The Citizens Board of the Minnesota Pollution Control Agency will get an update Tuesday on research under way to determine if the state should change its standard for sulfate in wild rice waters.
Sulfate comes from wastewater treatment plants and mining operations. Several taconite mines exceed the standard of 10 parts per million in wild rice waters.
Native Americans and other groups have long said that high levels of sulfates can kill the state's natural wild rice beds.
The state recently began trying to enforce the 10 ppm standard in lakes and rivers, but the Minnesota Chamber of Commerce sued, saying the standard is vague and arbitrarily applied.
One question researchers are trying to answer: Which lakes and rivers should be classified as waters that produce wild rice?
Shannon Lotthammer, director of the Environmental Analysis & Outcomes Division of the MPCA, said the standard was set back in 1973 and mentioned both cultivated paddy rice and natural wild rice.
"It was clear that it was natural stands -- it was used by humans and also used by wildlife," Lotthammer said, "but as far as what specific waters are waters used for production, there's not inventory that lists all those waters. So right now it's a case-by-case determination. We'd like to add more clarity to that if we can."
The MPCA is supervising ground-breaking research about exactly how sulfate acts in wild rice beds. Lotthammer said one contractor is designing a new experimental method to get the answers researchers need.
"It takes time to develop that method, particularly since there isn't a national protocol for doing this kind of plant testing that we're doing," Lotthammer said.
Lotthammer expects results from the research in about two years.
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