Deep borehole campaign: Nagra’s next borehole will be in Stadel instead of Eglisau

Nagra completed the borehole in Bülach at the of 2019. Contrary to the original plan, however, the next borehole to be drilled in the Nördlich Lägern siting region will be the Stadel-3 borehole.

Nagra decided to drill the second borehole in the Nördlich Lägern siting region, Stadel-3, to the north of the community of Stadel. “As part of our more detailed planning for the Eglisau borehole, we analysed the results of the 3D seismic measurements in detail. We came to the conclusion that the borehole is feasible, but is more challenging than we expected”, explains Markus Fritschi, member of Nagra’s Executive Board. It has become clear that the Stadel geology is more representative for the Nördlich Lägern siting region than that of Eglisau. This is important for the deep borehole campaign because, while all of the rock samples Nagra obtained in Bülach were of good quality, for technical reasons some tests to be conducted directly in the borehole could not be performed. Nagra will now conduct these tests in the Stadel borehole.

For these reasons, Nagra has decided to drill the next borehole, Stadel-3, to the north of the community territory at Hasliboden. Construction of the drill site is expected to begin in the spring of 2020, and drilling will not start before the following autumn. If required, drilling in Eglisau will be conducted at a later date.

The purpose of the deep boreholes is to determine which of the three regions Jura Ost, Nördlich Lägern and Zürich Nordost is best suited for the construction of a deep geological repository. The lead in the search for a site lies with the Federal Government.

Nagra has submitted a total of 23 permit applications for deep boreholes in the three siting regions. How many boreholes will actually be drilled to complete the overall picture of the underground geological environment depends on the results, but it is not planned to drill all 23 boreholes. Nagra has set up a hotline for questions and concerns of local residents and other interested persons. It is free and operates 24/7 (0800 437 333). The drill sites also have a visitors’ pavilion and regular open days for the public.

More information: Patrick Studer, Head, Media Office: 076 579 36 50.

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.