On April 11, the U.S. Court of Appeals for the District of Columbia Circuit vacated the

Environmental Protection Agency’s December 18, 2008 CERCLA/EPCRA Administrative Reporting Exemption for Air Releases of Hazardous Substances from Animal Waste at Farms rule (Rule) that created hazardous substance reporting exemptions for all farms, except large animal raising operations known as concentrated animal feeding operations (CAFO). The case is Waterkeeper Alliance, et al. v. EPA. The case was argued in December 2016, or almost eight years after the rule was promulgated.

The Rule amended Environmental Response, Compensation, and Liability Act of 1980’s (CERCLA) hazardous substance notification requirements, and the Emergency Planning and Community Right-to-Know Act of 1986’s (EPCRA) emergency release notification rules. The Rule exempted from the law’s notification requirements any releases of hazardous substances into the air from farms, while the EPCRA rule exempted such releases of hazardous substances for decomposing animal waste, unless the farming facility can be classified as a “CAFO,” based on the large number of animals being raised in confined conditions.

The challenges to the Rule stressed the fact that decomposing animal waste can generate two specific hazardous substances—ammonia and hydrogen sulfide—and the statutes do not permit EPA to grant reporting exemptions for releases above the regulatory reportable quantity. EPA argued in response that such reports are unnecessary because “in most cases, a federal response is impractical and unlikely,” and that it had an implied de minimis authority to create certain categorical exemptions “when the burdens of regulation yield a gain or trivial or no value.”

The Court of Appeals notes that this de minimis authority was recognized by the DC Circuit several years ago in the case of Alabama Power v. Costle. Here, however, the Court of Appeals holds that EPA’s reasoning was unreasonable under both the Chevron approach and the Supreme Court’s recent pronouncements in Utility Air Regulatory Group v. EPA, and struck it down. It reasoned that reports of such releases can have real value to EPA and other regulatory bodies and, moreover, EPA has broad regulatory powers under CERCLA to develop an adequate response.