Environmental Impact Assessments (EIA) are interdisciplinary analyses of the natural, human health, and socio-cultural effects which are expected to result from public and private sector actions such as development projects. The purpose of these studies is to comprehensively inform decision makers and the affected public about both the proposed action and its alternatives, so that wherever possible significant negative impacts may be avoided, minimized, or mitigated.
Historically, the decades following World War II were a period of unprecedented economic development and environmental change. The rapid creation of jobs, housing, transportation, and energy systems were accompanied by widespread negative environmental transformations including air and water pollution, destruction of ecosystems, the conversion of farmlands, and major redevelopment of historic urban centers. These changes were graphically brought into homes each evening by the new medium of television.
The emergent environmental movement of the 1960s played a key role in governments enacting substantive new environmental laws. Typically, each law addressed a specific problem. For example, the U.S. Clean Air Act, and Clean Water Act were designed to regulate pollution by setting specific allowable concentration limits on lists of specific toxic chemicals in air, water, and on land. Other laws focused on such issues as wetlands, endangered species, and historic preservation. These regulatory approaches were highly effective—but necessarily quite narrow in scope. In contrast, a fundamental concept of environmental understanding and stewardship is the need for an integrated holistic approach to knowledge building and decision making.
The U.S. National Environmental Policy Act (NEPA) of 1969 was the first legislation to provide a robust framework for allowing all recognized environmental concerns to be addressed simultaneously. Of special note: the work of Lynton Caldwell was a seminal driver of United States environmental policy and legislation. He was one of the authors of NEPA. He wrote the Draft Resolution on a National Policy for the Environment that provided the theoretical foundations of NEPA. NEPA was designed to complement, not supersede, other laws and programs. It created the EIA process as a means to integrate the generation and dissemination of environmental information, and foster collaboration among the diverse set of public and private actors and stakeholders which characterize major, environmentally controversial decisions. Since its enactment, many international organizations—for example, the European Community, sovereign countries, provinces or states and local governments—have passed their own versions of environmental impact assessment legislation.
Environmental Impact Assessment Process
The most visible product of the EIA process is an Environmental Impact Statement (EIS), an often lengthy and technical document that describes and comparatively evaluates the proposal and its alternatives. It is important for citizens and interest groups interested in influencing public decisions to understand the EIS in its procedural context. In the early years of EIA, there was confusion about what constituted a proper analysis and when it was appropriate. In response to often costly and sometimes questionable studies, many EIA laws and procedures evolved a “triage” approach to efficiently and effectively focus public attention and analytical resources on issues of primary environmental concern. Figure 1, the EIA Triage Process, is a generic representation of the approach based on NEPA.
Elements of the diagram include:
Proposal- an early stage of decision making when a project's needs and objectives have been clarified but prior to major expenditures being committed. Major categories of government actions include: construction of public works, development of management plans for public lands, and issuance of permits for development.
Exclusion- each sector of government: legislature, judicial, and administrative may exclude agency actions from the process. The latter are typically repetitive minor projects such as roadway maintenance.
Environmental Assessment- a detailed examination of the proposal and its local environmental context with an emphasis on reducing/eliminating impacts through mitigation such as noise barriers or habitat restoration.
Scoping- initial meeting(s) of all available stakeholders and decision makers to determine: jurisdictions; what existing data is available; what studies need to be done (feasible alternatives and impact categories); and workload responsibilities. A lead agency, responsible for all EIS documents is designated.
Notice- public notification that an EIS is being prepared for a specific project and who to contact for further information and participation.
Draft EIS (DEIS)- preliminary document including description of the proposed action, its alternatives, (one of which is the “no action alternative”), baseline (existing environmental conditions), and comparative estimates of the major expected environmental impacts over the life of the project.
Comment- written or public hearing statements which provide substantive critiques from all participants in the study and all affected parties. The intent is to assess the adequacy of the data, alternatives, and analyses, not to have an opinion poll.
Final EIS (FEIS)- the DEIS, plus responses to all substantive issues raised in the comment period, including additional studies undertaken. In the FEIS, the lead agency identifies its preferred alternative, if this had not been in the DEIS.
Record of Decision- the formal public decision of the lead agency accompanied by a brief justification based on agency law, available resources, and the information generated in the EIA process.
Although EIAs are now widely used, a number of significant issues regarding the process and outcomes exist. These include: public confusion, questions regarding our ability to predict futures, the cost and environmental effectiveness of the process, and the role of the Internet in collaborative decision making.
By definition, the EIA process is an information policy not a substantive regulatory one such as a pollution law. Publics are often confused as to why, after participating (providing data, making comments), in an EIS analysis that concludes negative impacts will occur, a decision is made to proceed. Public information regarding who makes the decisions and how they will make them is typically lacking at the start of the EIA process.
Our ability to predict the future behavior of complex environmental systems is quite limited. In contrast, following the lead of pollution laws and permits, the impact forecasts and projections in most EISs include numerical tables, graphs, and maps that do not state (through error bars, ranges, map zones, etc.) the quality of information provided to publics and decision makers. Scientists, environmentalists, and decision makers have deep distrust of the artificially precise presentations of many EISs.
The actual physical and socio-economic outcomes which result from the EIA process are poorly understood. Most program evaluations have focused on document outputs, such as the contents of the EIS, rather than studying the actual short- and long-term outdoor environment. In particular, serious questions remain regarding the implementation and effectiveness of impact mitigation, such as creating new habitat, which is frequently called for in the EIS. Unlike substantive regulations, the EIA process typically does not include monitoring or enforcement.
EIA is an information process whose origins and decision framework preceded the Internet. Although there are many recent isolated examples of information technology use, the full potential of a transparent distance-collaborative decision process has not yet emerged. Access to data, interactive modeling, exchange of comments during the draft review, and adaptation of 3-D and motion visualization hold the promise of major transformaition.