MISSOULA - Air quality in the Missoula Valley has improved since the 1990s when wood stoves still heated homes and cars idled at Malfunction Junction for several turns of the light.
But as the city’s population continues to grow, air quality experts said it’s getting hard to maintain federal air-quality standards and, because of it, a number of changes are being considered to keep the city’s air within regulation.
That includes phasing out wood-burning stoves, doing away with oxygenated fuels, dust abatement and outdoor burning.
“With our growing population, it’s getting harder and harder to meet our national ambient air-quality standards, especially with fine particulate,” said Ben Schmidt. “We have to continue looking at ways to improve the air quality on a per-person basis as the population grows.”
Schmidt said the City-County Air Pollution Control Board currently follows a set of rules that don’t gel with state requirements adopted by the 2019 Legislature. Some of the changes are minor and are intended to bring the rules into compliance.
But others are more impactful, including a proposed ban on recreational fires during periods of an air alert or warning.
“Right now, you can technically go out and have a recreational fire outside the city limits during an air alert, but people can’t heat their home with a wood stove. That doesn’t seem to make sense,” said Schmidt. “With the rise of recreational fires increasing – it’s becoming more and more popular – it needs to be addressed in the wintertime when we have these air alerts.”
The proposed changes would also address industry by allowing a two-year extension to an air-quality permit when construction isn’t completed within the first 36 months of the initial permit.
Schmidt said he doesn’t see that change being used very often, though he believes the option is necessary given today’s challenges around supplies and potential zoning delays.
The changes would also phase out oxygenated fuels. Currently, gas stations are required to have 10% ethanol in their gasoline from November through February. In the 1990s, Schmidt said, the oxygenated fuels program helped improve air quality, but those benefits have since diminished.
“What we’re proposing, when we receive authorization from state and federal government, that we would cease the oxygenated fuels program,” Schmidt said. “From an air-quality point of view, it really has no benefit anymore, so it really doesn’t belong here.”
The changes would also impact outdoor burning and make it possible for major burners, like the U.S. Forest Service or large landholders, to move vegetation off-site to a curtain burner for a cleaner burning process.
The changes would also phase out wood-burning stoves once and for all, Schmidt said.
“Since 1994, we have been requiring that all non-EPA certified stoves be removed, and no wood stoves have been installed legally inside the air stagnation zone,” Schmidt said. “What we’re proposing is that even these Class 1 stoves now be removed. It’s been well over 20 years.”
To achieve that, the changes would require that a wood stove be removed when a property changes ownership within the regulated area, which includes the city and surrounding areas.
Schmidt said wood stoves would still be permitted in Seeley Lake, though newly installed burning devices must comply with federal 2020 emission standards.
“There was a new standard passed by the EPA that all new manufactured stoves installed had to meet emissions standards,” Schmidt said. “In this fragile area, this air shed where we have a hard time meeting standards, they can only put in the best devices.”
Schmidt said Missoula’s air-control program can only regulate certain pollutants, like dust and other particulates related to smoke. Those rules don’t currently extend to greenhouse gasses and carbon dioxide.
“Greenhouse gas pollutants haven’t been classified into that category yet,” he said. “Unless that changes at the federal level, especially for industrial sources, we’re not the right venue to take that on.”