In Switzerland, the largest producers of radioactive waste are the nuclear power plants (NPPs). Other sources are applications in medicine, industry and research. All waste emplaced in the repository will be required to conform with waste acceptance criteria. The corresponding radionuclide inventory, the waste packages, masses, and volumes are included in the MIRAM (Model Inventory of Radioactive Materials) database for the general licence application (Nagra 2023b).

Five types of waste will be disposed of in the HLW repository section: two types of RP-HLW and three types of SF. RP-HLW contains most of the fission products from the spent fuel assemblies reprocessed at La Hague, France and at Sellafield, United Kingdom. During the production of this reprocessed waste, the liquid glass is poured into cylindrical steel moulds, which are then sealed. After cooling, the glass forms a homogeneous waste matrix. Spent fuel (SF) consists of fuel assemblies removed from Swiss NPPs and, to much lesser extent, from research reactors. The numbers of canisters for each waste type are presented in Tab. ‎5‑1.

Tab. ‎5‑1:HLW types and the numbers of canisters for each type

* Considered together with the pressurised water reactor SF without MOX in the analysis of radiological consequences.

Alpha-toxic waste (ATW) and low- and intermediate-level waste are disposed of in the L/ILW repository section. Both cover a broad spectrum of radioactive waste. ATW comprises (see Tab. ‎5‑2):

• waste from the reprocessing of spent fuel assemblies (structural parts of reprocessed fuel assemblies and waste from the operation of reprocessing plants), and

• operational waste from research facilities, especially PSI and CERN, and various wastes from medicine and industry.

L/ILW (see Tab. ‎5‑2) comprises:

• operational waste from the NPPs (resins, concentrates, sludges, mixed waste), the ZWILAG interim storage facility and the encapsulation plants for the deep geological repository,

• reactor waste from NPPs (mainly activated, replaceable reactor components),

• decommissioning waste from the NPPs (activated and contaminated reactor and building components and secondary waste arising during conditioning of the decommissioning waste), the interim storage facility and the encapsulation plants for the deep geological repository, and

• operational and decommissioning waste from research facilities, in particular PSI and CERN, and various wastes from medicine and industry.

ATW and L/ILW both consist of metallic, organic and inorganic materials, which are generally conditioned prior to interim storage.

Tab. ‎5‑2:L/ILW types and the numbers of waste packages for each type