ENSI’s assessment of earthquake safety at the Beznau nuclear power plant ruled correctly

The press release of the Federal Administrative Court:

The Swiss Federal Nuclear Safety Inspectorate assessed the earthquake safety of the Beznau nuclear power plant in accordance with the legal requirements. The Swiss Federal Administrative Court has thus rejected an appeal lodged by 15 individuals.

Following the nuclear disaster at Fukushima in March 2011, the Swiss Federal Nuclear Safety Inspectorate (ENSI) requested that Axpo Power Ltd. verify the earthquake safety of the Beznau nuclear power plant. The operator had to prove that the plant could cope with an earthquake of a magnitude encountered once every 10`000 years and that radiation exposure in the vicinity of the plant would not exceed 100 millisieverts. In July 2012, ENSI found that the operator had provided the required proof of safety at the plant and thus saw no reason to decommission it provisionally with immediate effect.

Case brought by 15 individuals

In April 2017, 15 individuals appealed to the Swiss Federal Administrative Court (FAC) against ENSI’s ruling made at the beginning of 2017 regarding the safety evidence. In particular, they challenged the radiation exposure dose limit of 100 millisieverts stipulated by the inspectorate. They believed that this should be set at a level of one millisievert for an earthquake of a magnitude occurring once every 10`000 years. Since this lower limit value would be exceeded in an event of this kind, they claimed that keeping the Beznau nuclear power plant operating would be illegal and demanded it to be decommissioned immediately for the time being.

Assessment of the Federal Administrative Court

Following an interpretation of the relevant standards, the FAC has concluded that ENSI was correct in setting the permissible radiation exposure limit at 100 millisieverts for an earthquake of a magnitude occurring once every 10`000 years. It also ruled that it was not obliged to consider any further, less frequent earthquakes in its assessment either and that the dose of radiation had been calculated correctly. The court has accordingly dismissed the appeal.

This judgment may be appealed to the Federal Supreme Court.