Editor’s note: This is the first article in a continuing series that looks at air quality in Tooele County.
From 2007 to 2012, Tooele County made substantial strides toward improving its air. And then 2013 happened.
When the Utah Division of Air Quality began monitoring air quality in earnest in 2007, its sensors counted almost 90 days of moderately polluted and unhealthy air during the last six months of the year. By 2012, Tooele had dropped to just 70 days with pollution advisories.
That trend continued in 2013, with just 59 days of noticeably polluted air. But of those days, 12 were considered unhealthy for sensitive populations — the highest number of unhealthy days on record for Tooele County.
Though air pollution represents a substantially larger problem for other parts of the state — for comparison, Salt Lake and Utah counties saw 30 and 36 days, respectively, of unhealthy air in 2013 — Tooele County’s own setback over the last year served as a reminder to local experts and residents alike of the environmental challenges Great Basin communities continue to face.
Tooele County, like most of northern Utah, saw its worst air quality in years last winter, when a series of weather events proved the perfect storm for unhealthy air. Extended periods of single-digit temperatures, with little air circulation into or out of Utah’s mountain valleys, resulted in a stubborn temperature inversion.
While the inversion remained in place, pollution continued to build above Utah’s cities, including Tooele. The resulting concentration of pollutants surpassed concurrent pollution levels in all major U.S. cities and urban areas, an event that garnered national headlines and a lengthy article in the New York Times.
“The fact that we had plans in place [to address inversion-related pollution], and that meteorological conditions overcame our plans, is something we need to address,” said Bryce Bird, director of the Utah Division of Air Quality.
However, 2013 was far from the first time Utah’s inversion has created serious air quality problems for the state.
“Our air quality has been improving, but is always variable with the weather,” said Bird.
The infamous inversions of 2013 contrasted a period of unusually clean air, which made the problem all the more apparent, he noted. Tooele itself exceeded federal standards for small particulate pollutants at least three times in 2013, after the area had gone three years without a single violation. But Bird quickly added that 2007, 2004, and countless other years saw inversions not unlike recent phenomena.
The state began monitoring Tooele’s air quality in earnest in July 2007, not long after the Environmental Protection Agency included parts of the county with the Salt Lake City nonattainment area for PM 2.5 — a kind of catch-all category for tiny particles of varying composition. These particles, which are roughly 1/40th the diameter of a human hair, are considered hazardous to human health regardless of composition.
Because they are so small, PM 2.5 particles can work their way down into the lowest chambers in the lungs, where gasses are exchanged. In high concentrations, PM 2.5 causes irritation and inflammation in the lungs. It is a known trigger for asthma and other chronic respiratory illnesses, and may be linked to a wide variety of diseases in healthy individuals, including heart and lung disease, according to the EPA’s AIRNow informational website.
According to Bird, this kind of particulate pollution is a common problem in urban areas, particularly during the winter, because car emissions are the top source of PM 2.5. But they also come from a wide variety of sources common to modern-day urban life — hairspray, cleaning supplies and other consumer products all make the list.
“Everything we do has an emissions outcome,” he said.
PM 2.5 is one of several pollutants the EPA regularly monitors and regulates under the Clean Air Act, a major congressional act signed into law by President Lyndon Johnson in 1963. Once every five years, EPA officials consider current rules for each of these major pollutants to determine whether new scientific knowledge of that pollutant warrants different regulations.
That was the case in 2006, when the EPA implemented a new rule limiting the acceptable level of exposure to PM 2.5 to 35 micrograms per day. Because PM 2.5 levels throughout the Wasatch Front regularly exceed this standard, Bird said, the EPA portioned populous communities throughout the corridor into three “nonattainment areas.”
The EPA included portions of Tooele County — mostly populous portions of Tooele Valley — in a nonattainment area that primarily comprised Salt Lake County, but also portions of Box Elder and Weber counties. Bird said the federal agency primarily decided to include Tooele on account of the large number of commuters who travel from Tooele Valley to work in Salt Lake County on a daily basis, therefore contributing to Salt Lake’s ongoing pollution woes.
As a direct result of the decision, Tooele is subject to many of the same regulations intended to curb emissions in Salt Lake, even though Tooele does not, in general, see the levels of pollution common to Salt Lake County.
Since the decision, officials with the Utah Division of Air Quality have drafted and begun to implement a State Implementation Plan that is designed to bring PM 2.5 pollution within federally-mandated levels by the year 2019. Early rules included in the state’s plan brought air quality monitoring, reporting and forecasting to Tooele County for the first time in 2007.
More recent regulations have implemented a mandatory no-burn period for the county — a rule that bars Tooele residents from burning solid fuels such as wood and coal on days of poor air quality during winter months — and restrictions on small businesses that employ coatings, solvents or other sprays that include volatile organic compounds.
The State Implementation Plan remains a work in progress, said Mark Berger, who helps oversee the rulemaking process at the Utah Division of Air Quality. The division just recently found out that, as per a court ruling, the state will have to resubmit its entire plan according to the requirements of a different section of the Clean Air Act — a development that has delayed the state’s continued progress toward the 2019 goal.
In the meantime, with the EPA set to review PM 2.5 regulations in 2016, the state is working toward a moving target, Berger said.