December 6, 2011
The U.S. Environmental Protection Agency has strongly criticized Pennsylvania’s new policy guidelines for regulating air pollutants emitted by Marcellus Shale gas wells and development sites located in close proximity to one another. The EPA is taking the position that the Pennsylvania Department of Environmental Protection (DEP) October 12 draft policy differs from established federal law and PA’s own air pollution control plan by imposing new limitations on the aggregation of air emissions from multiple shale gas industry sources such as gas wells, compressor pumping stations and pipelines. That PA DEP policy uses the physical distance of one quarter mile between the shale gas facilities as a major qualifying criteria for determining if they should be considered as individual minor sources or a single, major source of air pollutants. In its November 21 agency comment letter, the EPA asserts that the federal Clean Air Act requires a broader geographic policy of aggregation, which may result in multiple gas development activities being treated as a single major source, and thereby requiring them to meet stricter emissions standards to prevent deterioration of existing air quality. The DEP’s “bright-line test” of one quarter mile as defining proximity was viewed positively by the natural gas industry as it provides some certainty and predictability for development. Environmental groups, on the other hand, opposed the rule on the grounds that regional air quality could ultimately degrade as a result of multiple gas industry sources of air pollution.
This presents an interesting issue of federal/state tension with respect to enforcement of environmental laws. Under the Clean Air Act, a policy of “cooperative federalism” is generally followed, which leaves it largely up to the states to implement measures to fulfill the ambient air quality standards prescribed by the EPA. The EPA is taking the position through comments in the DEP proceeding that the DEP policy is deficient in failing to account for the aggregate impact of multiple sources of pollutants. Ultimately, however, DEP has the primary responsibility for implementing the Clean Air Act within Pennsylvania, and it remains to be seen whether EPA will elevate the debate to raise a fundamental challenge to DEP’s delegated authority.