Large quantities of decommissioning waste are already being safely managed across the estate and more is set to arise as facilities are decommissioned. The radioactive isotope strontium-90 is produced by nuclear fission. Significant amounts are found in radioactive wastes which therefore require appropriate management. Characterisation is an important step in understanding how best to manage these wastes, so the distribution and concentration of strontium-90 require accurate measurement.
Current analytical techniques rely on radiochemical methods which measure the energy released during radioactive decay. However, these procedures are labour-intensive and lengthy, requiring the strontium-90 to be chemically separated before it can be analysed. The potential for a more rapid alternative is being investigated, which enables the selective removal of interfering isotopes so that the strontium-90 can be measured accurately.
Using the latest-generation triple quadrupole inductively coupled plasma mass spectrometry
(ICP-QQQ-MS), the research focuses on assessing the effectiveness of the interference removal, and
determining the achievable limits of detection for a range of decommissioning waste samples. The
objective is to develop a methodology that could significantly reduce the time and labour required
for strontium-90 analysis, hence providing more information to plan decommissioning programmes.
Dr Ben Russell is part of the National Physical Laboratory team carrying out this NDA-funded research.
The former NDA-sponsored PhD student has been able to deploy and build on the skills developed through his PhD to address NDA decommissioning challenges. This highlights the benefits of longer-term investment in technical skills.
Instrument capabilities and sample preparation techniques investigated, active sample trials about to start.