3.2.2. Risk Assessment and Environmental Impact Assessment Environmental impact assessment (EIA) has been a mainstay of modern U.S. environmentalism. It attempts to provide procedural guarantees that ensure that a broad range of potential impacts of specified activities are identified before those activities are permitted to proceed. In general, EIA is designed to provide an assurance that knowledge of potential consequences of projected activities will be made available to decision makers or placed on the record so that interested parties can better evaluate them. Such EIA exercises tend not to be rigorously quantitative and are generally not legally tied substantatively to an decision process, though there is a procedural requirement that the assessment be carried out and publicized. Environmental risk assessment, on the other hand, is an attempt at undertaking a quantitative evaluation, with assumptions and calculations available for examination. In health risk assessment, an agreed-upon risk standard, achieved through a standardized computational formula associated with the subsequent decision, is used by governments and other decision makers as a threshold for decision based on the effect of a chemical or an action on human health. Ecological risk assessment is in an earlier stage of development. Ecological risk assessment does not enjoy the relative simplicity of health risk assessment, in which the calculation is simplified by the fact that there is one target organism (humans), and clearly specified endpoints (e.g., cancer, teratogenicity, neurotoxicity). Ecological risk assessment must deal with a broad set of endpoints and processes in a rigorous, quantifiable, and reproducible fashion, in the context of subsequent use of such information by interested parties, and a formal understanding that the outcome of the analysis may serve as an input to a subsequent decision-making process.
