Its all very well to design a waste disposal system - but how do you know that it will work ?
This is where the Grimsel Test Site (GTS) comes in - with experiments to test the long term behaviour of the engineered barriers, to develop and test tools to confirm the suitability of potential geological host rocks and to test the models used to predict its performance as a long-term barrier to radionuclide release.
Many countries have plans for repositories but in order to ensure that their designs will work, they need somewhere to test out their concepts for safe waste disposal.
These tests should be carried out in similar conditions to a repository. The GTS is a research facility several hundred metres underground which provides a relevant environment for equipment, methodology and model tests.
The GTS is a scientific test site and not a potential repository site; although investigations may utilise a wide range of radioactive tracers, no radioactive waste will be disposed of at the GTS.
All experiments utilising a radioactive tracer are supervised by a Radiation Protection Expert (RPE) and follow very strict regulations which were set by HSK (Hauptabteilung für die Sicherheit der Kernanlagen / Swiss Federal Nuclear Safety Inspectorate - now ENSI ) and continues with BAG (Bundesamt für Gesundheit / Swiss Federal Office of Public Health).
Nagra's high level waste (HLW) disposal concept - cutaway. View The Engineered Barrier System section