Air quality agencies carry out enforcement and compliance programs to ensure that sources meet the applicable federal, state and local air pollution control requirements in their jurisdictions. There are several aspects of an agency’s enforcement and compliance program. EPA and state and local air agencies often provide compliance assistance to help the regulated community understand and comply with regulations. In addition, state and local air agencies issue permits that specify applicable regulatory requirements and include the requirements for compliance activities (such as inspections) to ensure permit conditions are being met. When violations are identified, regulators have several options: mandated requirements to install air pollution control devices or process modifications; civil penalties (e.g., fines); supplemental environmental improvement projects; and, in criminal cases, imprisonment. The type of enforcement action can vary considerably from location to location, depending upon many local factors (e.g., air quality, enforcement policies), the type of violation and duration of violation.
EPA oversees state and local enforcement. As noted above, state and local agencies perform a significant percentage of the permitting, compliance monitoring and enforcement under the Clean Air Act. These agencies are required to regularly report to EPA on their enforcement and compliance activities, thus facilitating EPA's oversight. If EPA believes a state or local agency is not appropriately enforcing federal environmental laws, it may take action itself to rectify an alleged violation.
In addition, EPA establishes priority areas every three years to focus civil and criminal enforcement resources and expertise on serious pollution problems affecting communities. These are called National Enforcement Initiatives.