## Facts

- The Sanitary Board of the City of Charleston, West Virginia operates a public wastewater treatment plant that discharges into the Kanawha River and sought a less stringent copper discharge limit to avoid costly upgrades during NPDES permit renewal.
- Under the Clean Water Act (CWA), states adopt and revise water quality standards, but EPA must review revisions and approve or disapprove them.
- West Virginia revised its copper water quality standard for the Kanawha River using the water-effect ratio (WER) method and submitted the revision to EPA on June 25, 2015.
- EPA evaluated the revision using the Biotic Ligand Model (BLM), a method EPA viewed as more comprehensive for assessing copper toxicity.
- Based on the BLM analysis, EPA concluded the revised standard was not sufficiently protective of aquatic life and issued a formal disapproval.
- The Sanitary Board sued under the Administrative Procedure Act (APA), alleging EPA’s disapproval was arbitrary and capricious; the district court entered judgment for EPA on the merits of the remaining claims.
- The Sanitary Board appealed to the Fourth Circuit.

## Issues

1. Whether EPA’s disapproval of West Virginia’s revised copper water quality standard was arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law under the APA.
2. Whether EPA properly exercised its oversight authority under CWA § 303(c) in rejecting the state’s WER-based standard based on EPA’s scientific evaluation.

## Decision

- The Fourth Circuit affirmed the judgment for EPA.
- The court held that EPA’s disapproval was supported by the administrative record and was not arbitrary or capricious under the APA.
- The court accepted EPA’s explanation that the WER-derived criterion, as applied by the state, allowed too much copper and would not protect aquatic life as the CWA requires.
- The court held EPA permissibly relied on its scientific expertise in using the BLM and in explaining why that analysis warranted disapproval of the proposed standard.

## Legal Principles

- Under the APA, a court will not substitute its judgment for the agency’s and will uphold agency action if the agency examined relevant data and gave a reasoned explanation connecting the facts found to the choice made.
- In technical and scientific matters within EPA’s delegated responsibilities, courts give substantial deference to EPA’s expert judgments when adequately explained and grounded in the record.
- CWA § 303(c) gives EPA authority to review and disapprove state water quality standards that do not meet federal requirements, including protection of designated uses such as aquatic life.
- EPA may disapprove a state standard when the state’s chosen methodology or application does not produce a scientifically justified, adequately protective criterion.

## Conclusion

The Fourth Circuit upheld EPA’s disapproval of West Virginia’s revised copper standard for the Kanawha River, concluding that EPA acted within its CWA oversight role and provided a reasoned, record-supported scientific explanation sufficient to satisfy deferential APA review.


Sanitary Bd. of Charleston v. Wheeler, 918 F.3d 324 (4th Cir. 2019)