Radioactive waste is already transported today, for example when bringing spent fuel assemblies from nuclear power plants to an interim storage facility by rail or road. Eventually, all waste will have to be transported from the interim storage facilities to the surface facility of the deep geological repository in Stadel. The protection of humans and the environment has the highest priority when transporting radioactive waste. Legal requirements are strict, with each transport requiring a separate permit.
Disposal canisters undergo very thorough tests
The transport and storage casks for high-level waste and spent fuel assemblies must pass stringent tests, including, for example, being dropped from a height of nine metres onto an unyielding foundation, or being exposed to a 30-minute fire test at an average flame temperature of at least 800 degrees Celsius.
Impressive demonstration: Castor containers put to the test
The concrete containers for low- and intermediate-level waste are also subject to national and international norms and regulations. To demonstrate their suitability for transport, they are subjected to a drop test, and calculations are made. For the drop tests (see photo), containers weighing up to 25 tonnes are dropped onto a steel plate. The containers have to withstand this fall without any leakage of content and without any impairment to the shielding effect of the concrete.
In Switzerland and many other countries, radioactive waste has been transported by rail and road for decades. The infrastructure, technology and experience required for transporting radioactive substances are thus already in place.
How the waste is transported to Stadel
Radioactive waste is not disposed of where it is produced. It is first taken to an interim storage facility, from where it will eventually be transported to the deep geological repository in Stadel.
To transport the waste from the interim storage facility in Würenlingen to the repository in Stadel, Nagra favours uninterrupted transport by road.
This option has several advantages.
- Simpler logistics: truck transports consist of the three steps “loading”, “driving” and “unloading”. This means fewer handling and shunting steps than by rail.
- Road transports also allow more flexibility: they do not have to take rail schedules into account. Several routes are available for these transports.
- Transport by rail is more complicated and costly yet offers no benefits.
While rail transport is possible in principle, it would require the construction of loading stations. There would also be two additional loading processes because neither the interim storage facility in Würenlingen nor the surface facility in Haberstal are directly connected to the railway network. Accordingly, the first and last stretches of the route would have to be covered by truck.
Final transport route yet to be determined
Nagra will not specify a particular transport route until the construction licence has been granted. It will then choose the option that is the most sensible at that time, meaning that transportation via rail still remains an option.
