## Facts

- EPA proposed a sulfur oxide emissions regulation for Deer Lodge County, Montana, as part of a federal implementation plan under Clean Air Act § 110(c).
- Anaconda operated a copper smelter that was the only significant sulfur oxide source in the county, making the general regulation effectively applicable only to Anaconda.
- Anaconda claimed the proposed emissions limit was technologically and economically infeasible and could cause other environmental harms (including water pollution).
- Anaconda demanded an adjudicatory, trial-type hearing with subpoena and cross-examination rights; EPA declined but held a public hearing and accepted Anaconda’s written submissions and supporting material.
- Anaconda asserted EPA could not proceed without preparing an Environmental Impact Statement (EIS) under NEPA.
- Anaconda sued in federal district court seeking to enjoin EPA from proceeding unless EPA prepared an EIS and provided an adjudicatory hearing; the district court granted declaratory and injunctive relief.
- EPA appealed.

## Issues

1. Whether the district court had jurisdiction, and whether the dispute was ripe, to enjoin ongoing EPA rulemaking before final promulgation of a Clean Air Act § 110(c) regulation.
2. Whether NEPA required EPA to prepare an EIS before proposing or promulgating a Clean Air Act § 110(c) implementation plan regulation.
3. Whether the Clean Air Act required EPA to provide a trial-type adjudicatory hearing (including subpoenas and cross-examination) before proceeding with the proposed regulation.

## Decision

- The court of appeals reversed the district court and vacated the injunction.
- The district court lacked jurisdiction to halt ongoing rulemaking, and the challenge was not ripe because the regulation had not been finally promulgated; the Clean Air Act channels review of such actions to the courts of appeals after final agency action.
- NEPA did not require EPA to prepare an EIS as a precondition to proposing or promulgating the implementation plan regulation.
- EPA was not required to provide Anaconda a trial-type adjudicatory hearing; the Clean Air Act’s “public hearing” requirement contemplated informal, legislative-type procedures.

## Legal Principles

- Where Congress provides a specific statutory review path for agency action (including direct review in the courts of appeals), district courts generally may not intervene to enjoin ongoing rulemaking outside that scheme.
- Pre-promulgation challenges to nonfinal agency proposals are ordinarily unripe when meaningful judicial review is available after final agency action.
- NEPA’s EIS requirement does not necessarily apply to EPA regulatory actions taken under the Clean Air Act when imposing an EIS would conflict with or impede the agency’s statutory mission to protect environmental quality.
- A statutory requirement for “public hearings,” without “on the record” language or comparable triggers, supports informal rulemaking procedures rather than formal adjudication with subpoena and cross-examination rights.
- Rulemaking that is policy-oriented and generally applicable remains legislative in character even if, as a practical matter, a single regulated entity is chiefly affected.

## Conclusion

The Tenth Circuit held that the Clean Air Act’s review structure and finality limits barred district court interference with EPA’s ongoing § 110(c) rulemaking, and it further ruled that EPA could proceed without preparing a NEPA EIS or providing Anaconda a trial-type adjudicatory hearing, so long as required public participation procedures were afforded.


Anaconda Co. v. Ruckelshaus, 482 F.2d 1301 (10th Cir. 1973)