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What is Non-Attainment?

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The U.S. Environmental Protection Agency (EPA) sets allowable concentration standards for a variety of air pollutants, including ozone. These standards are designed to protect public health and are based on extensive health effects research, including research performed by EPA scientists and by independent researchers. For ozone, this National Ambient Air Quality Standard (NAAQS) is 0.085 parts per million (ppm) averaged over an 8-hour period.

The NC Division of Air Quality is responsible for monitoring pollutant concentrations in North Carolina, and for reporting monitoring results to the EPA. Click here to see locations of ozone monitors in the Triangle area. When monitored pollutant concentrations exceed the standard a certain number of times over a three-year period, even if at only one monitor in an area, that area must be designated a non-attainment area by the EPA.

A non-attainment designation carries certain regulatory consequences. These are the "teeth" in the Clean Air Act. First, a non-attainment area must prove that its long-range transportation plan (road building and widening, transit, etc.) will not result in increased pollution. This is called transportation conformity and is shown through transportation demand modeling, often performed by the Metropolitan Planning Organization (MPO). If an area cannot show transportation conformity, the area becomes ineligible to use or acquire new Federal highway funds.

Secondly, any "point source" industry (an industry that produces air emissions and requires an air quality permit) wishing to expand or locate within the non-attainment area faces strict new source review. New source review means that the industry might have to install the strictest available pollution controls, and purchase pollution offset credits from other industries in the area. In other words, industries will likely look elsewhere before trying to locate within a non-attainment area or before expanding its existing operations. This could negatively impact the region's employment and housing values and could create economic hardships in the area.

Finally, the NC Division of Air Quality must submit a State Implementation Plan (SIP) to the EPA, detailing how the state intends to reduce pollution in order to comply with the standard.