A risk science perspective on the treatment of uncertainty in EIAs: An illustrative case from Norwegian EIA regulation

Uncertainty is a central issue in environmental impact assessments (EIAs), as these assessments aim to predict future environmental consequences of proposed actions and development projects. Assessment, characterization, and management of such uncertainties have been discussed extensively in the literature on EIAs. Yet, calls are made for further work and improvements: There is a need for common terminology, principles and frameworks across specialized fields and applications. The present paper aims to contribute to this end by providing a risk science perspective on the understanding and treatment of uncertainties in EIAs. This perspective provides generic knowledge on concepts, principles, approaches, models and methods for assessing, characterizing, communicating and handling risk and uncertainties. An EIA can be seen as a study of future consequences and associated uncertainties, which in risk science captures the essential features of the risk concept. Following this logic, we analyze and illustrate how EIA can be seen as a special case of risk assessment. By considering the Norwegian EIA regulation, as well as key Norwegian EIA guidelines, we further demonstrate how different aspects of EIAs can be strengthened by adopting this perspective, including conceptual clarity and understanding. The paper concludes that integrating risk science concepts into established EIA practice is not straightforward, but further work on this integration can enhance both the EIA and risk fields.