Recent Development in Clean Air Act Regulation – Affirmative Defenses



In the matter of Env’t Comm. of the Fla. Elec. Power Coordinating Grp. v. EPA, D.C. Cir., No. 15-1239, decided on March 1, 2024, the US Court of Appeals for the D.C. Circuit held that the USEPA cannot require states to revise their State Implementation Plans (SIPs) to remove automatic exemptions (for pollution released during startups, shutdowns, and malfunctions (SSMs)), director’s discretion provisions, and affirmative defenses that are functionally exemptions. The Court held that the United States Environmental Protection Agency (USEPA or EPA) exceeded its statutory authority in calling for the removal of exemptions without demonstrating that the exemptions materially impede compliance with Clean Air Act requirements.

As is reflected in the decision, the Clean Air Act statutory framework requires that the federal government and the states work together to protect air quality. First, the EPA identifies pollutants that endanger public health and welfare and sets air-quality standards that the states must meet. Then, the states develop State Implementation Plans (SIPs) to meet and enforce those standards. EPA must ensure that the SIPs comply with specific requirements that the Clean Air Act imposes for SIPs, and must call for the state to revise their SIP if the SIP is substantially inadequate to comply with a requirement of the Act.

In a prior decision, NRDC v. USEPA, 749 F. 3d 1055 (2014), the Court held that emergency affirmative defense provisions interfered with the Court’s authority to decide on the penalty of a violator and the EPA’s and the public’s ability to seek injunctive relief and monetary penalties against sources that violate SIPs’ emission rules, contrary to 42 U.S.C. §§ 7604(a), 7413(b). As a result of the Courts decision, USEPA adopted rules on July 21, 2024, removing the Title V Emergency Affirmative Defense provisions. Thereafter, EPA called for states to revise their SIP accordingly.

Now, in Env’t Comm. of the Fla. Elec. Power Coordinating Grp. v. EPA, D.C. Cir., No. 15-1239 (2024), the Court has clarified its finding further and has restated a States’ discretion under the Clean Air Act (42 U.S.C. § 7410(a)(2)(A)) to determine what enforceable emission limitations and other control measures are necessary or appropriate to meet the Acts requirements. In its ruling, the Court held that the EPA didn’t sufficiently consider whether some of the emissions provisions could be seen as “other control measures”—which might not require continuous application, and are thus allowable and adequate to achieve compliance with the Act.

Per the Court, EPA needed to determine that it is “necessary or appropriate” that the restrictions be continuous to enable the state to “meet the Clean Air Acts applicable requirements.” 42 U.S.C. § 7410(a)(2)(A). That, the Court concluded, it did not do. On this basis, the Court reviewed and upheld automatic exemptions, director’s discretion provisions, and affirmative defenses that are functionally exemptions in State Implementation Plans, while finding that enforcement-discretion provisions and other affirmative defenses remain with the Court. The Court found that EPA can still take action if it can demonstrate that specific SSM exemptions in SIPs materially impede compliance with CAA requirements, such as preventing a state from meeting national air quality standards.

Diane Alexander has advised public and private sector clients regarding local government, environmental, infrastructure and resiliency-related issues and has successfully litigated matters involving a wide variety of environmental laws and regulations.

Ms. Alexander represents public authorities, municipalities and the private sector concerning water, wastewater, stormwater and air permitting issues, as well as water and wastewater planning, compliance, user fee and connection fee issues.  She participated in the Stakeholders Group convened by the New Jersey Department of Environmental Protection to revise the NJPDES Regulations, Planning Rules and Surface Water Quality Standards. She participated in the drafting of legislation relevant to connection fees and the creation of stormwater utilities.  Ms. Alexander’s Martindale-Hubbell Peer Review Rating is AV® Preeminent.

Ms. Alexander also served a five year term on the Board of Directors of the Association of Environmental Authorities of New Jersey.

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