AiNT and Mirion Technologies (Canberra) are jointly developing a waste drum measurement system called “Advanced Sectorial Gamma Scanning” (ASGS) for the characterization of radioactive waste. The innovative measurement and analysis method is capable of reconstructing the radionuclide activity within the drum with spatial resolution. In combination with the analysis software “ECIAD” (Efficiency Calculation for Inhomognious Activity Distributions), the measurement uncertainty can be significantly reduced compared to Segmented Gamma Scanning (SGS) without compromising on measurement time.

The safe management requires adherence to strict regulations during the conditioning, packaging and characterization of radioactive waste. The non-destructive assay by measuring the gamma-emitting isotopes has proven to be an efficient method in determining the radioactive inventory of waste with respect to dose uptake, time and cost. The method of SGS has been applied for decades, however, the technique relies on simplifying assumptions. These result in higher measurement uncertainties which in consequence leads to a declaration of high ‘virtual activity’ of conservative estimates.

• Measurement of non-homogeneously distributed activity inventories
• Determination of nuclide-specific activity with lower measurement uncertainty than in SGS
• Reduced virtual activities in the waste declaration
• Uncertainty calculation according to DIN ISO 11929
• High dynamic range for activity contents
• High throughput due to large collimator aperture-opening
• Adaptable to varying waste drum sizes