The database prepared by the CCCL identifies five major categories of environmental impacts related to climate change that are discussed in EISs, and includes all EISs prepared during the period that substantively addresses at least one of the five impact categories. The categories for analysis of climate-change impacts are based on those proposed by CCCL director Michael Gerrard (Climate Change and the Environmental Impact Review Process, Natural Resources & Environment, pages 20–24 (Winder 2008)), and include the following:
- Direct operational impacts. 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. Greenhouse gases emitted in generating the electricity that is produced offsite and purchased by the facility.
- Induced trips. Vehicle and transit emissions from any trips resulting from project construction and operation; the transport of freight to and from the project.
- Construction impacts. Emissions from extracting and fabricating the construction materials, and from the equipment used at the construction site.
- Impact of climate change on the project. 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.
A comparison of agency approaches to EIS scope and methodology shows widely varying treatment of these impact categories. While some federal agencies include indirect impacts such as purchased electricity and induced trips, many others do not. Few EISs include a complete life-cycle analysis of direct and indirect emissions, ranging from the embodied emissions in materials used, resource extraction, and transport to construction, processing, and final use.
More than three-quarters of EISs address direct operational emissions, often from a stationary project facility. Smokestack greenhouse-gas emissions from power plants, emissions from the combustion of heating fuel for buildings, and emissions from mining and drilling processes are usually quantified. Direct impacts are rarely addressed in EISs for land management. Emissions resulting from impacts on carbon sinks such as forests, soils, and agricultural lands are often not discussed, and are rarely quantified if they are discussed. However, in many EISs that address fishery management, agriculture, forestry, and parks and wildlife, direct emissions may not be applicable or significant.
Emissions from purchased electricity are considered most frequently in EISs for buildings and real estate. Some EISs for electric-powered public rail-transportation projects consider purchased electricity, and some note that power used would come from renewable sources, but others do not address the issue. Renewable power-generation projects often consider the potential emissions offset that could be created if the power they supply to the grid displaces existing fossil-fueled power generation or reduces the need for additional generating capacity.
Emissions from induced trips are usually considered in highway and public transportation EISs, which analyze project impacts on traffic patterns and vehicle miles traveled. They are also sometimes addressed in EISs involving large buildings or developments that generate significant traffic. EISs for renewable-power-generation facilities sometimes consider induced trips to the site by maintenance vehicles. Mining EISs and fossil-fueled power-plant projects also sometimes consider emissions from the transport of coal by trucks or rail.
Construction impacts are frequently considered in EISs for buildings, renewable-power-generation facilities, public infrastructure, pipelines, and power-transmission lines. Surprisingly, highway and public-transit EISs consider construction impacts less often. When construction impacts are addressed, they typically consider only the emissions from the operation of construction vehicles, and not the emissions embodied in the materials used or their transport to the site.
Discussion of the impacts of climate change also varies greatly. While some EISs assert that scientific uncertainty about the scope and nature of future climate impacts makes analysis impossible, others provide projections of potential long-term impacts on the project site. More than one-third of the EISs considered address impacts of climate change on the project. The effects of climate change are most likely to be considered in EISs for coastal or water-related projects such as irrigation systems and reservoirs, ports, bridges, and waterfront development, as well as military installations and land-management or forestry projects. EISs for coastal projects address the impacts of sea-level rise and increased storm intensity on vulnerable infrastructure, while EISs for water-supply projects, forestry, parks, and wildlife address the impacts of climate change on freshwater resources, natural ecosystems, and specific plant and animal species. EISs for nuclear-generating facilities also often consider the vulnerability of the reactor to climate-change impacts, especially the availability of freshwater resources used to supply the plant’s cooling systems.
Federal agencies also differ in the methodology used to analyze climate-change impacts and alternatives. Many EISs make reference to the methods described in the CEQ guidance as well as any relevant directives from the preparing agency and from state government. However, some agencies exhaustively calculate emissions using project-specific figures, while others provide only generic estimates or conclude that emissions are not significant enough to warrant calculation. While some EISs include detailed analysis of the impacts of several alternatives to the proposed project, this typically includes only a qualitative comparison of the emissions levels from alternatives, when the issue is addressed at all. However, a few EISs include tables that calculate estimated emissions from each alternative and present them for comparison. Renewable energy projects often evaluate their emissions relative to fossil-fueled alternatives, but the reverse is not true—EISs for coal-fired-power-generating stations rarely address renewable energy as a potential alternative.
The degree to which EISs address climate change is closely tied to the preparing agency. While most agencies cite the nonbinding CEQ draft guidance, it gives them considerable discretion to decide when analysis of climate impacts is warranted and how the significance of climate impacts is determined. Certain federal agencies tend to produce more EISs that address climate change in substantial detail, such as the U.S. Army Corps of Engineers, the Department of Energy, the Bureau of Land Management, and the Bureau of Reclamation. However, it is difficult to make comparisons across agencies and project types, given the very different criteria and needs that are addressed in EISs for federal decisions involving everything from fishery management to power generation.
The extent to which climate impacts are analyzed in EISs also corresponds to the type of project, and to the state in which the project is located. EISs are most likely to consider climate impacts on solar power, coastal, or water-supply projects, because the future viability of these projects is often closely tied to the effects of climate change, adaptation, and resilience. However, this is not always the case, as EISs for some other project types that are closely related to issues of greenhouse-gas emissions, such as agricultural or public-transit projects, include very little analysis of climate change. Climate-change impacts are often considered more extensively in EISs prepared in states such as California and Washington, which have robust state environmental-review laws. Federal agencies often partner with state agencies for these projects and produce EISs that go beyond the federal requirements.
The CCCL’s research reveals inconsistent treatment of climate-change impacts in federal EISs, with significant variation correlating with state, agency, and project type. Agencies differ in the methods used to calculate emissions and assess their significance, the types of indirect impacts addressed, and the extent to which the impacts of climate change on the project are included. Although the treatment of climate change in environmental-impact assessment is still in the early stages of development, a general trend is evident in most federal agencies toward more frequent and more comprehensive analysis of project impacts on climate change and the impacts of climate change on federal actions.
The CCCL’s database of EISs, along with a collection of federal, state, and international protocols for climate change analysis in the environmental impact review process, isavailable online.
Keywords: environmental litigation, Center for Climate Change Law, environmental impact statement, NEPA, National Environmental Policy Act, Council on Environmental Quality
Patrick Woolsey is an intern at the Center for Climate Change Law at Columbia University.