Nagra to start a series of deep boreholes in Bülach and Trüllikon

Nagra is starting a series of deep boreholes in Bülach and Trüllikon. Construction of the drill sites will begin in the coming weeks and further boreholes in the potential siting regions Jura Ost, Nördlich Lägern and Zürich Nordost will follow later. The purpose of the boreholes is to supplement investigations that have already been carried out and thus complete the picture of the underground geological environment. Building on this additional information, Nagra will be able, in around four years, to announce the sites for which it will prepare a general licence application.

The deep boreholes in Bülach and Trüllikon are the first in a series of boreholes that Nagra plans to drill in the three potential siting regions Jura Ost, Nördlich Lägern and Zürich Nordost. Construction of the drill site in Bülach is expected to start in the coming weeks and work in Trüllikon will begin thereafter. Actual drilling activities will start at the beginning of 2019.

The investigations will include the thickness, permeability and composition of the Opalinus Clay host rock in which the repository will be constructed. The properties of the rock formations lying above and below the Opalinus Clay are also of interest. The boreholes will round out the overall geological picture of the siting regions and thus provide a scientifically well-founded basis for selecting the safest repository sites. One borehole will cost around 15 million Swiss Francs.

The boreholes will supplement the 3D seismic measurements that have already been carried out; the results of these were presented in Bülach. The measurement results show that, in principle, there is sufficient space in all three siting regions for constructing a deep geological repository.

Building on the additional information from the borehole investigations, Nagra expects to be able, in 2022, to announce the sites for which it will prepare and submit a general licence application. Nagra submitted 22 applications for drilling permits to the Federal Department of the Environment, Transport, Energy and Communications (DETEC) and a 23rd application is still to be submitted (for Nördlich Lägern). Three permits have already been granted and others are expected in the coming months. How many boreholes will actually have to be drilled to complete the geological picture will depend on the results. It is not planned to drill all 23 boreholes.

More information: Patrick Studer, Head Media Service Nagra: 076 579 36 50 patrick.studer@nagra.ch

According to Swiss nuclear energy legislation, the producers of radioactive waste are responsible for its safe management and disposal. In 1972, the Federal Government and the nuclear power plant operators set up the National Cooperative for the Disposal of Radioactive Waste (Nagra) to perform this task. Nagra, which has its headquarters in Wettingen (AG), is the national technical competence centre in the field of deep geological disposal of radioactive waste.

Out of a strong sense of responsibility for the long-term protection of man and the environment, 120 employees are involved daily in performing this important work. The high level of competence is secured by targeted research programmes in two Swiss underground rock laboratories and intensive international collaboration.

According to Swiss nuclear energy legislation, the producers of radioactive waste are responsible for its safe management and disposal. In 1972, the Federal Government and the nuclear power plant operators set up the National Cooperative for the Disposal of Radioactive Waste (Nagra) to perform this task. Nagra, which has its headquarters in Wettingen (AG), is the national technical competence centre in the field of deep geological disposal of radioactive waste.

Out of a strong sense of responsibility for the long-term protection of man and the environment, 120 employees are involved daily in performing this important work. The high level of competence is secured by targeted research programmes in two Swiss underground rock laboratories and intensive international collaboration.