MEASUREMENT OF ACTINIDES IN ENVIRONMENTAL-SAMPLES BY PHOTON ELECTRON REJECTING ALPHA-LIQUID SCINTILLATION

This work describes the adaptation of extractive scintillation with a Photon-Electron Rejecting Alpha Liquid Scintillation (PERALS) ((TM) OR DELA, Inc.) spectrometer to the analysis of actinides in environmental samples from the Savannah River Site (SRS). Environmental quality ass urance !standards and actual water samples were treated by one of two methods; either a two step direct extraction or, for more complex samp les, pretreatment by an extraction chromatographic separation prior to measurement of the alpha activity by PERALS. Accuracy of the method o f +/- 5% was confirmed on a number of sample types at activity levels of a few pCi/l or less: Minimum detectable activities were estimated f or counting times up to a week in duration and were as low as 0.003-0. 005 pCi/l.