Measured Ni-63 contents in Savannah River Site high level waste and Defense Waste Processing Facility glass product by Ni-selective ion exchange purification and beta-decay counting

We describe tests of EiChrom Industries' Ni-selective ion exchange resin fo r use in analysis of Ni-63 in Savannah River Site high level waste. We repo rt measurement of 63Ni content in two sets of Savannah River Site glass pro duct from the Defense Waste Processing Facility. The Ni-63 beta-decay activ ity was chemically separated in quintuplicate from fission product and plut onium alpha-beta activities of up to 10(3) times the observed 63Ni content. The separation used a Ni-dimethlyglyoxime precipitation followed by radioc hemical purification using the Ni-selective extraction chromatography resin . Further removal of interfering activity was based on diagnosis of observe d radioactivity in each successive product phase. We analyzed eleven plant glass product samples using seven spiked standard addition duplicates to me asure Ni-63 recovery in the separations. Selected liquid scintillation beta -decay spectra are shown to validate the method. Interpretation of accuracy is based upon three distinct comparisions to predicted Ni-63 content.