Probabilistic seismic hazard assessment for two potential nuclear power plant sites in Tunisia

As part of a feasibility study for a potential electronuclear power plant in Tunisia, a new seismic catalogue and a new seismic source model have been proposed, for Tunisia and adjacent areas. These findings are used in this study to evaluate the seismic hazard for two selected nuclear power plant sites: Marsa-Douiba in the north and Skhira in the southeast. The investigations and the assessment are conducted at a regional scale. The location of these sites and the choice of a regional review extent allow us to consider the entire Tunisian territory as the study area and also to conduct the hazard evaluation at a ‘national level’. In this study, a probabilistic seismic hazard analysis is performed using the R-CRISIS software, and a logic tree is developed to capture uncertainties related to the characterisation of both seismic sources and ground-motion. First, a hazard map of Tunisia for the return period of 475 years is generated to compare it with the ones obtained within previous studies. Then, the 10,000-year return period is considered, and the recommendations of the International Atomic Energy Agency are applied to determine the uniform hazard spectrums and perform disaggregation for the selected sites.