[3M09-15] Environmental Dynamics

[3M13] Tritium activity concentration and behavior at coastal region of Fukushima

*Michio AOYAMA^1,2, Sabine Charmasson³, Yasunori Hamajima⁴, Celine Duffa³, Daisuke Tsumune⁵, Yutaka Tateda⁵ (1. Univ. of Tsukuba, 2. Fukushima Univ., 3. Institute de Radioprotection et de Sûreté nucléaire (IRSN), 4. Kanazawa Univ., 5. Central Research Institute of Electric Power Industry)

Keywords:tritium, Fukushima Dai-ichi Nuclear Power Plant, seawater, fish, river

In 2014, the tritium activity concentration along the Fukushima coast except near the Fukushima Dai-ichi Nuclear Power Plant (FNPP1) ranged from 90 Bq m-3 to 175 Bq m-3, and it was lower rather than the tritium activity concentration before the FNPP1 accident. The tritium radioactivity concentration was highest near the FNPP1 site and similar on both the north and south sides of FNPP1 while the 137Cs activity concentration was low at the north of FNPP1 and high at the south of FNPP1. This suggests that the source of tritium is the Fukushima Daiichi nuclear power plant and rivers locates both the north and south side of FNPP1.