State legislators have spent the past two years debating an iron ore mining bill. As Wisconsin Public Radio's Shawn Johnson reports, there are reasons it's never been mined before.

The debate is over a bill aimed at clearing the way for a massive open pit iron mine in Northern Wisconsin. It's a long time by legislative standards, but the ore body they're fighting over is more than a billion years old.

If this mine ever happens it would carve a miles long, nearly one-thousand foot deep hole in the Penokee Hills of Iron and Ashland Counties. When a group of state lawmakers recently toured the area they wanted to see where the mine would be. But first Cyrus Hester wanted to show them a mockup on a dining room table.

"Alright, we put some tailings there. This isn't a mining engineering plan. We'll put some waste rock that's been blasted up."

Standing in for mining "tailings" and "waste rock" in this example are sugar and crushed up crackers. Hester piles them on a plate--in this example it's a liner designed to separate the waste rock from the ground. Then comes the "rain." Hester pours a pitcher of water over the top of the plate.

"And eventually it over-tops right."

Sugar water and soggy crackers are everywhere. By now Hester has the entire room's attention. His point, he says, is that sometimes, engineering fails.

"We have to bring with this a lot of humility. And engineers and economists are beautiful because they believe in the potential of the human species. But ecologists and some of the natural resource scientists are a little more cynical. Because we have a lot of history that says we can't always fix our ways out of these things."

As an environmental specialist for the Bad River Band of Lake Superior Chippewa, Hester is very skeptical that a mine of this scale can work. And tribal leaders are fearful it will destroy a delicate watershed that's been the very foundation of the tribe's way of life.

To understand why, you have to understand the rock, says Northland College Geology Professor Tom Fitz.

"This is the Ironwood iron formation right here. And as you can see, it makes up the backbone of the Penokees."

Backbone is an apt description. This is not an ore body that rests flat. You can't mine it by just skimming off the surface. Think of it instead as standing more upright. Fitz says the iron ore is what's holding up the Penokee Hills. To get at it, you have to dig a pit that's deep and wide.

This worries some members of a local mining impact committee, like Bud Benter, Chairman of the tiny town of Anderson in Iron County.

"It'll never, ever, ever be the same. This is not the day of the hole in the ground where they went to work with a pick and a shovel and a light on their head."

But others like Iron County Clerk Michael Saari told that same group of legislators that the region is comfortable with mining.

"I realize what you guys are trying to do with the environment, and I agree with that. But you need to get a bill done, and we need to get this passed some way."

This is where engineering comes in. A hole this big means millions of tons of waste rock that has to go somewhere. If the rock surrounding the iron ore has traces of sulfides in it--and Professor Fitz says it does--it's even more challenging. Because sulfides exposed to water can lead to acid mine drainage.

The mining company GTAC had a permit to take samples of the rock but gave the permit back and kept what data it has collected private. GTAC President Bill Williams says the mining bill needs to pass first, otherwise taking more samples is a waste of money.

"The question is why invest into a project that you don't know if you have a chance at even opening. You're spending one to two million dollars and if it says you can't mine in Wisconsin, then you've just thrown two million dollars down the toilet."

Williams says there are all sorts of ways to treat water if sulfides are found. But Cyrus Hester with the Bad River says he's not satisfied with what he's hearing.

"And there's kind of some folks saying 'behind this curtain, things look very different.' But science does not rely on faith, we rely on observation."

In Wisconsin, regulators at the Department of Natural Resources would ultimately evaluate that science. And that's where the mining bill comes in. It would give the Department less discretion to deny a permit for one of the largest taconite mines in North America.

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