Judge rejects PCA’s proposed sulfate limit for wild rice waters

A state administrative law judge has flatly rejected a plan by the Minnesota Pollution Control Agency to abandon the statewide 10 parts-per-million limit for sulfate pollution in wild rice waters in exchange for a lake-by-lake system with varying...

Wild rice harvested on Perch Lake on the Fond du Lac Reservation gleams in the sunlight. (file photo / News Tribune)
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A state administrative law judge has flatly rejected a plan by the Minnesota Pollution Control Agency to abandon the statewide 10 parts-per-million limit for sulfate pollution in wild rice waters in exchange for a lake-by-lake system with varying limits.

Administrative Law Judge LauraSue Schlatter, in an 82-page opinion approved by the state’s chief administrative law judge and released Thursday, considered 1,500 written comments on the proposed changes in state law and held five public hearings that drew a combined 300 people.

Schlatter ruled against repealing the existing, statewide 10 ppm limit due to the PCA’s “failure to establish the reasonableness of the repeal, and because the repeal conflicts” with the federal Clean Water Act.

The judge also ruled against the PCA plan to develop “equation-based” limits for specific lakes and rivers that hold wild rice because it wasn't firm enough, it “fails to meet the definition of a rule” under state law “and is unconstitutionally void for vagueness.”

Schalter even rejected the state’s preliminary list of 1,300 lakes and rivers where the agency believes viable wild rice stands exist, places where the new rules would have applied, because the list itself violated federal law.


“The MPCA has not presented facts adequate to support the reasonableness of the proposed repeal of the 10 (ppm) sulfate standard without a replacement standard that is equally or more protective of wild rice waters,” the judge concluded before warning the PCA against re-submitting a similar plan. “Because some of the defects in the rule are defects in foundational portions of the proposed rules, the Administrative Law Judge advises the Agency against re-submitting the rule for approval ... unless it addresses the defects in the wild rice water sulfate standard and the list of wild rice waters.”

The judge’s ruling appears to leave the statewide 10 ppm limit for sulfate pollution in effect, but it remains unclear if or when that rule will ever be enforced. A current state law prevents the PCA from enforcing the limit in any pollution discharge permit. While the old sulfate law has been on the books since 1973, it has not been widely enforced, and several taconite iron ore operations and some municipal wastewater treatment plants upstream of wild rice stands are believed to be in violation.

PCA officials said they were still reading the decision Thursday and weren't ready to interpret the impact.

“We just received the ALJ report. We will need to read and evaluate what the ruling says before offering any public comment,” said Dave Verhasselt, the agency’s director of communications.

Kelsey Johnson, president of the Iron Mining Association of Minnesota, which opposed the PCA’s plan, said the PCA’s “first brush” at changing the sulfate rule “clearly wasn't adequate.”

“I think the formula really had a lot of flaws and errors in the way they (PCA) approached it. They didn’t look at all the factors that impact wild rice other than sulfate - things like water depth,” Johnson said, adding that she believes the judge’s ruling now puts the issue back in the hands of the Legislature to decide how to regulate sulfate.

But environmental groups also were claiming victory, saying the judge rejected the rule because it abdicated the state’s responsibility to protect wild rice and human health from the impacts of sulfate pollution under the federal Clean Water Act.

“We’ve been moving ahead since 2011 under a threat that there would be a change in the state law that would remove the need for the mining industry to meet any sulfate standard. But the judge has clearly rejected that on its face. … She said a rule is needed to protect wild rice and protect water quality,” said Paula Maccabee, attorney for the group Water Legacy, which has pushed to retain the statewide sulfate limit. “We now have a neutral third party who said that (the PCA's proposal) doesn’t meet state rules and doesn't meet the Clean Water Act. The good news is that the rule of law still matters.”


Scientists have found that sulfate - which can come from sewage effluent, mine discharges and other industrial processes - is converted to sulfides in the sediment of many wild rice lakes and rivers. The rate of that conversion changes depending on the amount of carbon and iron in the water (generally, more sulfides with high carbon, fewer sulfides with high iron). It's those sulfides that prevent wild rice from thriving in some areas; the proposed new rule would have studied the water chemistry of each wild rice lake and river to determine what sulfate level they could handle and still grow wild rice.

Research also appears to show that higher sulfate and sulfide levels increase toxic methyl mercury, a pollutant already targeted because of its potential impact on human health.

Mining supporters have both worked to repeal the old limit and stop the PCA’s proposed changes, saying no limit is needed - that there is no major crisis with wild rice downstream of where mines operate. Business and government groups say the rule would be too costly to meet.

Iron Range leaders warned during comments on the rule change that enforcing sulfate limits could end mining as we know it, closing taconite plants and putting thousands of people out of work. Larry Sutherland, head of U.S. Steel's Minnesota mining operations in Keewatin and Mountain Iron, which employ some 1,700 miners, testified in October that adding reverse osmosis treatment to remove sulfate at Keetac's wastewater system could cost $200 million, a price tag that would be prohibitive for the plant to remain competitive in the global iron ore market. The implication is that the plant would close if sulfate limits are enforced.

The PCA said about 135 facilities are within 25 miles upstream of wild rice waters and would be the most likely ones affected by any sulfate rule enforcement.

Environmental groups and tribal resource officials want to stick with the current, statewide sulfate standard of 10 parts per million, saying it's simple and potentially effective at protecting wild rice if it's enforced.


John Myers reports on the outdoors, natural resources and the environment for the Duluth News Tribune. You can reach him at
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