Analysis of Environmental Impact Statements Shows Widely Varying Treatment of Climate Change Risks

By Patrick Woolsey, CCCL Intern

U.S. Government agencies have begun to incorporate consideration of climate change and greenhouse gas emissions into the environmental impact statements (EISs) which they are required to produce under the National Environmental Policy Act (NEPA). However, federal agencies have developed widely varying procedures for addressing the topic. The Center for Climate Change Law (CCCL) has prepared a comprehensive database of 196 EISs that substantively address climate change-related impacts, covering the period from January 1, 2009 through November 1, 2011. The database records the state, lead agency, and type of project, and discusses and categorizes the climate change-related impacts considered in each EIS. While most federal agencies now address climate change to some extent in EIS preparation, the specific impacts considered and the methodology used in analysis vary greatly between agencies.
The database prepared by CCCL identifies several major categories of environmental impacts related to climate change, and records which categories are discussed in each EIS. These categories for analysis of climate change impacts are based on those proposed by CCCL Director Michael Gerrard in a 2008 article. The database includes all EISs prepared during the period which substantively address at least one of the impact categories, which include the following:

  • Direct operational impacts: This category includes smokestack greenhouse gas emissions from power plants, heating emissions from buildings, emissions from mining and drilling processes, and emissions resulting from impacts on carbon sinks such as forests, soils, and agricultural lands.
  • Purchased electricity: This category includes greenhouse gases emitted in generating the electricity that is produced off-site and purchased by the facility.
  • Induced trips: This category encompasses vehicle and transit emissions from any trips resulting from project construction and operation, the transport of freight to and from the project.
  • Construction impacts: This category covers emissions from extracting and fabricating the construction materials, and from the equipment used at the construction site.
  • Impact of climate change on the project: This category includes the effects of rising sea levels and water tables, increased flooding, extreme weather events, greater temperature variations, water shortages, and activities needed to adapt to climate changes.

The Center for Climate Change Law has also produced a matrix which summarizes overall patterns in EIS preparation by various federal agencies. For each agency, the matrix lists the number of environmental impact statements produced in the given period which covered each of the impact categories described above. The matrix also includes agency-wide comments on the impact scope and methodology generally used in EIS preparation. These comments qualitatively address the following three questions:

  • Were greenhouse gas emissions quantified using project-specific calculations, estimated using generic figures, or simply described in qualitative terms?
  • Did the EIS include a complete life-cycle analysis of direct and indirect emissions, ranging from the impacts of resource extraction, transport, construction or processing, and final use?
  • Did consideration of impacts of climate change include only discussion of local climate impacts on the project or a consideration of cumulative regional or national impacts of climate change?

A comparison of agency approaches to EIS scope and methodology shows widely varying treatment of these issues. While some agencies exhaustively calculate emissions using specific figures, others provide only very general estimates or conclude that emissions are not significant enough to warrant calculation. Some agencies include indirect impacts such as purchased electricity and induced trips, but many others do not. Discussion of the impacts of climate change also varies greatly. While some EISs emphasize scientific uncertainty about the scope and nature of future climate impacts, others provide projections of potential long-term impacts at the national, regional and project level.

Future blog posts will discuss these findings in detail, and will draw distinctions based on agency, project type, methodology, and climate impacts considered.