Non-destructive assay sampling of nuclear fuel before encapsulation

Volume: 56, June 2018, pages 6-11

Authors: C. Hellesen and S. Grape

_{Division of Applied Nuclear Physics, Department of Physics and Astronomy, Uppsala University}

Abstract: Swedish spent nuclear fuel is planned to be verified before being encapsulated and placed in a geological repository 500 meters below ground in the bedrock. Verification before encapsulation is intended to ensure both the safe storage of the spent fuel, and that Sweden is honoring its international obligations according to the NPT, international treaties and bilateral agreements on the topic of nuclear safeguards.

The measurements will mark the last chance of verifying the spent fuel, as there are no plans to retrieve them once they enter the geological repository. With respect to nuclear safeguards, fuel assemblies will likely be verified for both gross defects and partial defects, whereby a fraction of the fuel content has been removed or replaced. A conclusion also needs to be made on the correctness of the fuel assembly declarations, translating into a verification (or determination) of the fuel parameters such as initial enrichment, burnup and cooling time.

Keywords: non-destructive assay; spent nuclear fuel; sampling; encapsulation

Reference guideline:

Hellesen, C., & Grape, S. (2018). Non-destructive assay sampling of nuclear fuel before encapsulation. ESARDA Bulletin - The International Journal of Nuclear Safeguards and Non-proliferation, 56, 6-11. https://doi.org/10.3011/ ESARDA.IJNSNP.2018.2