More than half a century ago, a renowned biologist concluded that wild rice doesn't grow well in lakes that are high in a type of mineral salt that comes pouring off Minnesota's Iron Range.
Now, after three years of lawsuits, legislative wrangling and one of the most comprehensive scientific investigations ever conducted on behalf of a single species, it turns out he was right.
This week, in a decision with far-reaching implications for the state's mining industry and the preservation of its most famous plant, state pollution officials are expected to announce their recommendation for a "sulfate standard" — how much of that salt Minnesota industries can discharge into the clear, calm waters across the state where wild rice likes to grow.
If scientific findings are the guide, which has been the one unifying principal among all the opposing interests, then hundreds of mines, wastewater treatment plants and other facilities may have to come up with new and expensive ways to reduce a pollutant that was long regarded as fairly benign.
"There will be a lot of screaming about this, I'm sure," said Nancy Schuldt, a water quality expert with the Fond du Lac Band of Lake Superior Chippewa, which has pushed the state for years to enforce its long-standing rule to protect wild rice from the mineral salt called sulfate.
Craig Pagel, president of the Iron Mining Association of Minnesota, said the industry cannot estimate the costs of complying, but said: "I'm sure it would be extremely costly. And not just for us."
It's also clear, now, that it's not just wild rice that suffers from too much sulfate. The toxic reaction that occurs in the muck around the plant's roots can affect virtually all types of aquatic flora, or any type of living thing that relies on oxygen, scientists say.
"It's going to affect everything out there," said John Pastor, a biologist at the University of Minnesota Duluth, who ran one of the wild rice studies. "It's going to affect the whole food web."