The state of Minnesota has abruptly pulled out of a four-year, $1 million research project to identify the sources of mercury pollution in the St. Louis River on the Iron Range, a decision that stunned the Fond du Lac Band of Chippewa and dismayed federal regulators.

The mercury contamination, which makes much of the river's game fish inedible for children and young women, is particularly worrisome because 1 in 10 infants on the North Shore of Lake Superior have been found to have unsafe levels of mercury in their blood. About 1 in 100 have levels high enough to harm neurological function, according to state health officials. The river's estuary is also a critical breeding ground for fish in western Lake Superior.

Officials from the Minnesota Pollution Control Agency (PCA) said they are committed to reducing mercury pollution in the river and in the 10 percent of the state's waters that have unusually high levels. But, they said, the agency's lead scientists believe the state first needs more research on how mercury behaves in nature and why mercury levels in fish from the St. Louis River are significantly higher in than those elsewhere.

Others with a stake in cleaning up the river say that sources of mercury are well-known: a combination of air emissions from power and taconite plants, and sulfate pollution. They say the federally funded research project would have provided some badly needed answers.

"The St. Louis River is [our] single most important fishing source," said Nancy Schuldt, water project coordinator for the Fond du Lac Band of Lake Superior Chippewa, whose members rely on the river as a source of food. "We simply can't walk away from this."

This week Water Legacy, an environmental advocacy group, asked the U.S. Environmental Protection Agency (EPA) to hold a public meeting to discuss the project and the state's actions. The public and other interested groups deserve a chance to weigh in on the decision, said Paula Maccabee, Water Legacy's attorney.

"Stepping away is irresponsible," she said.

Largest estuary

The St. Louis River drains Minnesota's Iron Range before spreading out into the nation's largest freshwater estuary between Duluth and Superior, Wis. — the primary incubator for aquatic life in western Lake Superior. The estuary, contaminated by a century of industrial activity, is a primary focus of the EPA and has received millions of dollars for remediation through the federally funded Great Lakes Initiative.

The state first tackled the river's mercury problem more than 10 years ago, when it launched an effort under the federal Clean Water Act to identify the sources of pollution and to develop a plan to fix it. But that was halted when the PCA opted to first develop a statewide plan to reduce mercury emissions, making Minnesota one of the first states to do so. Under that plan, which calls for gradually reducing Minnesota's mercury air emissions by two-thirds, 90 percent of the state's lakes and rivers would eventually see fish contamination levels fall to safe levels.

But that's not true for about 10 percent of the state's lakes and rivers. For reasons that are not well understood, they are mercury "hot spots" where levels are significantly higher, and in the St. Louis River and the estuary they are among the highest of all.

Four years ago the EPA offered money from Great Lakes Initiative to address problems in the St. Louis River, creating a partnership between the federal government, Minnesota, Wisconsin and the Fond du Lac band to manage it. The project, which has cost just under $1 million to date, would have compiled reams of environmental data held by the state and industry, plus new data collected from the river and its tributaries.

It also would have included new research on how mercury behaves in the environment from a major effort partially funded by the taconite industry that is now underway at the Minnesota Department of Natural Resources. The industry has a keen interest because the research is designed to address whether sulfate, a dissolved mineral that flows from water treatment plants and iron ore pits, plays a role in transforming mercury into a form that gets into the food chain and eventually accumulates in predator fish like northerns and walleye.

'Stunned'

The problem, according to state documents and e-mails, was the computer modeling program that the St. Louis River project would used to crunch data and identify the sources of mercury. A year ago, state scientists raised questions internally about using the computer model for the mercury project, called a TMDL.

Then in February, when it came time for all the partners to sign off on the mercury research plan, Minnesota officials suddenly informed the EPA and others that the state would no longer participate because they feared that the study would produce unreliable results.

"There is something different about these waters," Shannon Lotthammer, director of PCA's environmental analysis division, said in an interview this week. She said the agency's top scientists believe the computer analysis uses assumptions that might be inaccurate, and that could lead to decisions "that won't solve the problem." Lotthammer added, however, that the state is willing to work with the EPA and the other partners in addressing other pollutants in the St. Louis River.

But Alie Muneer, the Chicago EPA official leading the project, said Minnesota officials had never before expressed its concerns and that she was surprised and puzzled by the suddenness and "the magnitude" of the decision.

"With any TMDL there is always a level of uncertainty involved," Muneer said.

She also pointed out that mercury assessments have been successfully completed on rivers in other states — some with less information than would be used in the St. Louis River assessment.

As designed, it "would have produced a scientifically defensible TMDL," she said.

Schuldt said she knew PCA scientists had concerns about the computer model, one of several that would have been used. But she did not know that "it was a deal breaker," and state officials never suggested an alternative, she said. "We all felt a little stunned."

In a March letter to the EPA, Commissioner John Linc Stine of the PCA said that Minnesota is committed to resolving the mercury problem, that it is putting together a research proposal that will build on the sulfate research the DNR is conducting to better understand the chemistry and that it will seek funding for it as it goes along.

Muneer said she hopes differences can still be resolved at a May meeting about the project and the computer model.

But Schuldt said that if the project stalls, the EPA is not likely to devote more resources to finding ways to reduce mercury in the river and that she finds the prospect disheartening.

"If you walk away from this now, we are sunk," she said.

Josephine Marcotty • 612-673-7394