EPA Reinstates Title V Emergency Affirmative Defense Provision

The Emergency AD rule restores the regulatory text to both 40 C.F.R. § 70.6(g) (state operating permit programs) and 40 C.F.R. § 71.6(g) (the federal operating permit program), as those provisions existed before EPA removed them in a 2023 rulemaking. 

Background and the DC Circuit Decision

On July 21, 2023, EPA issued a final rule entitled “Removal of Title V Emergency Affirmative Defense Provisions From State Operating Permit Programs and Federal Operating Permit Program” (88 FR 47029), which rescinded the emergency affirmative defense provisions that had been codified for decades at 40 C.F.R. §§ 70.6(g) and 71.6(g). The 2023 rule required states to remove analogous provisions from their own operating permit programs and from existing state-issued Title V operating permits. 

On September 5, 2025, the US Court of Appeals for the DC Circuit issued its decision in SSM Litigation Group v. EPA, invalidating the 2023 rule, finding that it rested on erroneous legal justifications. EPA’s Emergency AD rule implements the court’s mandate to withdraw the invalidated 2023 rule and restore the prior regulatory text.

The Reinstated Provision

The reinstated provision at 40 C.F.R. § 70.6(g) (and its parallel at § 71.6(g)) provides an affirmative defense to enforcement actions for noncompliance with technology-based emission limitations under a Title V permit when the noncompliance is caused by an “emergency.” An “emergency” is defined as “any situation arising from sudden and reasonably unforeseeable events beyond the control of the source, including acts of God, which situation requires immediate corrective action to restore normal operation, and that causes the source to exceed a technology-based emission limitation under the permit, due to unavoidable increases in emissions attributable to the emergency.”

Notably, EPA’s rulemaking does not revise or otherwise add to the prior regulatory language. It serves simply to reinstate this affirmative defense as it previously existed prior to the 2023 rule. 

Relationship to the SSM SIP Call Decision

The Emergency AD rule is limited to the Title V emergency affirmative defense provision and does not address the separate, but related, recent DC Circuit decision addressing EPA’s removal of startup, shutdown, and malfunction (SSM) provisions from state rules. In Environmental Committee of the Florida Electric Power Coordinating Group, Inc. v. EPA, 94 F.4th 77 (D.C. Cir. 2024), the DC Circuit vacated the bulk of EPA’s 2015 “SIP Call” (80 FR 33840), which had required states to remove SSM provisions from their State Implementation Plans (SIP). 

Following the Florida Electric Power decision, EPA issued guidance in December 2024, clarifying how the agency intends to evaluate SIP submittals in light of the vacatur.

EPA’s Emergency AD rule and its guidance on SSM provisions signals a broader judicial and regulatory recalibration back to how emissions and compliance obligations were previously handled under the Clean Air Act during upset conditions and startup and shutdown periods.

Illinois Implications

Illinois law previously contained a substantively analogous emergency affirmative defense provision at 415 ILCS 5/39.5(7)(k), which required that “[e]ach CAAPP permit shall include an emergency provision providing an affirmative defense of emergency to an action brought for noncompliance with technology based emission limitations.” This provision was removed from the Illinois statute following EPA’s 2023 rulemaking. With EPA’s reinstatement of the federal provision today, the question now becomes whether Illinois will restore its own statutory emergency affirmative defense and, if so, on what timeline. 

Separately, on the SIP side, Illinois revised its SIP in response to EPA’s 2015 SSM SIP Call by repealing its startup, malfunction, and breakdown provisions (formerly codified at 35 Ill. Admin. Code Part 201, Subpart I). Despite the DC Circuit’s vacatur of much of the 2015 SIP Call in Florida Electric Power, Illinois has not reinstated those provisions.