Accurate measurement of 55Fe in radioactive waste

Intercomparison exercise on difficult to measure radionuclides in activated concrete—statistical analysis and comparison with activation calculations

“…The radiochemical methods utilised in the DTM analysis of the activated concrete have been summarised by Leskinen et al [4]. The utilised procedures were mainly based on published references [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27], but also internal procedures and modifications based on discussions between the participating laboratories. The main focus was given for 3 H, 14 C, 55 Fe and 63 Ni whereas 36 Cl and 41 Ca were optional.…”

“…In general, the applied methods were divided between the volatile (e.g. 3 H, 14 C and 36 Cl) and non-volatile (e.g. 41 Ca, 55 Fe and 63 Ni) DTMs.…”

“…In thermal oxidation systems, volatile DTMs were trapped in different trapping solutions e.g. 3 H in 0.1 M HNO 3 solution, 14 C in CarboSorb or CarbonTrap solutions, and 36 Cl in 6 mM Na 2 CO 3 solution. The 3 H and 14 C solutions were directly analysed in the trapping solutions using Liquid Scintillation Counting (LSC) whereas 36 Cl solutions required further purifications using AgCl precipitation and anion exchange resin prior to the LSC measurements.…”

“…The 3 H and 14 C solutions were directly analysed in the trapping solutions using Liquid Scintillation Counting (LSC) whereas 36 Cl solutions required further purifications using AgCl precipitation and anion exchange resin prior to the LSC measurements. One laboratory also carried out the 14 C and 36 Cl analysis using a closed system on a heating mantle.…”

“…Similar to the first year, eight laboratories participated; three from Finland, one from Sweden, two from Norway, one from Denmark, and one from France. The focus was on determination of 3 H, 14 C, 55 Fe and 63 Ni whereas 36 Cl and 41 Ca were optional. In addition to DTMs, the key gamma emitters present in the activated concrete, namely 152 Eu and 60 Co, were measured.…”