Supporting the site selection process of a deep geological repository

Understanding and quantifying the uncertainty and its sources is essential for sound decision-making.
The siting regions Jura Ost, Nördlich Lägern and Zürich Nordost were investigated as candidates constructing a deep geological repository.
Project overview

We supported Nagra in the site selection process for a deep geological repository. To this end, we enhanced an existing probabilistic model to evaluate the impact of erosion on the safety of the repository within the next one million years in order to identify the most suitable siting region.

Even though tremendous efforts and resources have been invested for data acquisition and model building, predicting the remaining cover above the repository a million years in the future inevitably involves considerable uncertainties.

Eracons deliverables

Eracons investigated if further model enhancements and additional data could potentially lead to a change in the recommendation and in this way identified the most influential uncertain parameters in the model. We advised Nagra on what information is required to improve the robustness of the decision process. By gradually refining and improving the employed probabilistic modeling approach in sensitive parts, we could show that a change in the optimal siting region in light of additional information is highly unlikely.