EPA Releases Proposed Endangerment Finding on Emission of Greenhouse Gases

EPA released today its much-anticipated proposed endangerment finding for greenhouse gas (“GHG”) emissions from new motor vehicles and engines in response to the U.S. Supreme Court’s April 2, 2007, decision in Massachusetts v. EPA. The proposed finding is issued under Section 202(a)(1) of the Clean Air Act, which requires EPA to determine whether emissions from new vehicles and new vehicle engines “cause or contribute, to air pollution which may reasonably be anticipated to endanger public health or welfare.” In the proposal EPA broadly defines Section 202(a)(1) to mean that the endangerment determination may include an assessment of current and future risks rather than being limited to proof of actual harm.

The proposal defines “air pollution” to include six greenhouse gases (“GHGs”) – CO2, methane, nitrous oxide, hydrogenated fluorocarbons, perfluorocarbons and sulfur hexafluoride, although the proposal finds that only the first four are emissions from new motor vehicles and engines.

The proposal asserts that climate change will lead to (a) increases in illnesses and premature deaths and (b) increases in runoff and erosion causing adverse water quality effects. Sea-level rises will affect coastal communities and ecosystems. It also finds that elevated GHGs in the atmosphere will result in intensification of heat waves, storms, and droughts, which in turn will increase mortality and morbidity among vulnerable population groups and disease and injury due to floods, droughts and fires and that adverse health effects due to climate change will fall disproportionately on the poor, the disabled, the elderly and the uninsured.

If finalized, the endangerment finding will trigger GHG emission limitations on new vehicles and engines. However, given that similar endangerment findings serve as the bases for other programs under the Clean Air Act, it is anticipated that, unless Congress acts, EPA will also begin to regulate GHGs from stationary sources and set ambient air quality standards and new source performance standards for GHGs. Although EPA insists that it would not enforce major source permitting requirements against the many small facilities and buildings that would technically become major sources of GHG emissions, EPA cannot control how a federal court would rule in the event of a citizen’s suit to force regulation of all sources that emit GHGs in excess of the statutory thresholds.