Air Quality Facts
Q: What is ground-level ozone and what causes it?
A: Ground-level ozone is generated when nitrogen oxides (NOx) combine with volatile organic compounds (VOCs) in the presence of sunlight, especially with low humidity and light winds. Coal-burning power plants and motor vehicles are the primary man-made sources in North Carolina. NOx is created when fossil fuels ń like gas or diesel in autos or coal in power plants ń are burned.
Q: We have heard for years that we need ozone to block ultraviolet radiation. Now we hear that high levels of ozone are bad for us. Is ozone good or bad?
A: It is true that we need stratospheric ozone to block ultraviolet radiation. But ground-level ozone causes lung irritation, especially at higher concentrations, so ground-level ozone causes problems.
Q: Rowan County has three ozone monitors, but Cabarrus has none. Is the monitor located on the Rowan/Cabarrus line a good indicator of whatís going on in Cabarrus County?
A: Since ozone tends to be a regional issue, it is a good indicator. Ozone covers a widespread area.
Q: Has air quality improved in North Carolina in the past 20 years?
A: Ozone levels across the state have improved and are expected to continue to improve in spite of our population growth. But parts of the state donít meet the standards set by the Environmental Protection Agency.
Q: What has improved our air quality?
A: A number of programs have had a beneficial effect. The call for NOx State Implementation Plans and CAIR (Clean Air Interstate Rule) are federal programs designed to reduce emissions from coal-burning power plants. The Clean Smokestacks Act is a state program that further reduces coal-burning power plant emissions in North Carolina. The State Attorney Generalís office has filed suit against the Tennessee Valley Authority and other states to reduce their emissions as well.
Q: Has motor vehicle emissionsí testing had a positive effect on our air quality?
A: Yes. The expanded motor vehicle emissionsí testing is having a positive effect on our air quality. North Carolina now has 48 counties that require citizens to get their cars inspected for emissions. That represents 80 percent of the cars in the state. In addition, standards on cars are getting tighter, and fuels got cleaner a few years ago. The sulfur content in gasoline and diesel was lowered significantly. Finally, the motor vehicle fleet gets cleaner every year as old cars die and are replaced by new cars.
Q: What part do motor vehicles play in the ozone pollution in Rowan and Cabarrus counties?
A: Mobile (highway cars and trucks) and non-road sources (such as bulldozers, outboard motors and lawnmowers) produce 59 percent of the nitrogen oxides and 49 percent of the man-made volatile organic compounds in Rowan County. Mobile and non-road sources in Cabarrus produce 82 percent of the NOx and 65 percent of the man-made VOC.
Q: What is the Cash for Clunkers program and how will that help our ozone problem?
A: In July 2009, President Barak Obama signed into law a program that helps you purchase a new, more fuel- efficient vehicle when you trade in a less fuel-efficient vehicle. Some refer to the program as Cash for Clunkers. If old cars are replaced with newer, more fuel-efficient cars, that helps our air quality.
Q: If our air is cleaner, why do we still not meet the Environmental Protection Agencyís air quality standards?
A: The EPA keeps tightening the standards because scientists and medical professionals find that health problems associated with ground-level ozone are not abating sufficiently. Back when the standard was 120 ppb (parts per billion), they determined that it was still affecting peopleís health so it was lowered again. They determined that the public is still getting health problems with the 1997 level of 84 ppb, so the EPA lowered the ozone standard to 75 ppb in 2008.
Q: The Greater Charlotte area (Rowan, Cabarrus, Mecklenburg, Lincoln, Gastonia, Union and part of Iredell) has been designated a moderate non-attainment area. What does that mean?
A: ěNon-attainmentî is a word that the U.S. EPA uses. The Clean Air Act requires the EPA to set national air quality standards for various air pollutants and to re-examine those standards every five years to make sure the standards it sets reflect healthy air quality. If an area does not meet a standard, it is designated ěnon-attainment.î
Q: What are the repercussions of being in non-attainment?
A: Besides the obvious health issues, it would place further restrictions on industry and it could affect whether we receive federal transportation dollars.
Q: What is the chance that the EPA could reclassify our area to ěseriousî non-attainment in the near future?
A: Officials indicate that the Metro-Charlotte region, which includes Rowan and Cabarrus counties, has a 50-50 chance of getting bumped up to a ěseriousî category. If we have another season of high ozone readings this summer, we will not attain the 8-hour ozone standard that the EPA established in 1997. Even if we pass the 1997 standard this summer, we will have to meet a new standard in the next few years. EPA may designate the area ěseriousî for the new standard next March. And if any one of the seven monitors in our area fails, the whole area fails.