The mercury problem

As we report this week (see page 4B), the Minnesota Department of Health, or MDH, has issued new fish consumption guidelines, with stricter recommendations for lakes in northeastern Minnesota, including St. Louis, Lake, and Cook counties.
The stricter recommendations reflect MDH’s better understanding of the effects of mercury, particularly on fetuses and young children, rather than an increase in mercury levels in the region’s fish populations. But that’s slim comfort for those of us who consume fish from lakes in the Arrowhead.
The situation could be worse. Over the past two decades, a sustained effort by the Minnesota Pollution Control Agency to reduce the amount of mercury entering the state’s environment has been largely successful. Back in 2005, the state’s industries discharged or emitted about 3,300 pounds of mercury into the environment every year. That may not sound like much, but even barely detectable levels of mercury in our lakes readily “bioaccumulates” in fish tissue to levels that can be harmful to humans.
But one politically powerful industry has bucked the best efforts of the MPCA to reduce its mercury emissions. Over the past 20 years, as most other industries slashed their mercury output, in some cases dramatically, northeastern Minnesota’s taconite plants have made little progress and now account for more than 50 percent of the mercury emissions in the state according to MPCA data.
Both U.S. Steel and Cleveland-Cliffs maintain that the available technologies can’t be relied upon to consistently meet the 72 percent reduction required under the state rule enacted decades ago.
A top MPCA engineer disagrees with this assessment, suggesting that there is relatively new technology that could well meet the standard. At a minimum, it would allow for a significant improvement over the current level of emissions, even if it couldn’t consistently reduce emissions by 72 percent.
Instead, the industry has resorted to the same tactics it has successfully employed for decades — denial followed by delay.
As other industries took serious steps to clean up their act, the state’s mining industry issued technical reports claiming there was no feasible means of doing so in their case. That’s always the industry’s claim.
In an effort to encourage companies like U.S. Steel and Cleveland-Cliffs to invest in exploring treatment options, the state Legislature approved over $16 million in grant funding for the industry back in 2023. To date, the companies have shown little interest in tapping the funds to work toward a solution. Northeastern Minnesota is just supposed to live with the consequences of their pollution.
The situation puts the lie to a common refrain heard here in Minnesota, especially from supporters of new copper-nickel mining proposals — that we need to mine here in Minnesota because we have strong laws that protect the environment.
In truth, Minnesota does have strong environmental laws, but that’s only half of the battle when it comes to protecting the environment. Where Minnesota has fallen woefully short time and again has been when those tough laws meet the political clout of an industry that doesn’t share the desire of Minnesotans for a clean environment, at least not when it impacts their bottom line.
The state has proven ineffective at curbing the environmental harms of the taconite industry, and that track record should alarm every Minnesotan as proposals for far more dangerous forms of mining, involving sulfide-based ores, are advancing.
While the federal EPA has, at times, provided a bit of backbone to state regulators, by pushing them to start enforcing pollution standards on the mining sector, that support has now vanished entirely under the current administration, as President Trump recently suspended enforcement of federal mercury regulations for at least two years.
In other words, there is little reason to think that our current political leadership can be counted on to address concerns like mercury, even as scientific studies have shown that northeastern Minnesotans have legitimate reason for concern.
A 2011 study of mercury levels in the blood of infants within the Lake Superior basin found that mercury levels were consistently higher in infants from northeastern Minnesota than adjacent parts of northern Wisconsin or the Upper Peninsula of Michigan. If the problem with mercury deposition was predominantly from global or national sources, you would expect to see similar levels of the toxin in infants across the three states. Instead, northeastern Minnesota stands out.
It’s only natural to ask why that is. Unfortunately, the question invariably makes state regulators nervous. It’s time for honest answers.