What does a repository look like?

Two repositories are planned in Switzerland – one for high-level waste and one for low- and intermediate-level waste. The principle is the same for both: the waste is disposed of in tunnels or caverns located hundreds of metres beneath the earth’s surface, where it is surrounded by multiple safety barriers consisting of the waste container, the tunnel or cavern backfill material and an impermeable host rock formation. This barrier system isolates the radioactive substances from the human environment on the long term.

During the time when the waste is being emplaced in the repository, surface facilities with traffic/transport infrastructure will be required. The waste is delivered, unloaded and then transported to the underground disposal level via a ramp or shaft. High-level waste is also transferred from transport casks into disposal containers in an encapsulation plant in the surface facility. Low- and intermediate-level waste is delivered in a form that is already suitable for disposal.

Layout of a repository for high-level waste. (Image: Infel AG, C. Köppel)