(GRS 207) Ventilation Test at Mont Terri: Geoelectric Monitoring

This report presents information on geoelectric measurements performed by GRS during a Ventilation Experiment (VE) in the Mont Terri Underground Research Laboratory (MTURL).The VE was a joint experiment performed by four partners of the Mont Terri project. The partners were the Spanish Empresa Nacional de Residuos Radiactivos (ENRESA) as project leader, the French Institut de Radioprotection et de Sûreté Nucléaire (IRSN), the Swiss Nationale Genossenschaft für die Lagerung radioaktiver Abfälle (NAGRA) and the GRS.Within the project GRS was responsible for the investigation of desaturation and resaturation of the Opalinus clay during the ventilation of a microtunnel simulating the ventilation of a nuclear repository in a geological clay formation.