The cab of Bill Heart’s Ford Ranger is cluttered with pamphlets and fishing gear, and as we pull out onto Highway 77, just north of the high ridge formed by Wisconsin’s Penokee Hills, a warm August wind rushes through the open windows and whips up patches of fur left behind by his pack of dogs. “My wife has a habit of collecting strays,” he quips. It’s summer and Heart would rather be out fishing. Instead, he is taking me to Harvest Camp, an ad hoc village of makeshift tents, wigwams-in-progress, fire pits, and a sweat lodge that has been established by the Lac Courte Oreilles tribe, one of six bands of the Lake Superior Chippewa.

Usually, harvest camps are simply a meeting place for tribal members to share their knowledge of local plant life and its medicinal applications on land they ceded through treaties, but on which they still retain hunting, fishing, and gathering rights. This camp is different. It has become a de facto base camp for protestors – people from both within and outside the tribes – who want to block a massive, $1.5 billion-open pit iron ore mine nearby.

The Penokee Hills span Iron and Ashland Counties in Wisconsin’s iconic Northwoods. The hills are the headwaters of the Bad River that flows into Lake Superior, which by surface area is the world’s largest freshwater lake. But there’s also an estimated 3.7 billion tons of iron ore underneath the mountain ridge. In total, the deposit is roughly 20 percent of all remaining US iron ore reserves. Gogebic Taconite (GTac), a subsidiary of the Cline Group, owned by Florida coal magnate Chris Cline, has its sights set on this iron ore. Mining the ore body would start with a mine roughly 4 miles in length and 800 feet deep, making it the largest open pit mine of its kind in the world. The full ore body is 22 miles long, so the long-term potential for changing the landscape is astounding. If the vein were to be completely dug out, the hole in the ground would be big enough to contain the largest open pit iron mine in the US five times over.

Heart is secretary-treasurer of the Penokee Hills Education Project, and that puts him at the frontlines of a big battle pitting Native Americans and other environmentalists against mining companies and their political allies. As the Wisconsin representative of Trout Unlimited’s national leadership council, Heart is well-versed in river hydrology and fisheries, and says the proposed mine would be an ecological disaster for a region that is defined by its water bodies.

“I’ve spent so much time trout fishing and exploring the Penokees, it is so obvious that this mining project would have huge impact on the coldwater resources of this headwater region,” Heart says. “There are hundreds of acres of intact wetlands, which produce plenty of cold water to make it possible to have a healthy brook trout population. A mine will destroy these crucial wetlands.”