EPA Considering Change to “Upset” Emissions Exemptions

May 31, 2012

In a November 2011 consent decree, the EPA agreed to issue a final decision by August 31, 2012, in consideration of Sierra Club’s petition to prohibit states from allowing SIPs to exempt “upset” and other emissions during SSM periods under NAAQS. The decree states that granting of the petition shall be considered a “SIP Call.” Under the Clean Air Act, the EPA must initiate a SIP call “whenever the Administrator finds that the applicable implementation plan for an area is substantially inadequate to attain or maintain the relevant national ambient air quality standards.” If the EPA initiates a SIP Call, it could face legal opposition to its demonstration of meeting the statutory requirement for a SIP Call.

In June 2011, the Sierra Club submitted a petition to the EPA requesting that EPA find substantially inadequate and correct 39 state implementation plans (SIPs) that contain startup, shutdown, and malfunction (SSM) emission exemptions under the national ambient air quality standards (NAAQS). Granting of the petition would require states with SIPs containing SSM exemptions to revise their SIPs in conformity with the Clean Air Act or otherwise remedy these defective SIPs. Additionally, the petition asks for the EPA to rescind policies “allowing states to adopt affirmative defenses to excess emissions.”

The Clean Air Act requires that SIPs ensure states’ attainment of NAAQS, but in many states, SSM emissions are exempt from enforcement of emission level standards. SSM emissions can significantly surpass emission limits in SIPs due to limitations in facility control technologies that may not function sufficiently during SSM periods. The petition states that “SSM exemptions undermine the emission limits in SIPs and threaten states’ abilities to achieve and maintain compliance with NAAQS, thereby threatening public health and public welfare, which includes agriculture, historic properties and natural areas.”

Without SIPs SSM emissions exemptions, companies that emit above the allowable levels during SSM periods could face civil penalties. Facilities that would be prone to liability if SSM emission exemptions are eliminated can take active steps to prepare and reduce SSM emissions by installing pollution control technology equipment such as a baghouse.