U.S. EPA Proposal for Greenhouse Gas Clean Air Act Regulation

A presentation by U.S. EPA Administrator Lisa Jackson outlines an approach to regulate greenhouse gas (GHG) emissions from mobile emission sources while also laying the groundwork for exempting small industrial sources of GHG emissions.  At the center of the approach is U.S. EPA’s response to the Supreme Court’s decision that GHG from mobile emission sources could endanger public welfare (Massachusetts v. U.S. EPA).  Although the U.S. EPA response only addresses GHG emissions from mobile sources, it is establishing a precedent that will logically lead to regulation of other sources of GHG emissions under Clean Air Act (CAA) programs (e.g., New Source Review (NSR)).  The potential regulation of other sources of GHG emissions (i.e., industrial sources) is of significant concern because of the relatively low thresholds associated with defining a source as major (100 to 250 tons per year) under NSR and thus requiring regulation of that source.  U.S. EPA is proposing to address the low emission thresholds by providing precedent from previous CAA regulations involving mobile sources.  Specifically, U.S. EPA has exercised authority to regulate those sources that it felt were contributing to an air quality problem regardless of the emission threshold of the source.  U.S. EPA believes that the precedent exercised when regulating small mobile sources also establishes the discretionary review that U.S. EPA would need to exempt smaller sources of GHG under CAA programs such as NSR.  The U.S. EPA approach is most likely a stopgap measure for regulating GHGs.  There are so many aspects to GHG regulation under different U.S. EPA programs (e.g., CAA, Safe Drinking Water Act, etc.) that separate Congressional action is likely the best solution to establishing a program to provide effective management of GHGs.