Federal Court Vacates EPA’s 1994 Rule Exempting Startup/Shutdown/Malfunction Events from Clean Air Act Section 112 Compliance

January 13, 2009

Generally, pollution control technology and emissions units do not achieve 100% efficiency when turned on or turned off. Just as one must wait for the oven temperature to reach the correct cooking temperature before baking, an incinerator used to destroy toxins will not be at working temperature immediately when turned on. Thus, the U.S. Environmental Protection Agency (“EPA”) has historically exempted emission units from complying with emission standards during startup, shutdown and malfunction (“SSM”) events. See, e.g., 42 Fed. Reg. 57,125 (Nov. 1, 1977) (exempting new source performance standards’ compliance during startup/shutdown and malfunctions events). When EPA adopted its 1994 regulations creating General Provisions for National Emission Standards for Hazardous Air Pollutants under Section 112 of the Clean Air Act, it similarly exempted each source subject to an air toxic Maximum Achievable Control Technology (“MACT”) standard from compliance during SSM events, but it required the source owner subject to a MACT standard to develop an SSM plan to ensure that the source would use reasonable efforts to minimize emissions during SSM events. When EPA enacted its air operating permit program under Title V of the Clean Air Act, it required such SSM plans to be incorporated by reference into a source’s Title V permit. These provisions were not challenged.

From 2002 through 2006, EPA then made changes to the General Provisions such that the SSM plan no longer had to be incorporated by reference in the Title V permit. It then became more difficult for the public to review such plans, and it was no longer clear whether sources even had to comply with such plans. The Sierra Club therefore sued EPA over the changes made to the General Provisions after 2002.

On December 19, 2008, in a two-to-one opinion, the U.S. Court of Appeals for the District of Columbia Circuit issued a decision in favor of Sierra Club’s petition. However, instead of vacating the changes to the General Provisions that occurred from 2002 through 2006, the D.C. Circuit vacated the entire SSM exemption from the 1994 rule. Sierra Club v. Environmental Protection Agency, Case No. 02-1145 (D.C. Cir. 2008). The D.C. Circuit found that EPA’s decision to make it more difficult for the public to obtain access to SSM plans and to make complying with the SSM plans effectively optional was a sufficiently fundamental change that it “reopened” and permitted judicial review of EPA’s 1994 exemption from MACT during SSM events.

Section 112 of the Clean Air Act directs EPA to establish MACT standards, defined as standards that are “not less stringent than the emission control that is achieved in practice by the best controlled similar source” (see 42 U.S.C. § 7412(d)(3)), suggesting that EPA has discretion to recognize that today’s technology cannot achieve certain emission rates during startup or shutdown. However, the D.C. Circuit focused on the definition of “emission standard” in Section 302(k) of the Clean Air Act, defined as a requirement “which limits the quantity, rate, or concentration of emissions of air pollutants on a continuous basis, including any requirement relating to the operation or maintenance of a source to assure continuous emission reduction….” See 42 U.S.C. § 7602(k) (emphasis added). In a dissenting opinion, Justice Randolph contended that the D.C. Circuit should have found that it did not have jurisdiction because petitioners did not challenge EPA’s 1994 rule within the required 60-day period under 42 U.S.C. § 7607(b)(1). He also concluded that EPA was not provided an opportunity to address the merits of the Section 112 argument, which neither side to the case had fully briefed.

The rather drastic remedy of the majority to vacate the SSM exemption in EPA’s Section 112 General Provisions rule is perplexing because the majority appears to acknowledge the technological limitations of control equipment during startup/shutdown events. Indeed, there is no discussion in the decision on how sources can expect to comply during SSM events when technology will likely not achieve 100 percent efficiency during startup or shutdown. Moreover, many environmental programs require that sources maintain best management plans on site that are not part of an operating permit (i.e., spill prevention control plans, risk management plans, stormwater best management practices) and thus having SSM plans off-permit is certainly not unusual. By vacating the SSM exemption, sources will likely not be able to achieve “continuous” compliance each year because startup and shutdown events are part of a source’s normal operations. It will thus be important for affected sources to follow EPA’s response to the decision, including whether EPA files a motion for rehearing with the D.C. Circuit. Otherwise, EPA might need to reopen the promulgated MACT standards to establish startup and shutdown emission rates for different source categories, a very complicated process since such emission rates will depend on the control device used and its make/model. Sources might also need to work with the state permitting authorities to have emission limits created for startup and shutdown events incorporated into Title V permits.

The decision can be found at the following link:

Questions regarding this advisory should be addressed to Christine A. Fazio (212-238-8754,, Stephen L. Kass (212-238-8801, or Judith Wallace (212-238-8743,

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