## Facts

- California’s South Coast Air Basin had some of the worst air quality in the United States and lacked adequate plans to attain national standards for ozone and carbon monoxide.
- Under the Clean Air Act (CAA), when the EPA disapproves a state implementation plan (SIP), the EPA has a mandatory duty to promulgate a federal implementation plan (FIP) within the statutory period unless the deficiency is corrected.
- In 1988, California submitted SIPs for the South Coast; the EPA found them inadequate and disapproved them.
- After the disapproval, Coalition for Clean Air and the Sierra Club (Coalition) filed a citizen suit in federal district court to compel the EPA to carry out its nondiscretionary duty to promulgate FIPs for the South Coast.
- In 1989, the EPA and California entered into a settlement agreement requiring the EPA to prepare, propose, and promulgate final FIPs for the South Coast.
- While the settlement was in place, Congress considered amendments to the CAA. The EPA sought congressional relief from its FIP obligation.
- Congress enacted the Clean Air Act Amendments of 1990, but retained the statutory requirement that the EPA promulgate a FIP when it disapproves a SIP.
- In 1991, the EPA moved in district court to vacate the settlement, arguing the 1990 amendments’ new attainment schedules and requirements showed Congress did not intend the EPA to proceed with FIPs for the South Coast based on the earlier (1988) disapproval.
- The district court agreed with the EPA, vacated the settlement agreement, and reasoned that forcing the EPA to promulgate FIPs for the South Coast would conflict with the amended statutory scheme.
- The Coalition appealed the vacatur order to the United States Court of Appeals for the Ninth Circuit.

## Issues

1. Did the Clean Air Act Amendments of 1990 eliminate or suspend the EPA’s mandatory duty—triggered by the EPA’s 1988 disapproval of California’s South Coast SIPs—to promulgate FIPs, such that the district court properly vacated the 1989 settlement requiring those FIPs?

## Decision

- The Ninth Circuit reversed the district court’s order vacating the settlement agreement.
- The court held that the 1990 amendments did not extinguish the EPA’s duty under the CAA to promulgate FIPs after disapproving California’s SIPs for the South Coast.
- Because the EPA’s obligation remained in force, the settlement agreement rested on a valid statutory duty and should not have been set aside on the theory that Congress changed the law to remove that duty.

## Legal Principles

- When Congress uses mandatory language such as “shall” in the CAA, the EPA has a nondiscretionary duty enforceable through a citizen suit when statutory preconditions are met (here, SIP disapproval and failure to cure the deficiency).
- Statutory interpretation begins with the statutory text; where the text is clear, courts generally do not rewrite the statute based on policy arguments or contested readings of legislative history.
- Amendments to a statute do not retroactively erase duties already triggered by prior agency action absent clear congressional direction.
- The CAA’s FIP provision continues to apply “whenever” the EPA disapproves a SIP; the 1990 amendments retained this structure even while adding new classifications and deadlines for nonattainment areas.
- A district court should not vacate a settlement grounded in a statutory command based on an asserted change in law where the amended statute continues to impose the same mandatory obligation.

## Conclusion

Coalition for Clean Air v. Environmental Protection Agency held that the Clean Air Act Amendments of 1990 did not relieve the EPA of its mandatory duty, triggered by the EPA’s 1988 disapproval of California’s South Coast SIPs, to promulgate federal implementation plans; the Ninth Circuit therefore reversed the district court’s order vacating a settlement that required the EPA to issue those FIPs.


Coalition for Clean Air v. Environmental Protection Agency, 971 F.2d 219 (1992)