Analysis of 226Ra in the Groundwater Using the Gamma-ray Spectroscopy

감마선 분광법을 이용한 지하수 중의 226Ra 분석

  • Received : 2002.09.07
  • Accepted : 2002.12.09
  • Published : 2003.02.25

Abstract

The measurement of radium ($^{226}Ra$) in the groundwater was established using ${\gamma}$-ray spectroscopy without sample preparation. The background interference by air borne radon daughter nuclides was reduced by $N_2$ gas flow into the counting chamber. Leakage of radon gas produced in the radioactive equilibrium with radium and its daughter nuclides was prevented by use of the air-tighted aluminium container. We investigated the effect of air layer in the counting container. Radioactivity variation due to emanation of radon into the air layer was within the counting error range 5%. When the nitrogen gas was flowed around the detector, peak counts of ${\gamma}$-rays from the daughters of airborne radon was decreased and detection limit was decreased to 0.02 Bq/L. The detection limit of detector was lower than 0.74 Bq/L, the $^{226}Ra$ Maximum Contaminant Level (MCL) in the groundwater proposed by US Environmental Protection Agency (EPA). It was confirmed that $^{226}Ra$ radioactivity in the groundwater could be determined by the ${\gamma}$-ray spectroscopy.

Keywords

radium;HPGe detector;MCL;radioactive equilibrium;background reduction

References

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Acknowledgement

Supported by : 과학기술부