GRAND RAPIDS, Minn. (AP) — There's money in the waste rock piles and tailings basins that litter northern Minnesota's Iron Range.
Magnetation is leading a resurgence in mining on the western end of the Range between Grand Rapids and Hibbing. The company is building its fourth plant, near Grand Rapids. When it opens in January it will tap two nearby tailings basins that United States Steel Corp. left behind in the 1980s and extract the remaining iron from the waste.
Magnetation is part of a growing trend to recover iron and other minerals from mining sites to take advantage of rising metal prices, Minnesota Public Radio reported Monday (https://bit.ly/1hrZroI ).
"Part of it is the prices of many commodities have increased drastically, part is there's a very large expense with developing new mines," said Pat Taylor, professor of chemical metallurgy at the Colorado School of Mines. "So if you can find economic ways to treat material that's already been ground fine and still contains some values, it may have an economic benefit to do so."
Mining companies have clawed iron out of northern Minnesota since the 1880s. First it was high grade ore, then lower grade taconite. After years of tinkering, Magnetation figured out an innovative way to economically process the still-lower grade ore left behind, with a five-story machine that uses permanent magnets to separate out the iron. The concentrate is currently shipped to a steelmaker in Mexico, but soon the ore will go to a plant that Magnetation is building in Indiana with its partner AK Steel.
Lehtinen said Magnetation has an advantage in that the material it's digging up has been mined before.
"We're able to compete against the big boys because we don't have to spend as much money on the drilling and blasting and crushing," he said. "We're mining a material that's already quite fine."
Because the company does not dig up undisturbed areas and its facilities create few discharges it can obtain permits quickly, Lehtinen said.
Next year Magnetation's four plants combined will produce about 4 million tons of iron ore concentrate per year. That's a fraction of the 15 million tons per year produced by Minntac, the Iron Range's largest taconite plant. But the company expects its operations to provide over 400 jobs combined in Minnesota once the new plant fires up.
There's enough waste material and ore left behind in abandoned pits on the Range to supply Magnetation for a century, Lehtinen said.