936 F.3d 597
D.C. Cir.2019Background
- This appeal challenges EPA’s 2015 revisions to the primary and secondary national ambient air quality standards (NAAQS) for ozone, lowering both standards from 0.075 ppm to 0.07 ppm while retaining the 8-hour averaging time and the three-year average/4th-highest form.
- EPA relied on clinical studies, epidemiologic evidence, CASAC recommendations (which suggested a range of 0.06–0.07 for the primary standard), exposure and risk assessments, and public comments in promulgating the rule.
- For the secondary (welfare) standard, EPA analyzed tree growth loss, crop yield loss, and visible foliar (leaf) injury using the W126 cumulative seasonal exposure index but kept the existing 8-hour form and three-year averaging method instead of adopting a single-year W126 form.
- EPA included a grandfathering provision allowing certain pending PSD (preconstruction) permit applications completed or publicly noticed before the new NAAQS effective date to rely on the prior (2008) standard for demonstration of compliance.
- Petitioners: industry and several states argued the standards were overly stringent or that EPA failed to consider attainability/background ozone and socioeconomic impacts; environmental/public-health groups argued standards were too weak and challenged the grandfathering.
- The D.C. Circuit upheld most challenges but: remanded the secondary standard for reconsideration on two specific points (three-year W126 benchmark and failure to set a level for visible leaf injury) and vacated the grandfathering provision as inconsistent with the Clean Air Act.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Primary standard level and form (0.07 ppm; three-year/4th-highest form) | Environmental petitioners: 0.07 ppm and the retained form are insufficiently protective; will allow harmful exposures. Industry/states: EPA failed to justify departing from 2008 standard. | EPA: decision based on weight of clinical studies, epidemiology, CASAC advice (policy weighed by EPA), exposure assessments; retained form supported by exposure analysis. | Upheld: EPA provided a rational explanation; primary standard and form upheld. |
| CASAC departure and adversity determinations (primary) | Envtl: EPA failed to explain departing from CASAC on adversity (e.g., lung function decrements at ~0.06 ppm). | EPA: CASAC’s recommended range was scientific; choice within range is a policy judgment; EPA reasonably adopted ATS guidance and interpreted evidence. | Upheld: EPA adequately considered CASAC and reasonably exercised policy judgment. |
| Secondary standard benchmark and form (use of three-year average vs single-year W126) | Environmental petitioners: EPA improperly used a three-year-average W126 benchmark and did not lower the level to protect against single-year damaging exposures; also should adopt single-year W126 as form. | EPA: used three-year benchmark and retained 8-hour form because metrics are correlated and agency focused on multi-year welfare effects. | Remanded: EPA failed to show that its three-year-average benchmark protects against unusually damaging single-year exposures; remand to lower or justify benchmark or adopt single-year W126. |
| Visible leaf injury (secondary) | Envtl: CASAC recommended ~10 ppm-hrs to reduce foliar injury; EPA failed to set any level despite CASAC’s view that foliar injury is an adverse welfare effect. | EPA: uncertainties and complexities precluded setting a quantified level; believed tree-growth protection afforded some incidental protection. | Remanded: EPA’s refusal to identify any protective level was arbitrary; must reconsider. |
| Consideration of costs/background ozone/other cross-cutting claims | Industry/states: EPA must consider socioeconomic/energy impacts and background ozone when setting NAAQS; otherwise nondelegation concerns. | EPA: statute forbids cost consideration in setting NAAQS; background ozone addressed during implementation/enforcement (exceptional events, transport provisions), not in NAAQS-setting. | Rejected: Court held Whitman controls—costs/impacts are not factors in setting NAAQS; EPA need not account for background ozone when setting standards; no nondelegation problem. |
| Grandfathering of pending PSD permits | Envtl: Grandfathering violates plain text of §165(a) requiring demonstration against "any" NAAQS; applicants must meet the standard effective at permit decision. | EPA: ambiguous conflict between §165(a) and §165(c) (one-year requirement to grant/deny) justified grandfathering; reasonable Chevron interpretation. | Vacated: Chevron step one—Act unambiguously requires compliance with any effective NAAQS; EPA exceeded statutory authority by grandfathering. |
Key Cases Cited
- Whitman v. Am. Trucking Ass'ns, 531 U.S. 457 (2001) (Congress barred cost consideration in setting NAAQS)
- Chevron U.S.A., Inc. v. Natural Resources Def. Council, 467 U.S. 837 (1984) (agency deference framework)
- Mississippi v. EPA, 744 F.3d 1334 (D.C. Cir. 2014) (prior NAAQS do not bind EPA; standard must be "requisite")
- Motor Vehicle Mfrs. Ass'n v. State Farm, 463 U.S. 29 (1983) (arbitrary-and-capricious review requires reasoned explanation)
- Sierra Club v. EPA, 762 F.3d 971 (9th Cir. 2014) (permitting decision must apply standards in effect at permitting decision; related permitting precedent)
- American Farm Bureau Fed'n v. EPA, 559 F.3d 512 (D.C. Cir. 2009) (agency must explain rejecting CASAC’s scientific conclusions)
- New York v. EPA, 443 F.3d 880 (D.C. Cir. 2006) (statutory interpretation and limits on expansive readings of words like "any")
- Andrus v. Glover Constr. Co., 446 U.S. 608 (1980) (express statutory exceptions preclude inferring additional exceptions)