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Estimation of Uranium Particle Concentration in the Korean Peninsula Caused by North Korea's Uranium Enrichment Facility

북한 우라늄 농축시설로 인한 한반도에서의 공기중 우라늄 입자 농도 예측

  • Kwak, Sung-Woo (Korea Institute of Nuclear Nonproliferation And Control) ;
  • Kang, Han-Byeol (Korea Institute of Nuclear Nonproliferation And Control) ;
  • Shin, Jung-Ki (Korea Institute of Nuclear Nonproliferation And Control) ;
  • Lee, Junghyun (Korea Institute of Nuclear Nonproliferation And Control)
  • Received : 2014.06.13
  • Accepted : 2014.07.30
  • Published : 2014.09.30

Abstract

North Korea's uranium enrichment facility is a matter of international concern. It is of particular alarming to South Korea with regard to the security and safety of the country. This situation requires continuous monitoring of the DPRK and emergency preparedness on the part of the ROK. To assess the detectability of an undeclared uranium enrichment plant in North Korea, uranium concentrations in the air at both a short and a long distance from the enrichment facility were estimated. $UF_6$ source terms were determined by using existing information on North Korean facility and data from the operation experience of enrichment plants from other countries. Using the calculated source terms, two atmospheric dispersion models (Gaussian Plume Model and HYSPLIT models) and meteorological data were used to estimate the uranium particle concentrations from the Yongbyon enrichment facility. A maximum uranium concentration and its location are dependent upon the meteorological conditions and the height of the UF6 release point. This study showed that the maximum uranium concentration around the enrichment facility was about $1.0{\times}10^{-7}g{\cdot}m^{-3}$. The location of the maximum concentration was within about 0.4 km of the facility. It has been assumed that the uranium sample of about a few micrograms (${\mu}g$) could be obtained; and that few micrograms of uranium can be easily measured with current measurement instruments. On the contrary, a uranium concentration at a distance of more than 100 kilometers from the enrichment facility was estimated to be about $1.0{\times}10^{-13}{\sim}1.0{\times}10^{-15}g{\cdot}m^{-3}$, which is less than back-ground level. Therefore, based on the results of our paper, an air sample taken within the vicinity of the Yongbyon enrichment facility could be used to determine as to whether or not North Korea is carrying out an undeclared nuclear program. However, the air samples taken at a longer distance of a few hundred kilometers would prove difficult in detecting a clandestine nuclear activities.

북한 우라늄 농축 시설은 국내외적으로 심각한 위협중 하나이다. 특히 우리나라 입장에서는 국가 안보에 관련된 사안이므로 항상 주시하고 대비를 하여야 한다. 북한 미신고 우라늄 농축시설 탐지 가능성을 평가하기 위해 시설로 부터 장 단거리에 따른 공기중 우라늄 농도를 예측하였다. 북한 농축시설에 대해 국제 사회에 알려진 정보와 다른 국가의 농축 시설 운영 데이터를 근거로 북한 시설로부터 공기중으로 누출되는 $UF_6$ 선원항(source terms)을 계산하였다. 계산된 선원항과 영변 주변 기상 자료를 바탕으로 장 단거리 대기 확산 모델 - Gaussian Plume and HYSPLIT Models -을 이용하여 북한 농축시설 주변과 멀리 떨어진 남한 지역에서의 공기중 우라늄 농도를 결정하였다. 최대 공기중 우라늄 농도와 위치는 기상 조건과 방출 높이에 따라 시설 바로 근처와 0.4 km 이내 이고, 농도 약 $1.0{\times}10^{-7}g{\cdot}m^{-3}$로 나타났다. 본 논문의 가정을 적용하였을 때, 수 십 ${\mu}g$ 정도의 우라늄 샘플을 채취할 수 있을 것으로 나타났다. 이 수십 ${\mu}g$ 우라늄 양은 현대 측정 장비로 어려움 없이 측정 가능한 양이다. 반면에 영변 농축시설에부터 수 백 km이상 떨어진 남한 지역의 농도는 $1.0{\times}10^{-13}{\sim}1.0{\times}10^{-15}g{\cdot}m^{-3}$이하로 자연 방사성 우라늄 농도보다 낮은 값이다. 따라서 본 논문에 의하면 북한 영변 농축시설 주변에서 공기포집에 의한 신고 및 미신고 핵활동 탐지는 가능하지만 장거리에서는 불가능할 것으로 예측된다.

Acknowledgement

Supported by : 한국방사선안전재단

References

  1. Hecker SS. A return trip to North Korea's Yongbyon Nuclear Complex. CISAC. 2010.
  2. Kemp RS. Initial analysis of the detectability of $UO_2F_2$ aerosols produced by $UF_6$ released from uranium conversion plants. Science & Global Security. 2008;16:115-125. https://doi.org/10.1080/08929880802551172
  3. David A, Lauren B. Source terms for uranium enrichment plants. IAEA. 1997.
  4. Wogman N. History of STR 321-IAEA use of wide area environmental sampling in the detection of undeclared nuclear activities. STR-321. IAEA. 2010.
  5. UNSC. Report of the panel of experts established pursuant to resolution 1874. S/2014/147. UNSC. 2014.
  6. 이정현, 박일진, 안진수. 북한의 핵 프로그램 검증. KINAC/TR-008/2011. 한국원자력통제기술원. 2011.
  7. 이정현. 북핵 현안 분석. KINAC/TR-008/2012. 한국원자력통제기술원. 2012.
  8. Bosenberg J, Kalinowski MB. Detecting atmospheric $UF_6$ and HF as indicators for uranium enrichment. International Network of Engineers and Scientists Against Proliferations(INESAP).
  9. Kemp RS. Research note - source terms for routine $UF_6$ emission. Science & Global Security. 2010;18:119-125. https://doi.org/10.1080/08929882.2010.486719
  10. Homann SG, Fernando A. HotSpot Health Physics Codes Version 3.0 User's guide. LLNL-SM-636474. Lawrence Livermore National Laboratory. 2013.
  11. Roland D, Barbara S, Glenn R, et. al. HYSPLIT4 user's guide. NOAA. 2013.
  12. 이익환. 원자력연료 가공시설 가동중 환경감시 보고서. KAERI/CR-330/2008. 한전원자력연료(주). 2008.
  13. Riekkinen I, Jaakkola T, Pulli S, et. al. Analytical methods for wide area environmental sampling(WAES) for air filters. STUK-YTO-TR 184. STUK. 2001.