The U.S. Environmental Protection Agency has issued a proposed finding  that greenhouse gases contribute to air pollution that may endanger public health or welfare. The announcement Friday is likely the first step to new EPA regulations relating to greenhouse gas emissions (“GGE”) under the Clean Air Act.

            The proposed endangerment finding identified six greenhouse gases, including carbon dioxide and methane, that have been linked to climate change. “In both magnitude and probability, climate change is an enormous problem. The greenhouse gases that are responsible for it endanger public health and welfare within the meaning of the Clean Air Act,” the EPA said.

            The proposed finding now enters a 60-day public comment period, which is the next step the EPA must undertake before issuing a final decision. The  proposed finding does not include any proposed regulations, but could lead to EPA regulations or serve as a springboard for comprehensive legislation in this area as proposed by President Obama.

            This step by the EPA raises an interesting question of the interrelationship of potential federal GGE regulation and California GGE regulations that are already being crafted under such statutes as AB 32 and SB 375.

            Some federal law allows parallel or more stringent state regulation – for example, the federal Endangered Species Act and the federal Clean Water Act.  Other federal legislation preempts state legislation, either by legislative fiat or judicial interpretation. 

            The Clean Air Act, for instance, has been a fertile field for litigation relating to federal preemption. In a December 2008 decision, the Bush EPA denied California’s request for a waiver to enforce more stringent auto emission standards.  Last fall, a federal court overturned that decision, and the Obama EPA has since indicated its intent to support California’s efforts in this area.  Whether this position will allow California’s comprehensive GGE policy to continue in force in its current form will likely be vetted through the EPA’s stakeholder process.