May 23, 2001

The Environmental Protection Agency's Request for Comment on a Petition - Control of Emissions From New and In-use Highway Vehicles and Engines

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EPA’s request for comment on a petition: Control of Emissions from New and In-Use Highway Vehicles and Engines

Stated Purpose:

EPA requests public comment on a petition to regulate emissions of carbon dioxide (CO2), methane (CH4), nitrous oxide (N20), and hydrofluorocarbons (HFCs) from new motor vehicles and engines under section 202(a)(1) of the Clean Air Act (CAA or Act).

Summary of RSP Comment:

The International Center for Technology Assessment's (CTA) petition requesting that EPA regulate certain greenhouse gas emissions should be denied for the following reasons:

  • Legal controversy exists over whether greenhouse gases are air pollutants as defined by Section 202(1) of the CAA. Although the EPA General Counsel opined that CO2 fits the definition of an air pollutant in a 1998 memorandum, efforts to regulate CO2 and greenhouse gases defy the explicit wishes of Congress.
  • The evidence regarding global warming and human contribution to it is mixed, and as forecasts of anthropogenic warming get more refined, they predict less extreme warming.
  • Petitioners do not argue that greenhouse gas emissions directly endanger public health and welfare, but rather that, by increasing global temperatures they will indirectly have negative effects. There is little, if any, scientific support for dire predictions that warming temperatures will result in rampant tropical diseases etc. On the contrary, if a slight warming does occur, historical evidence suggests it is likely to be beneficial, occurring at night, in the winter, and at the poles. Taking "precautionary action" to protect human health based on a series of tenuous linkages would likely create a new set of risks.
  • It is not in the public interest to undermine the expressed will of our elected officials, who have repeatedly examined the question of whether to regulate these gases as air pollutants and chosen not to.