The Federal Waster Pollution Control Act (FWPCA),¹ which doubtless contains the most intricate of all congressional directives governing the establishment of pollution control standards, is also one of the least fathomable of the federal environmental laws. Naturally, the Act's ambiguities and omissions have led to extensive litigation that has interfered with its implementation. A case in point concerns the role of compliance costs in applying nationwide effluent limitations.

With respect to the effluent limitations requiring point sources to apply the best available technology by the mid-1980s,² the Act clearly authorizes variances to be granted to any source owner in order to relieve it of undue economic hardship. Yet with respect to the effluent limitations requiring application of the best practicable control technology by 1977,³ the statute makes no mention of variances. The United States Supreme Court ruled in 1977 that such variances are implicitly available,⁴ but it did not address whether they should issue to relieve economic hardship. Nor has Congress chosen to address the matter. A split among the circuits on the question disrupted the Environmental Protection Agency's (EPA's) efforts to promulgate nationally applicable, industry-by-industry effluent limitations and moved the Supreme Court to resolve the issue.