Groundwater diversion from a deep-rock repository for spent nuclear fuel: Ecohydrological assessment of environmental impacts

¹ EmpTec, Larmvägen 8, SE-187 75 Täby, Sweden
² Ekologigruppen AB, Åsögatan 121, SE-116 24 Stockholm, Sweden
³ Swedish Nuclear Fuel and Waste Management Co, Box 250, SE-101 24 Stockholm, Sweden

Abstract

Forsmark in Mideastern Sweden is chosen as site for the planned Swedish deep-rock repository for spent nuclear fuel. The construction, operation and decommissioning of the repository require assessments of various types of risks for health and environment on a wide range of temporal scales. This study is focused on the assessment of environmental impacts during the relatively short construction and operation phases, during which the repository will be kept drained by means of groundwater diversion. This diversion may influence hydrogeological and hydrological conditions and thereby cause ecological and other types of consequences in the surroundings of the repository. We here describe methodology and some main findings from the ecohydrological assessment of consequences for aquatic and terrestrial ecosystems in Forsmark. The assessment combines the results of a number of steps, including ecological field inventories and predictive water-flow modelling. The results of the study show that subsurface disposal of radioactive waste is an important application of ecohydrological concepts in assessments of sites with nature values.