Obama Administration Declares Greenhouse Gases Endanger Public Health

The Environmental Protection Agency April 17 issued a proposed rule declaring that greenhouse gases endanger public health and welfare, a move that lays the groundwork for the agency to begin regulating emissions linked to global warming.

"Concentrations of greenhouse gases are at unprecedented levels compared to the recent and distant past. These high atmospheric levels are the unambiguous result of human emissions, and are very likely the cause of the observed increase in average temperatures and other climatic changes," EPA said.

EPA is undertaking the proposed rulemaking under Section 202 of the Clean Air Act in response to a 2007 Supreme Court ruling related to emissions from motor vehicles. The court said greenhouse gases are pollutants under the Clean Air Act and that the agency must either issue an endangerment finding or justify a decision not to (Massachusetts v. EPA, 127 S. Ct. 1438, 63 ERC 2057 (2007)).

Administrator Lisa Jackson signed the proposed rule April 17, and the agency said it would appear in the Federal Register soon. EPA will take comment on the proposed rule for 60 days after it is published.

"This finding confirms that greenhouse gas pollution is a serious problem now and for future generations. Fortunately, it follows President Obama's call for a low carbon economy and strong leadership in Congress on clean energy and climate legislation," Jackson said in a statement. "This pollution problem has a solution—one that will create millions of green jobs and end our country's dependence on foreign oil."

A final rule finding that greenhouse gases endanger health and welfare would lead to regulation of greenhouse gas emissions from motor vehicles under the Clean Air Act, and indirectly to regulation of greenhouse gas emissions from stationary sources.

EPA cautioned that the finding in itself does not impose any requirements. The agency would have to conduct further rulemaking to impose regulatory requirements on motor vehicles or stationary sources of greenhouse gas emissions. Before taking any steps to reduce greenhouse gases under the Clean Air Act, EPA would conduct an appropriate process and consider stakeholder input, the agency said.

In announcing the proposed rule, EPA noted that both Obama and Jackson have repeatedly indicated a preference for comprehensive legislation from Congress to address the issue and create the framework for a clean energy economy.

Sen. Barbara Boxer (D-Calif.), chairman of the Senate Environment and Public Works Committee, also stated a preference for having Congress act.

The EPA proposed finding identified six key greenhouse gases that the agency said threaten public health and welfare: carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride.

The proposed rule outlined two key findings: first, that greenhouse gases are pose a danger, and, second, that the combined emissions of carbon dioxide, methane, nitrous oxide, and hydrofluorocarbons from new motor vehicles and motor vehicle engines contribute to the atmospheric concentrations of the gases and to the threat of climate change.

Under Section 202 (a) (1) of the Clean Air Act, EPA must issue standards for air pollutants from new motor vehicles or new motor vehicle engines that cause or contribute to air pollution "which may reasonably be anticipated to endanger public health or welfare."

Before issuing any standards to regulate emissions, the agency must first determine whether the pollutant may reasonably be anticipated to endanger public health or welfare. Second, EPA must decide whether emissions from new motor vehicles or engines cause or contribute to the pollution.