On the grounds of Albemarle High School, a small metal structure sits sniffing the air for pollutants and recording what it finds. Installed in 2008, the Ambient Air Monitoring System has been measuring the amount of ozone and PM2.5, the term for fine solid and liquid particulates 2.5 micrometers and smaller, in Albemarle County.

The levels of the pollutants are then sent to the Virginia Department of Environmental Quality to determine whether or not the air in Albemarle meets the Environmental Protection Agency’s federal standards.

Areas that fail to meet the standards are deemed “nonattainment” by the EPA and are required to then formulate a long-term strategy for reducing the amount of pollutants.

However, according to Carolyn Stevens, a DEQ environmental specialist, man-made and industrial pollutants are only one part of the pollution that contributes to nonattainment.

“People instantly think to curtail industry, and there are things we could do for industry, but there are other sources,” said Stevens, referring to strategies employed in nonattainment areas. “There are also environmental and meteorological issues.”

Ozone is a secondary pollutant, which means that it is created when pollutants such as nitrogen oxides (NOx) or volatile organic compounds (VOCs) are produced and met with direct sunlight and high temperatures.

“[Nonattainment] is dependent on things we have no control over,” said Stephen Williams, director of the Thomas Jefferson Planning District Commission. “The hotter, more humid it is, the more likely you are to have a nonattainment event.”

Ozone levels are measured hourly, and each day the highest eight-hour average is recorded. The past three years’ ozone representations, a selection from the daily data, are averaged together to determine an area’s air quality in terms of ozone. The current maximum ozone level for an area to be considered in attainment by the EPA is a three-year average of 75 parts per billion.

“We’re well under the 75 parts-per-billion mark,” Stevens said, noting that the Albemarle average for 2009-2011 was 67 ppb. “But this summer is proving to be problematic.”

Ozone in Albemarle County is considered a seasonal problem, and the DEQ is only required to monitor the levels in the months of April through October. Because of this, no definitive data is available yet for 2012.

According to Williams, nonattainment for Albemarle County would mean federally mandated pollution austerity measures for citizens and businesses.

“There are control measures that would have to be implemented,” Williams said. “There are several that have already been implemented in other places in Virginia such as the vapor recovery systems on nozzles at gas stations …. There would be an immediate impact on citizens and businesses.”

The control measures could also potentially affect transportation improvements that the county has planned, such as the Western Bypass of U.S. 29, causing VDOT to budget the amount of pollution each project would contribute to the area.

“Transportation improvements [would] have to have no negative net impact on the area,” explained Williams. “If we’re below budget, everything would be fine. If we exceeded the budget, we would have to change our plans.”

Stevens was asked if the proximity of the air monitoring system to the proposed Western Bypass route, which passes directly behind AHS, Jack Jouett Middle School and Greer Elementary School, would have an effect on the ozone levels taken there.

Stevens expects the new road to have little impact on the data.

“It will conceivably get people moving and alleviate congestion,” said Stevens, referring to drivers in the area. “Cars sitting at traffic lights create more NOx and VOCs [than moving vehicles], which contribute to the ozone levels.”

Moreover, says Stevens, the location of the bypass could mean that potential pollutants would be detected somewhere other than Albemarle.

“Where we place a monitor has a lot to do with the pollutant we want to measure,” said Stevens in a follow-up email. “Ozone concentrations tend to be highest about 10 – 15 miles downwind of the urban areas.”