In the fight over proposed mining projects in northern Minnesota, a new player with a surprising amount of clout has emerged -- wild rice. This month, a routine state review of a water quality standard that has lain largely dormant for three decades erupted into an intensely emotional debate about how to protect the state's most iconic plant. On one side are environmentalists and tribal governments who want to keep the rule -- created specifically to protect wild rice from sulfates -- and are insisting that the state enforce its own standard. On the other are mining and business interests who question the science, and who say that industry should not be required to pay millions of dollars in environmental costs that might be pointless. Hanging in the balance are thousands of potential jobs on the Iron Range, the cultural heritage of the Chippewa -- and the graceful sway of wild rice in Minnesota waters. All the players say they want science to prevail in the upcoming two-year review. The decision by the Minnesota Pollution Control Agency (PCA) could ultimately help make or break the proposed Polymet copper-nickel mine near Hoyt Lakes, as well as million-dollar expansions of existing taconite mines. But at this point the science isn't all that clear, and the answers will take awhile. "The whole issue of how sulfate affects wild rice, it's not an easy one," said John Pastor, a professor at the University of Minnesota Duluth who studies wild rice. "And the politicized atmosphere is not helping." Setting a limit Sulfates, mineral salts that occur naturally in the environment, are benign to most living things -- except wild rice. Decades ago John Moyle, a renowned state biologist, studied the relationship between naturally occurring stands of wild rice in northern Minnesota and sulfate concentrations in their waters. He concluded that the rice grew best in mucky water with a sulfate concentration of 10 parts per million or less.

In 1973 the PCA adopted Moyle's standard for waste-water treatment facilities, power plants, mines and other sources. The standard, however, was almost never enforced. Until Polymet. In February the federal Environmental Protection Agency sharply criticized the PCA's environmental review of the $600 million copper-nickel mine -- citing as one reason the state's disregard for its own sulfate standard. Now the state is conducting a second environmental review of the project. This time the EPA insisted that the state clarify how and if the sulfate rule will be applied -- and assess how the project will affect wild rice waters. Officials from Polymet Mining Corp. declined to comment for this story. But Mike Robertson, an environmental consultant with the Minnesota Chamber of Commerce, said the PCA plans to consider the standard in granting industrial permits for any project that will leach sulfate into wild rice waters. "This was news to our folks," he said. But not to the tribes. Since at least 2005, tribal governments have been pressing the state to honor the 1973 sulfate standard in order to protect wild rice, said Nancy Schuldt, water project coordinator for the Fond du Lac Band of Lake Superior Chippewa. "These projects tend to have really high sulfate discharges," she said. Honoring the standard "would require them to install water treatment systems, and they have not been doing that." The issue goes to the heart of what it means to be a Chippewa. Wild rice has historically been a central part of the Indian spiritual culture and diet. Tribes have fiercely held onto the right to gather it through more than 150 years of treaties and years of battle in federal court. But they fear that decades of pollution from mining is hurting the production of rice, Schuldt said. "Where it used to exist, it's gone now, possibly because of changes in water quality from existing mines," she said. 150 buckets

Len Anderson, a biologist and retired school teacher who lives on the Fond du Lac reservation, has been making his own field observations. He said wild rice stands start to wither as mine runoff moves downstream from the Iron Range. There are still a few stands left at the final stopping point, the St. Louis River estuary between Superior, Wis., and Duluth, but they are declining as well, he said. "If we allow Polymet to allow the millions of gallons per day of high sulfate leachate to reach all the way to the estuary, that will jeopardize the remaining wild rice," he said. Perhaps. Robertson, of the Chamber of Commerce, said Moyle's research was based on old data, and says the state needs to consider more recent research. He also says there are waters with higher concentrations of sulfate where wild rice grows just fine. Pastor, the university wild rice researcher, said Moyle's research established the naturally occurring sulfate range for wild rice. "It was not arbitrarily pulled out of the air," he said. But if 10 parts per million is the natural range, the unanswered question, he said, is what's the danger range? He's already pretty sure that the ceiling should be less than 300 parts per million. In tests conducted last year he found that at that concentration, sulfate inhibited root growth, resulting in stunted plants. Now, with a $30,000 grant from the Fond du Lac band and the federal government, Pastor is testing lower concentrations. This past summer Pastor grew wild rice in 150 buckets on a patio outside his lab in Duluth. Over the winter his students will dissect plants, weigh the roots and count seeds in an effort to find that elusive ceiling. "To investigate this takes a couple of years of growing wild rice under different conditions," he said. "But people want it solved all at once. They want the mines to open." Case by case? PCA officials say they, too, want better data and research. In the meantime, the agency has launched a review of the sulfate standard, and last week held public hearings as part of its rule-making process.