Mississippi v. Environmental Protection Agency
744 F.3d 1334
D.C. Cir.2013Background
- This case consolidates challenges to EPA's 2008 revisions of the ozone NAAQS (primary and secondary).
- The 1997 ozone NAAQS was 0.08 ppm (8-hour); the 2008 rule lowered the primary to 0.075 ppm and made the secondary identical to the revised primary.
- CASAC recommended a lower level (0.060–0.070 ppm) and a cumulative seasonal secondary standard, which EPA largely did not adopt.
- The court reviews EPA's NAAQS decisions under a highly deferential APA standard, focusing on rationality and substantial evidence.
- Mississippi and industry petitioners challenge the primary standard; public health and environmental petitioners challenge the adequacy of the secondary standard.
- The court ultimately remands the secondary standard for reconsideration, denies challenges to the primary standard, and preserves the standard in place pending remand.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Was EPA's choice of 0.075 ppm for the primary NAAQS arbitrary? | Mississippi argues the level is not supported by evidence and fails to compare 2008 to 1997 risk data. | EPA reasonably weighed evidence, uncertainties, and CASAC input to set a protective, yet not excessive, level. | Not arbitrary; standard rationally supported. |
| Did EPA adequately consider margin of safety in setting the primary NAAQS? | Petitioners contend EPA did not sufficiently account for vulnerable populations and margin of safety. | EPA consistently considered sensitive subpopulations and set a standard appreciably below 0.080 ppm. | Margin of safety adequately considered; not arbitrary. |
| Did EPA properly justify departing from CASAC recommendations on the primary level? | CASAC recommended lower levels; EPA allegedly failed to provide sufficient rationale for departure. | EPA explained policy considerations and uncertainties, and CASAC did not provide a precise scientific basis for 0.070 ppm. | EPA's explanation satisfactory under statute; departure justified. |
| Is the secondary NAAQS identical to the revised primary permissible without additional explanation? | Rule requires a separate substantial justification for the secondary level, not just mirroring the primary. | EPA relied on new vegetation evidence and found primary protection largely overlapped with secondary. | Remanded for further explanation or reconsideration; identical standard not sustained. |
| Did EPA's handling of IQA/Info Quality Act and CASAC involvement render the rule unlawful? | EPA violated IQA and failed to peer-review reanalysis as claimed. | IQA guidelines are nonbinding; CASAC involvement and explanations were adequate. | IQA concerns not demonstrated to render the rule unlawful; remand on secondary remains independent. |
Key Cases Cited
- American Trucking Ass’ns v. EPA, 283 F.3d 355 (D.C. Cir. 2002) (deferential review; requires rational, not scientific, evaluation)
- Lead Industries Ass’n v. EPA, 647 F.2d 1130 (D.C. Cir. 1980) (margin of safety as a policy judgment left to the Administrator)
- American Farm Bureau Federation v. EPA, 559 F.3d 512 (D.C. Cir. 2009) (secondary standard must specify requisite level of protection; not merely compare to primary)
- Ethyl Corp. v. EPA, 541 F.2d 1 (D.C. Cir. 1976) (reasonableness in interpreting evidence and agency deference)