The decommissioning of nuclear facilities produces various types of radiologically contaminated waste. In addition, dismantlement activities, including cutting, packing, and clean-up at the facility site, result in secondary radioactive waste such as filters, resin, plastic, and clothing. Determining of the radionuclide content of this waste is an important step for the determination of a suitable management strategy including classification and disposal. In this work, we radiochemically characterized the radionuclide activities of filters used during the decommissioning of Korea Research Reactors (KRRs) 1 and 2. The results indicate that the filter samples contained mainly 3H (500–3,600 Bq·g−1), 14C (7.5–29 Bq·g−1), 55Fe (1.1– 7.1 Bq·g−1), 59Ni (0.60–1.0 Bq·g−1), 60Co (0.74–70 Bq·g−1), 63Ni (0.60–94 Bq·g−1), 90Sr (0.25–5.0 Bq·g−1), 137Cs (0.64–8.7 Bq·g−1), and 152Eu (0.19–2.9) Bq·g−1. In addition, the gross alpha radioactivity of the samples was measured to be between 0.32–1.1 Bq·g−1. The radionuclide concentrations were below the concentration limit stated in the low- and intermediatelevel waste acceptance criteria of the Nuclear Safety and Security Commission, and used for the disposal of the KRRs waste drums to a repository site.

1. Introduction
2. Experimental
    2.1 Equipment and Chemicals
    2.2 Filter Waste Samples and Acid Leaching
    2.3 Gamma Spectrometry
    2.4 Gross Alpha Measurement
    2.5 Determination of the Radioactivity of 55Fe,59,63Ni, 90Sr, 94Nb, and 99Tc
    2.6 Determination of the Radioactivity of3H and 14C
    2.7 Determination of the Radioactivity of 129I
    2.8 Calculation of the Minimum DetectableActivity (MDA)
3. Results and Discussion
    3.1 Acid Leaching of Filter Waste Samples
    3.2 Radioactivity Concentration Determinationof Gamma Emitters
    3.3 Radioactivity Concentration Determinationof Gross Alpha
    3.4 Radioactivity Concentration Determinationsof 55Fe, 59,63Ni, 90Sr, 94Nb, and 99Tc
    3.5 Radioactivity Concentration Determinationsof 3H and 14C
    3.6 Radioactivity Concentration Determinationof 129I
4. Conclusion
Acknowledgements
REFERENCES

• Kyungwon Suh(Korea Atomic Energy Research Institute) Corresponding Author
• Jung Bo Yoo(Korea Atomic Energy Research Institute)
• Kwang-Soon Choi(Korea Atomic Energy Research Institute)
• Gi Yong Kim(Korea Atomic Energy Research Institute)
• Simon Oh(Korea Atomic Energy Research Institute)
• Kanghyun Yoo(Korea Atomic Energy Research Institute)
• Kwang Eun Lee(Korea Atomic Energy Research Institute)
• Shinkyoung Lee(Korea Atomic Energy Research Institute)
• Young Sang Lee(Korea Atomic Energy Research Institute)
• Hyeju Lee(Korea Atomic Energy Research Institute)
• Junhyuck Kim(Korea Atomic Energy Research Institute)
• Kyunghun Jung(Korea Atomic Energy Research Institute)
• Sora Choi(Korea Atomic Energy Research Institute)
• Tae-Hong Park(Korea Atomic Energy Research Institute, University of Science and Technology) Corresponding Author