Non-attainment area

US-ozone-non-attainment-2007-06

Non-attainment area refers to a geographic region designated by the United States Environmental Protection Agency (EPA) as not meeting the National Ambient Air Quality Standards (NAAQS) for one or more air pollutants. These pollutants may include ozone, particulate matter (PM2.5 and PM10), carbon monoxide, nitrogen dioxide, sulfur dioxide, and lead. The designation of non-attainment areas is a critical component of the Clean Air Act (CAA), a comprehensive federal law that regulates air emissions from stationary and mobile sources.

Designation Process

The process of designating non-attainment areas begins with the EPA setting the NAAQS for the six major air pollutants, which are known as "criteria" pollutants. Once these standards are set, each state must monitor its air quality to determine whether it meets the NAAQS. If a state finds that any part of its territory does not meet the standards for one or more pollutants, it must designate those areas as non-attainment.

Following the state's recommendations, the EPA reviews the air quality data and issues its final designation. States with non-attainment areas are then required to develop and implement a State Implementation Plan (SIP) to improve air quality and achieve attainment of the NAAQS.

Implications of Non-attainment Designation

The designation of an area as non-attainment has significant implications for state and local governments, businesses, and the public. States with non-attainment areas must adopt and enforce regulations to reduce air pollution from various sources, including industrial facilities, motor vehicles, and consumer products. These regulations may include stricter emission controls, vehicle inspection and maintenance programs, and limitations on the operation of certain sources under specific conditions.

For businesses, a non-attainment designation can mean stricter permitting requirements for new or modified sources of air pollution, potentially leading to increased costs for pollution control technologies and operational changes. Additionally, transportation projects within non-attainment areas may be subject to conformity determinations to ensure that they do not worsen air quality.

Achieving Attainment

States are required to develop SIPs that outline how they will achieve, maintain, and enforce the NAAQS. These plans must include control measures, regulations, and other actions that will lead to the reduction of emissions contributing to air quality problems. The EPA must approve these plans, and states are given deadlines by which they must meet the NAAQS.

Once a non-attainment area meets the standards and maintains those standards for a designated period, the EPA may re-designate the area to attainment status. Achieving attainment is a significant milestone that reflects improvements in air quality and public health protection.

Conclusion

Non-attainment areas are a critical focus of the Clean Air Act's efforts to protect public health and the environment from the harmful effects of air pollution. The designation of these areas and the subsequent actions required to achieve attainment of the NAAQS represent a collaborative effort between federal, state, and local governments to improve air quality and ensure a healthier environment for all citizens.

‎