Two scientists claim they have found high levels of asbestos in rock samples, at one of Gogebic Taconite's testing sites in northern Wisconsin.
Opponents of the proposed mine are sharing the findings, in hopes they prompt the state to halt the project.
The DNR says it does not yet know the extent of the mineral in the rock but expects the mining company to provide that information, along with any plan it might need to prevent potential dangers.
When asbestos fibers are released into the air, particularly certain types, they can cause fatal lung damage in those who inhale them.
UW-Madison Geochemist Joseph Skulan and Northland College Geologist Tom Fitz say the asbestos they have identified at the site, is the most dangerous type.
Gogebic Taconite has applied for a state permit to remove tons of rock from the location, for testing. In a report to the DNR earlier this year, the company stated that it did not expect to detect asbestos.
"NR 445 (DNR code: Control of Hazardous Pollutants) does not apply to the proposed bulk sampling activities because asbestiform minerals are not likely to be present in the Gogebic Iron Range near Mellen, WI. There are documented occurrences of amphibole minerals in the geology of this area but not all amphibole minerals are asbestiform minerals or asbestos. Based on our due diligence, the geologic conditions in the Gogebic Iron Range do not support the formation of asbestos."
The company is interested in extracting iron ore from the Penokee Hills, just south of Lake Superior, promising a mine would bring hundreds of good-paying jobs to the region for decades.