Rapid determination of super(90)Sr/ super(90)Y in water samples by liquid scintillation and Cherenkov counting

• Published in: Journal of radioanalytical and nuclear chemistry Vol. 300; no. 1; pp. 263 - 267
• Main Authors: Olfert, Jennifer M, Dai, Xiongxin, Kramer-Tremblay, Sheila
• Format: Journal Article
• Language: English
• Published: 01.04.2014
• Subjects: Blanks; Counting; Groundwater; Liquids; Nuclear chemistry; Radiochemical separation; Scintillation; Strontium
• ISSN: 0236-5731; 1588-2780
• DOI: 10.1007/s10967-013-2913-0

Strontium-90 ( super(90)Sr) is a ubiquitous contaminant at nuclear facilities, found at high concentrations in spent nuclear fuel and radioactive waste. Due to its long half-life and ability to be transported in groundwater, an accurate method for measuring super(90)Sr in water samples is critical to the monitoring program of any nuclear facility. To address this need, a rapid procedure for sequential separation of Sr/Y was developed and tested in groundwater samples collected from an area of riverbed affected by a super(90)Sr groundwater plume. Sixteen samples, plus spike and water blanks, were analyzed. Five different measurements were performed to determine the super(90)Sr and yttrium-90 ( super(90)Y) activities in the samples: direct triple-to-double-coincidence ratio (TDCR) Cherenkov counting of super(90)Y, liquid scintillation (LS) counting for super(90)Sr following radiochemical separation, LS counting for super(90)Y following radiochemical separation, Cherenkov counting for super(90)Y following radiochemical separation and LS counting of the Sr samples for super(90)Y in-growth. The counting was done using a low-level Hidex 300SL TDCR counter. Each measurement method was compared for accuracy, sensitivity and efficiency. The results following Cherenkov counting and radiochemical separation were in very good agreement with one another.