A Study on the Measurement of Activity Concentrations of Pu and Am and Their Isotopic Ratios in the Radioactively Contaminated Soil

방사능으로 오염된 토양에 대한 Pu 및 Am 방사능 농도 및 동위원소비 측정에 대한 연구

  • Lee, Myung Ho (Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute) ;
  • Song, Byoung Chul (Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute) ;
  • Park, Young Jai (Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute) ;
  • Kim, Won Ho (Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute)
  • 이명호 (한국 원자력 연구소 원자력 화학연구부) ;
  • 송병철 (한국 원자력 연구소 원자력 화학연구부) ;
  • 박영재 (한국 원자력 연구소 원자력 화학연구부) ;
  • 김원호 (한국 원자력 연구소 원자력 화학연구부)
  • Received : 2004.10.21
  • Accepted : 2004.11.16
  • Published : 2004.12.25

Abstract

Soil samples collected from around the BOMARC Missile Site were measured for their activity concentrations and isotopic ratios of Pu and Am isotopes with particle sizes. The activity concentrations of Pu and Am in the BOMARC soil were remarkably higher than the fallout levels, and the activities decreased nearly exponentially with an increasing particle size of the soil due to a decreasing surface area. The activity ratios of Pu-238 / Pu-239, 240, Pu-241 / Pu-239, 240 and Am-241 / Pu-239, 240 observed in the BOMARC soil were much lower than those attributed to the nuclear reprocess plants and the Chernobyl fallout. Also, the atomic ratio of Pu-240 / Pu-239 in the BOMARC soil was remarkably lower than the fallout value influenced by the nuclear weapons testing and the Chernobyl accident. The atomic ratio of Pu-240 / Pu-239 was so close to the value of the weapons grade Pu released from the crash of a B52 plane in the Thule of the Greenland, such that the Pu isotopes detected in the BOMARC soil could have originated from the weapons grade plutonium.

Keywords

Pu and Am isotopes;Soil sample;Activity concentration ratio;Atomic ratio

Acknowledgement

Supported by : 과학기술부

References

  1. M. H. Dai, K. O. Buesseler, J. M. Kelley, J. E. Andrews, S. Pike, J. F. Wacker, J. Environ. Radioactivity, 53, 9-25(2001).
  2. S. E. Rademacher, E. V. Sheely, D. D. Thomas : Lakehurst Naval Air Engineering Station (NAES) radiological baseline survey in support of USAF BOMARC missile accident site remediation waste transportation plan, New Jersey, IERA-SD-SR -2002-0004, 2002.
  3. M. H. Lee, C. W. Lee, Nucl. Instr. Meth. A, 447, 573-576(2000).
  4. Y. Muramatsu, W. Ruhm, S. Yoshida, K. Tagami, S. Uchida, E. Wirth, Environ. Sci. Technol., 34, 2913-2917(2000).
  5. Y. F. Yu, H. E. Bjornstad, B. Salbu, Analyst, 117, 439-442(1992).
  6. J. H. Harley, J. Radiat. Res., 21, 84-104(1980).
  7. Ionizing Radiation: Sources and Biological Effects, United Nations Scientific Committee on the Effect of Atomic Radiation, 1982, Report to the General Assembly, United Nations, New York, 1982.
  8. E. Holm, A. Aarkrog, S. Ballestra, H. Dahlgaard, Earth Planet. Sci. Lett., 79, 27-32(1986).
  9. Ken O. Buesseler, J. Environ. Radioactivity, 36 69-83(1997).
  10. M. H. Lee, C. W. Lee, Radiochimica Acta, 84, 177-181(1999).