The United States Environmental Protection Agency (EPA) has issued a final rule that provides that a source of air pollution or an enforcement agency may use any "credible evidence" to show whether a source has complied with regulations under the federal Clean Air Act. While the rule authorizes sources to use a variety of evidence to prove compliance with federal air regulations, it has generated controversy because it also expands the scope of evidence enforcement agencies may use to prove noncompliance. The rule is relevant to any source subject to federal requirements, such as new source performance standards and national emission standards for hazardous air pollutants. This rule also clarifies that any credible evidence may be used to support compliance certifications required under Title V of the Clean Air Act, which governs the Renewable Operating Permit program.
Previously, EPA regulations had been interpreted to authorize the use of data generated only through the performance of EPA-approved reference tests to prove or disprove compliance. Such evidence is used by sources of air pollution to prove compliance with applicable air regulations and by enforcement agencies to prove noncompliance. In response to concerns raised during public comments on the rule, EPA emphasized that, while various forms of credible evidence may be used to prove compliance with applicable requirements, sources will not be expected to collect additional data to support reference test data unless information exists that contradicts the reference test data.
"[T]his regulation merely removes what some have construed to be a regulatory bar to the admission of non-reference test data to prove a violation of an emission standard, no matter how credible and probative those data are that a violation has occurred."
EPA also emphasizes that the final rule "does not amend existing emission standards nor does it modify generic regulations affecting the compliance obligation such as exceptions for startup, shutdown, and malfunctions. . . . What compliance obligation is imposed by any given emission standard remains an issue ultimately to be determined based on that emission standard and not this rulemaking." On the basis of this assumption, EPA states, the agency does not view the final rule as affecting whether a source must demonstrate intermittent or continuous compliance with applicable regulations. EPA also states, however, that its position "continues to be that an emission standard requires continuous compliance unless the emission standard specifically provides otherwise."
62 Federal Register 8314 (Feb. 24, 1997).
This article was written by S. Lee Johnson, an associate in our Environmental Law Department, and previously appeared in the May 1997 edition of the Michigan Environmental Compliance Update, our monthly newsletter published by M. Lee Smith Publishers.