EU Flag EC FP6 Integrated Project on the Geological Disposal of Radioactive Waste

The Full-scale Engineered Barriers Experiment (FEBEX) project at the Grimsel Test Site (GTS) has been established as a large scale experiment focusing on:

  1. Demonstrating the feasibility of actually manufacturing and assembling an engineered barrier system based on the Spanish SF disposal concept for a crystalline host rock.

  2. Developing methodologies and models for assessment of the thermo-hydro-mechanical (THM) and thermo-hydro-geochemical (THG) behaviour of the engineered barrier system (near field).


As part of the FEBEX site instrumentation, Nagra took responsibility for the installation of a TDR (Time Domain Reflectometry) system for measuring the water content changes in both the bentonite backfill and the granite rock formation. The TDR system was emplaced in summer 1996; long-term monitoring of water content started immediately after sensor emplacement.

Febex TDR Monitoring

The FEBEX project formally ended in December 2004, but the in-situ work is carried on within the frame of the EC integrated NF-Pro project (cf. ).

The integrated THM (C) experiment at real scale - actually started on 1st of January 2005. A vital aspect of Nagra's involvement is, beside the further monitoring of water content changes in the bentonite buffer, the refinement of the TDR technique as a method for water content measurements in low porosity rock formations.

For more information about this project, or to get in touch, please use our contact page.


Near Field Processes (NF-PRO) Experiment Diffusion - Long Term Diffusion project (LTD)