Can the rock laboratory be converted to deep geological disposal?

No. That is not possible. The rock laboratory is used only for research purposes. There can be no question of the disposal of radioactive waste here. That is part of the contractual arrangement with the Canton of Jura.


What is researched in the rock laboratory?

Research is separated into individual experiments, differentiated according to the following types: Development of methodology, e.g. test performance and related analyses; Characterisation of Opalinus Clay, e.g. understanding the chemical and physical processes in the Opalinus Clay at the laboratory and investigating the relevant properties and Parameters; Demonstration experiments. Here, tests on a 1:1 scale can be carried out over a long period. Generally, the experiments in the rock laboratory provide a significant body of knowledge about the feasibility and safety of deep geological disposal.


Why clay for a deep geological disposal facility?

Argillaceous rocks are suitable as a geological barrier for the long-term encapsulation of radioactive waste. The three most important characteristics are: Retention of radionuclides at the clay mineral surfaces, very low permeability (no transfer of radionuclides by flowing water), and the ability to self-sealing of cracks and fissures by swelling.

Properties of Opalinus clay

Is it possible to visit the rock laboratory?

Yes! Guided tours of the Mont Terri rock laboratory are organised throughout the year for groups of visitors. More information is available here: Tel. +41 32 461 40 53 /

Welcome to the visitors center

The Mont Terri project

The picture shows the entrance to the rock laboratory with the flags of all patners at the door.

The Mont Terri Project is an international research project for the hydrogeological, geochemical and geotechnical characterisation of a clay formation (Opalinus Clay).


Welcome to the Mont Terri underground rock laboratory



Following the current measures of the Canton of Jura and the Confederation, the Visitor Center is closed until further notice.

The Federal Company for Radioactive Waste Disposal BGE in Germany is a new research partner in the Mont Terri project


Since 1 July 2020, the Federal Company for Radioactive waste Disposal BGE in Germany is a new partner in the Mont Terri research project. This means that 22 organisations from nine nations are now conducting research in the Mont Terri Rock Laboratory near St-Ursanne under the direction of swisstopo. 






Start of excavation for Gallery 2018 on March 12

Start of excavation works for Gallery 2018
Responsibles from Confederation, Canton Jura and Underground Rock Laboratory (URL) during the start of the extension work

The expansion of the Mont Terri rock laboratory in St-Ursanne has officially started. In just under two years, the research facility will have an additional 600 metres of tunnels and niches for experiments.

More informations

Start of excavation for Gallery 2018

Impressions from the rock laboratory

News: Extension of the Mont Terri rock laboratory

News: Extension of the Mont Terri rock laboratory

From 2018 to 2019 the Mont Terri rock laboratory was extended. Here, you find more links and information about it.

Extension 2018

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