The third day of the CAS course "Working Environment Nuclear Energy" focused on legal principles, supervision, and radioactive waste disposal.
⚖️ Legal basis and supervision:
In the morning, Andreas Schefer from the Swiss Federal Nuclear Safety Inspectorate (ENSI) outlined the regulations that apply in Switzerland and how they have developed over recent decades, partly as a result of events such as Three Mile Island, Chernobyl, and 9/11. Swiss nuclear power plants are now subject to strict legal requirements, which are continuously monitored by the independent regulatory authority ENSI.
🔎 The IAEA standards and the "3S" principle (safety, security, safeguards) form the international framework for this.
🛢️ Temporary storage and disposal:
In the afternoon, Raphael Spuler (Zwilag) and Philipp Senn (Nagra) provided insights into the processing and interim storage of radioactive waste. At the central interim storage facility in Würenlingen, low- to medium-level waste (SMA), such as protective clothing, is poured into containers suitable for final disposal in a plasma furnace at temperatures of up to 20,000 °C with the addition of glass. Although the very high temperatures do not reduce the radioactivity, they do significantly reduce the volume of waste.
High-level waste (HLW), such as spent fuel elements, is stored in sealed containers – commonly referred to as "Castor containers." After loading, these containers have surface temperatures of 60-70%. Only after a decay period of around 40 years can the waste – after being repackaged into smaller sealed steel containers – be transferred to the deep repository.
⚛️ From interim storage to deep geological repository:
According to Nagra's site proposal, final disposal is to take place in the planned deep geological repository near Nördlich Lägern, where the suitable host rock, Opalinus Clay, is located several hundred meters underground.
💡 Opalinus Clay forms a natural, robust barrier for the long-term protection of future generations.
💰The deep repository is financed by the Decommissioning and Waste Management Fund (STENFO).
It was an informative day course that highlighted how much expertise, responsibility, and sustainable thinking goes into the safe disposal of radioactive waste. The peaceful use of nuclear energy in Switzerland is clearly defined by a comprehensive set of regulations and forms the legal basis for the safe operation of nuclear facilities.
🔎 Further information about CAS
CAS Working Environment Nuclear Energy | BFH
