36th Technical Meeting of the Mont Terri Project

The 36th Technical Meeting of the Mont Terri Project was held in Switzerland on the 5th and 6th of February 2019. Rebecca Newson attended from Quintessa. At the meeting, updates were given regarding ongoing and proposed experiments at the Mont Terri rock laboratory. The meeting was followed by a day of invited technical discussions on the FS-B (Fault Slip), CS-D (Carbon Storage) and FE (Full Emplacement) experiments

The Mont Terri rock laboratory is run by swisstopo, and 19 international partners are involved with experiments at the site. These experiments are designed to research the feasibility of geological disposal of radioactive waste and carbon storage by investigating the hydrogeological, geochemical and mechanical characteristics of the host Opalinus Clay formation, and of various engineered barrier systems. The laboratory is currently undergoing extension to make room for new experiments.

Quintessa has provided support to Nagra by modelling the FE (Full Emplacement) experiment at Mont Terri. This experiment is designed to represent the Swiss concept for disposal of spent fuel and high-level waste at full scale. Quintessa developed THM models of the experiment in QPAC to make blind predictions of the long-term temperature evolution in the rock. The experiment is still ongoing, and the most recent data presented at the Technical Meeting showed that current behaviour is consistent with Quintessa’s predictions.

Quintessa has also had involvement with the Mont Terri Project through DECOVALEX (DEvelopment of COupled models and their VALidation against EXPeriments). Various phases of DECOVALEX have looked at the VE (Ventilation Experiment), HE-D and HE-E heater tests, FS (Fault Slip) and EB (Engineered Barrier) experiments. Some Mont Terri experiments may be considered for modelling tasks in the next phase of DECOVALEX.