A novel non-destructive assay methodology for the disposal of the LHC beam dumping system at CERN

During the Long Shut-down (LS2), the beam stopper of the Large Hadron Collider (LHC) was replaced. It was decided to eliminate the extracted two LHC beam dumps, also known as Target Dump for Ejected Beam External (TDE), as radioactive waste. The radiological characterization of the dumps is a vital and a necessary step for the proper classification and subsequent acceptance by the radioactive waste repository. The acceptance criteria require accurate declaration of the activity values of the Easy-to-Measure (ETM) radionuclides. This paper provides an overview of the challenges related to the high contact dose rates (reaching 2 mSv/h) and the heterogeneous distribution of the ETM radionuclides. This work proposes a novel quantification methodology that addresses those challenges. The developed methodologies followed can serve as a guide for addressing similar challenges in other accelerator and nuclear facilities.