EPA To Enforce New Ozone Standards

The Environmental Protection Agency revised the ozone standard and promulgated a revised particulate matter standard in July 1997. At that time, EPA indicated it would implement the eight-hour ozone National Ambient Air Quality Standards under the less detailed requirements of subpart 1 of part D of title I of the CAA rather than more detailed requirements of subpart 2 requirements.

Various industry groups and states challenged EPA's final rule promulgating the eight-hour ozone NAAQS in the U.S. Court of Appeals for the District of Columbia Circuit. (Litigation on the PM standard paralleled the litigation on the ozone standard and the court issued one opinion addressing both challenges).

In May 1999, the appeals court remanded the ozone standard to EPA on the basis that EPA's interpretation of its authority under the standard-setting provisions of the CAA resulted in an unconstitutional delegation of authority (American Trucking Associations, Inc. v. EPA, 175 F.3d 1027, aff'd, 195 F.3d 4 (D.C. Cir. 1999)). In addition, the court held EPA improperly interpreted the statute to provide for implementation of the eight-hour standard under subpart 1 but also determined EPA could not implement a revised ozone standard under subpart 2.

The EPA sought review of these two issues by the U.S. Supreme Court. In February 2001, the Supreme Court upheld the constitutionality of the air quality standard setting (Whitman v. American Trucking Associations, 121 S.Ct. 903). In addition, the Supreme Court held EPA has authority to implement a revised ozone standard but EPA could not ignore subpart 2 when implementing the eight-hour standard. Specifically, the court noted EPA could not ignore the provisions of subpart 2 that "eliminate[s] regulatory discretion," allowed by subpart 1.

After determining EPA could not ignore the provisions of subpart 2, the court went on to identify several portions of the classification scheme that are "ill-fitted" to the revised standard but left it to EPA to develop a reasonable approach for implementation. Any implementation approach that EPA develops must address the requirements of the CAA, as interpreted by the Supreme Court.

Eight-Hour Ozone Implementation Process

EPA has initiated a process to obtain stakeholder feedback on options the agency is developing for implementation of the eight-hour ozone NAAQS. The EPA plans to issue a final rule on the implementation strategy prior to designating areas for the eight-hour ozone NAAQS.

The implementation rule will provide specific requirements for state and local air pollution control agencies and tribes to prepare implementation plans to attain and maintain the eight-hour NAAQS. States with areas that are not attaining the eight-hour ozone NAAQS will have to develop - as part of its state implementation plan - emission limits and other requirements to attain the NAAQS within the time frames set forth in the CAA. Tribal lands that are not attaining the eight-hour ozone standard may be affected and could voluntarily submit a tribal implementation plan but would not be required to submit a TIP. However, in cases where a TIP is not submitted, EPA would have the responsibility for planning in those areas.

The EPA has placed a variety of materials regarding implementation on the 8-hour Ozone NAAQS Implementation Rule Development Web site.

Updated: April 28, 2003