Uncertainty in EIA

Environmental Impact Assessment (EIA) is focused on assessing possible future impacts of development proposals, and can be viewed as a risk assessment tool, incorporating uncertainty into decision-making. Uncertainty can also be seen as an inherent part of assessing projects ex ante. Uncertainty can be described generally, and specifically in EIA, e.g., via its sources such as an uncertain project design or uncertain data. Studies have described various tools for handling uncertainty, e.g., adaptive management and scenarios. Despite possible sources of and tools for uncertainty in EIA, studies have shown lacking disclosure and handling of uncertainty in EIA. This chapters reviews recent literature on EIA uncertainty and discusses the role and choices for actors in EIA concerning uncertainty. Some of the key points emerging is the discretion of actors, and the need for knowledge concerning roles and choices, as well as the need for a common language concerning uncertainty in EIA.