## Facts

- The Clean Air Act (CAA) requires EPA to designate areas as attainment or nonattainment for ozone under the National Ambient Air Quality Standards (NAAQS) using multi-year monitoring data.
- EPA had classified the Pittsburgh–Beaver Valley area as a “moderate” ozone nonattainment area based on late-1980s data.
- In November 1993, Pennsylvania requested redesignation of the area from nonattainment to attainment, relying on 1991–1993 monitoring data showing a level consistent with attainment.
- In July 1995, EPA preliminarily determined the area was in attainment.
- During a brief summer 1995 period, monitors recorded a spike in ozone exceedances (including multiple exceedances at certain sites) that, if counted, indicated nonattainment for the relevant period.
- EPA revoked its earlier attainment determination and, by final rule (May 1, 1996), denied Pennsylvania’s redesignation request, concluding the area was not currently attaining the NAAQS and the statutory redesignation criteria were unmet.
- The Southwestern Pennsylvania Growth Alliance petitioned for direct appellate review, arguing EPA (i) unlawfully relied on post-submission exceedances, (ii) should have discounted exceedances attributable to transported ozone and misapplied redesignation criteria, and (iii) inadequately certified under the Regulatory Flexibility Act (RFA).

## Issues

1. Whether EPA acted arbitrarily, capriciously, or contrary to law by relying on 1995 ozone exceedances that occurred after Pennsylvania’s 1993 redesignation submission to deny redesignation.
2. Whether EPA was required to disregard exceedances allegedly caused by transported ozone, or otherwise misapplied CAA redesignation requirements (including “current” attainment and permanent, enforceable emission reductions).
3. Whether EPA’s RFA certification that the denial would not significantly affect a substantial number of small entities was lawful.

## Decision

- The court denied the petition for review and upheld EPA’s final rule denying redesignation.
- EPA permissibly relied on the most recent monitoring data to determine whether the area “has attained” the ozone NAAQS at the time of final agency action; the CAA does not impose the petitioner’s proposed temporal cut-off.
- EPA was not required to excuse exceedances on the theory they were caused by transported ozone, and the agency’s technical judgments about attainment and redesignation criteria were not arbitrary or capricious.
- EPA’s RFA certification was adequate because denial of redesignation did not itself impose new regulatory obligations; any later controls would arise, if at all, in separate actions.

## Legal Principles

- For CAA § 107(d)(3)(E) redesignations, EPA may consider current air-quality data when deciding whether an area “has attained” the NAAQS; the statute does not mandate a fixed deadline after a state submission beyond which data must be ignored.
- EPA’s reasonable interpretation of redesignation requirements, including insistence on current attainment at the time of final action, is entitled to Chevron deference when the statute is ambiguous and the agency’s construction is reasonable.
- Under APA arbitrary-and-capricious review, courts defer to EPA’s technical and scientific determinations regarding monitored exceedances and whether statutory criteria (including permanent and enforceable reductions) are satisfied, absent a clear showing of irrationality or ignored factors.
- The RFA permits certification when the rule at issue does not itself impose significant economic impacts on small entities; speculative effects from potential future controls are evaluated in later rulemakings.

## Conclusion

The Third Circuit sustained EPA’s denial of ozone redesignation for the Pittsburgh–Beaver Valley area, holding that EPA could rely on recent exceedance data to assess current attainment, was not compelled to discount transport-related exceedances, and reasonably certified under the RFA because the denial itself did not create new regulatory burdens.


Sw. Pa. Growth All. v. Browner, 121 F.3d 106 (3d Cir. 1997)