Interim storage as a step within waste management

These are those of ZWILAG Zwischenlager Würenlingen AG in Würenlingen in the Aargau canton as well as the federal interim storage at the same location. The ZWILAG interim storage company was founded by the nuclear power plant operators and its storage can accept all waste categories.

The ZWILAG central interim storage facility. In the building with semicircle roof construction are the administration and conditioning systems. To the left of this is the storage for decommissioning waste, crosswise the hall for low and medium-level waste, and at the front in the middle the hall for high-level waste. In the building to the right of this is the plasma system and on the far right the Federal interim storage. Source: ZWILAG

The high level radioactive waste is located either in interim storage at the nuclear power plants or in the ZWILAG interim storage. The low and intermediate level waste from the nuclear power plants is also accepted at the ZWILAG interim storage. The low and intermediate level decommissioning waste – until it can be placed into geological deep repository – is stored in the ZWILAG interim storage halls. The low and intermediate level waste from medical, industrial and research applications are stored in the federal interim storage.

The storage capacity of ZWILAG and the various storage deposits at the nuclear power plants is sufficient for the operation and decommissioning of the existing nuclear power plants in Switzerland, even for an operational life of more than 50 years.

The evidence of suitability for geological deep repository of the waste packages is part of the approval of the waste package type. The first storage of waste packages of a type and all storage of transport- and storage containers with spent fuel rods or high level radioactive waste in an interim storage require permission from the regulatory authority.

Interim storage facilities for radioactive waste must be designed such that the capability of the waste packages for geological deep storage is not compromised and sufficient storage capacity for the foreseeable requirements is available.

This ensures that the waste packages can be placed in interim storage without compromising their properties relevant to further waste disposal steps.

Source: Federal department of the Environment, Transport, Energy and Communication DETEC, Swiss Federal Office of Energy SFOE; Interim storage factsheet.