Minnesota's air quality currently meets national standards, but other significant pollution problems face the state.
Nearly 1,300 factories, power plants, and even hospitals in Minnesota are permitted to send specific pollutants into the air. The state and federal governments coordinate to monitor and control the pollution.
However, another source of pollution goes unregulated and is a big part of the toxic pollution problem: our automobiles, boats and ATVs.
FEW COMPLAINTS FROM THE EPA
Minnesota annually puts more than 72,000 tons of toxic pollutants into the air. That amounts to nearly 29 pounds for every person in the state.
Those pollutants include mercury, which can damage the human nervous system; formaldehyde, which causes cancer; dioxin, which can cause reproductive, hormonal, and developmental problems; as well as hundreds of other substances that we don't know much about.
Apart from these toxins are "criteria pollutants," which are carbon monoxide, lead, nitrogen dioxide, particulate matter, ozone, and sulfur dioxide.
Minnesota has comparatively clean air, thanks in part to steady winds. For some pollutants, the state imposes more strict emission standards than the federal government. Minnesota is also a national leader in reducing mercury pollution.
Minnesota writes its own rules for meeting standards set by the federal Environmental Protection Agency, and the state does most of the rule enforcement. (Read MPCA's annual pollution report to the legislature.)
Some states, notably Texas, oppose the federal government over many environmental issues. But Minnesota does a good job of enforcing pollution laws, said Jeff Connell of the state Pollution Control Agency.
"We don't have EPA coming in and checking over what we do," Connell said. "We feed them information about our compliance and enforcement efforts; they nitpick a little bit but overall recognize that we have a good well-rounded program."
The MPCA issues about 150 enforcement actions each year. They can be a simple notice that a violation has occurred, or a legal requirement to take certain steps to correct the violation. Fines depend on the damage to the environment and the history of the company, but the average fine is $4,000.
Enforcement actions are rare, Connell said. Mostly the agency works with industry to keep emissions below permitted levels.
"We catch non-compliance early on," he said. "We help companies figure out what they did wrong, get back into compliance before it becomes a big deal."
The limits in the permits are mostly based on health benchmarks. In theory, permitted pollution is kept below a level that threatens human health.
"THE ENEMY ... IS US"
Surprisingly, point sources such as power plants and factories contribute 14 percent of the state's toxic air pollution. Two-thirds of the toxic chemicals come from the tailpipes of automobiles, ATVs and boats.
"As Pogo said, I've seen the enemy and he is us," said Bob Moffitt, spokesman for the American Lung Association in Minnesota.
"Our tailpipes produce the single largest chunk of air pollution that the state sees, both in particulate pollution — a lot of that comes from diesel — and also ozone, which is a big emission from gasoline-powered vehicles."
The Twin Cities metro area has so much fine particulate pollution that it could fail to meet the new standards expected from the federal government next year. And in 2014, a more strict standard for ozone could be issued.
Because cars and trucks are a large contributor of both fine particulates and ozone pollution, metro area residents could be asked to change their habits, said Catherine Neuschler of the MPCA.
"Not just telling people to stay inside, but don't mow your lawn. Don't fuel your cars until after sunset, because of the sunlight contribution to ozone," Neuschler said. "That certainly is a fairly common strategy, and I'm sure one we would be thinking about."
If the Twin Cities area fails to meet federal standards, tighter limits on certain industries would automatically kick in, Neuschler said. That could mean new hurdles for businesses that want to expand or build here.