Characteristics of radio-cesium transport and discharge between different basins near to the Fukushima Dai-ichi Nuclear Power Plant after heavy rainfall events.
This paper describes watershed modeling of catchments surrounding the Fukushima Dai-ichi Nuclear Power Plant to understand radio-cesium redistribution by water flows and sediment transport. We extended our previously developed three-dimensional hydrogeological model of the catchments to calculate the migration of radio-cesium in both sediment-sorbed and dissolved forms. The simulations cover the entirety of 2013, including nine heavy rainfall events, as well as Typhoon Roke in September 2011. Typhoons Man-yi and Wipha were the strongest typhoons in 2013 and had the largest bearing on radio-cesium redistribution. The simulated137Cs discharge quantities over the nine events in 2013 are in good agreement with field monitoring observations. Deposition mainly occurs on flood plains and points where the river beds broaden in the lower basins, and within dam reservoirs along the rivers. Differences in137Cs discharge ratios between the five basins are explained by differences in the initial fallout distribution within the basins, the presence of dam reservoirs, and the input supply to watercourses. It is possible to use these simulation results to evaluate future radioactive material distributions in order to support remediation planning.
Sector of Fukushima Research and Development, Japan Atomic Energy Agency, 10-2 Fukasaku, Miharu-machi, Fukushima 963-7700, Japan. Electronic address: sakuma.kazuyuki@jaea.go.jp.
Kazuyuki
K
Sakuma
Sector of Fukushima Research and Development, Japan Atomic Energy Agency, 10-2 Fukasaku, Miharu-machi, Fukushima 963-7700, Japan; Center for Computational Science & e-Systems, Japan Atomic Energy Agency, University of Tokyo Kashiwanoha Campus Satellite, 178-4-4 Wakashiba, Kashiwa-shi, Chiba 277-0871, Japan.
Akihiro
A
Kitamura
Center for Computational Science & e-Systems, Japan Atomic Energy Agency, University of Tokyo Kashiwanoha Campus Satellite, 178-4-4 Wakashiba, Kashiwa-shi, Chiba 277-0871, Japan.
Alex
A
Malins
Sector of Fukushima Research and Development, Japan Atomic Energy Agency, 10-2 Fukasaku, Miharu-machi, Fukushima 963-7700, Japan; Center for Computational Science & e-Systems, Japan Atomic Energy Agency, University of Tokyo Kashiwanoha Campus Satellite, 178-4-4 Wakashiba, Kashiwa-shi, Chiba 277-0871, Japan.
Hiroshi
H
Kurikami
Center for Computational Science & e-Systems, Japan Atomic Energy Agency, University of Tokyo Kashiwanoha Campus Satellite, 178-4-4 Wakashiba, Kashiwa-shi, Chiba 277-0871, Japan.
Masahiko
M
Machida
Geosphere Environmental Technology Corporation, 2-1 Kanda-Awajicho, Chiyoda-ku, Tokyo 101-0063, Japan.
Koji
K
Mori
Geosphere Environmental Technology Corporation, 2-1 Kanda-Awajicho, Chiyoda-ku, Tokyo 101-0063, Japan.
Kazuhiro
K
Tada
Geosphere Environmental Technology Corporation, 2-1 Kanda-Awajicho, Chiyoda-ku, Tokyo 101-0063, Japan.
Takamaru
T
Kobayashi
Geosphere Environmental Technology Corporation, 2-1 Kanda-Awajicho, Chiyoda-ku, Tokyo 101-0063, Japan.
Yasuhiro
Y
Tawara
Geosphere Environmental Technology Corporation, 2-1 Kanda-Awajicho, Chiyoda-ku, Tokyo 101-0063, Japan.
Hiroyuki
H
Tosaka
D002588:Cesium Radioisotopes / Q000032:analysis*; D062406:Fukushima Nuclear Accident; D007564:Japan; D011834:Radiation Monitoring; D011891:Rain; D014872:Water Movements; D014875:Water Pollutants, Radioactive / Q000032:analysis*
D002588:Cesium Radioisotopes; D014875:Water Pollutants, Radioactive
Fukushima dai-ichi accident; Radioactive cesium; Sediment transport; Watershed model