## Facts

- Quivira Mining Co. and Homestake Mining Co. operated uranium mining and milling facilities near Grants, New Mexico.
- EPA issued Clean Water Act NPDES permits for pollutant discharges from:
  - Quivira’s Ambrosia Lake facility into Arroyo del Puerto.
  - Quivira’s Lee Mines into San Mateo Creek.
  - Homestake’s facility into Arroyo del Puerto.
- The companies challenged EPA jurisdiction, asserting Arroyo del Puerto and San Mateo Creek were intermittent/ephemeral features and not “waters of the United States.”
- An adjudicatory administrative hearing developed a record including technical evidence on hydrology and downstream connectivity.
- The EPA Administrator denied further agency review in written orders, making the permits final agency action.
- The companies petitioned the Tenth Circuit for review.

## Issues

1. Whether the court should review EPA’s “waters of the United States” determinations de novo as “jurisdictional facts,” or instead apply substantial-evidence review to the Administrator’s factfinding from an adjudicatory record.
2. Whether Arroyo del Puerto and San Mateo Creek qualify as “waters of the United States” subject to Clean Water Act regulation and the NPDES permit program.

## Decision

- The court applied substantial-evidence review to the EPA Administrator’s factual determinations, rejecting de novo review based on a “jurisdictional fact” label.
- The court denied the petitions for review and affirmed EPA’s issuance of the permits.
- The court upheld EPA’s determinations that Arroyo del Puerto and San Mateo Creek are “waters of the United States” because the administrative record supported findings of tributary status and hydrologic connection to downstream waters.
- Certiorari was denied, leaving the judgment in place.

## Legal Principles

- In judicial review of final EPA action based on an adjudicatory record, agency factfinding is upheld if supported by substantial evidence, including on factual questions that bear on statutory coverage.
- “Waters of the United States” under the Clean Water Act may include non-navigable tributaries, including intermittent or ephemeral streams, when record evidence shows a sufficient hydrologic connection such that discharges can affect downstream navigable waters.
- EPA may regulate discharges to upstream tributary features where substantial evidence supports a finding that pollutants can move through the drainage system to protected downstream waters.

## Conclusion

The Tenth Circuit upheld EPA’s NPDES permitting authority over discharges to two intermittent New Mexico watercourses, deferring to the Administrator’s technical factfinding and concluding that substantial evidence supported classifying the arroyos as “waters of the United States” under the Clean Water Act.


Quivira Mining Co. v. U.S. EPA, 765 F.2d 126 (10th Cir. 1985), cert. denied, 474 U.S. 1055 (1986)