of the original home of the Menominee Indian Nation.
Speaking on behalf of the 3.5 million members and supporters of the National Sierra Club, including 150,000 members and supporters of the Michigan Chapter, we strongly oppose risky sulfide mining operations such as the Back 40 Mine!
References:
- Impermeable basal structure – with synthetic liners
Latest update: 03.11.2015
Mine Closure: Wastes and waste facilities
Anna Tornivaara, Geological Survey of Finland, P.O. Box 1237, FI-70211 FINLAND:
Anna Tornivaara of Geological Survey of Finland, Espoo (GTK) with expertise in: Geochemistry, Geology and Hydrogeology 03.11.2015 - Flambeau Mine: Water Contamination and Selective “Alternative Facts”
Robert E. Moran, Ph.D. Michael-Moran Assoc., LLC Water Quality/Hydrogeology/Geochemistry Golden, Colorado, U.S.A. remwater@gmail.com remwater.org