## Facts

- The Clean Water Act required EPA to set nationwide effluent limitations for categories of point sources, including 1977 limits based on “best practicable control technology currently available” (BPT) and later limits based on “best available technology economically achievable” (BAT).
- Congress expressly authorized BAT variances in § 301(c) based on an individual owner/operator’s “economic capability” and “reasonable further progress” toward eliminating pollutant discharges, but did not create a comparable statutory variance provision for BPT.
- EPA promulgated BPT effluent-limitation guidelines for the coal mining industry and certain mineral mining and processing operations.
- EPA’s BPT variance regulation allowed consideration of “greater than normal cost of implementation,” but barred granting a variance solely because the applicant was economically unable to afford compliance.
- Industry groups challenged both the BPT standards and the limitation on BPT variances that excluded inability-to-pay as a basis for relief.
- The Court of Appeals for the Fourth Circuit held EPA’s variance limitation unduly restrictive and required EPA to consider additional factors, effectively including an individual discharger’s economic capability.
- The Supreme Court granted review and considered the consolidated disputes concerning the validity of EPA’s BPT variance limitation.

## Issues

1. Whether the Clean Water Act requires EPA to consider an individual discharger’s economic inability to comply when deciding variances from uniform BPT effluent limitations.
2. Whether § 301(c)’s BAT variance criteria (including “economic capability” and “reasonable further progress”) must be applied to BPT variance determinations despite the absence of a statutory BPT variance provision.

## Decision

- The Supreme Court reversed the Fourth Circuit.
- The Court held the Act does not require EPA to consider an individual operator’s economic capability (inability to pay) when deciding whether to grant a variance from uniform BPT limitations.
- The Court upheld EPA’s regulation precluding BPT variances based solely on economic inability to meet the uniform standard.
- The Court concluded the court of appeals erred by rejecting EPA’s interpretation of the statute.

## Legal Principles

- When Congress expressly provides a variance mechanism for one statutory standard (BAT under § 301(c)) but omits a comparable mechanism for another (BPT), courts should not infer a requirement to apply the omitted variance criteria to the other standard.
- BPT limitations are technology-based and category-wide; the statutory scheme emphasizes uniformity across point-source categories rather than plant-specific affordability exceptions.
- EPA may allow limited BPT variances based on factors such as “greater than normal” compliance costs without being required to grant variances grounded on an operator’s inability to pay.
- Agency interpretations of complex environmental statutes are entitled to significant judicial respect where consistent with statutory text, structure, and congressional design.

## Conclusion

The Court held that EPA’s BPT program may maintain uniform, technology-based effluent limits without requiring plant-specific inability-to-pay variances, and that the individualized economic-capability criteria Congress provided for BAT variances in § 301(c) do not govern BPT variance decisions.


Env’t Prot. Agency v. Nat’l Crushed Stone Ass’n, 449 U.S. 64 (1980)