Trial Run of SNF Disposal Facility to Start in 2023

Onkalo, Finland’s geological repository for spent nuclear fuel, will conduct a full-scale trial run disposing spent fuel in 2023. The trial run involves the entire disposal process using systems and equipment for disposal, but without spent fuel. It will be replaced with dummy fuel assemblies.

Main stages of the SNF trial run disposal:

  1. Dummy spent fuel bundles are transported from interim storage to the encapsulation plant.
  2. The copper canisters are loaded with dummy nuclear fuel bundles and then sealed by welding.
  3. The filled copper canisters are hoisted down to the repository area and are inserted into the deposition holes.
  4. Demonstration tunnel is backfilled and closed with a plug.
  5. A “damaged” canister is hoisted up to mitigate the damage and return to normal operation.

The trial run of the Onkalo spent fuel disposal facility in Finland is the final stage before the operation, which is scheduled to start by 2025. Posiva will be the first organization to build a geological repository for spent fuel. The disposal process consists of placing twelve fuel assemblies in a special canister and sealing it in a copper capsule. Each capsule is then placed in a separate hole in the branch of the storage and filled with bentonite.

According to Posiva