title: Nuclear accident-derived (3)H in river water of Fukushima Prefecture during 2011-2014.
abstract: During 2011-2014, we measured (3)H concentrations in river water samples collected during base flow conditions and during several flood events from two small rivers in a mountainous area in Fukushima Prefecture, which received deposition of (137)Cs from the Fukushima Dai-ichi Nuclear Power Plant accident. (3)H concentrations above background levels were found in water samples collected during both base flow conditions and flood events in 2011. The (3)H concentrations during flood events were generally higher than those during base flow conditions. The (3)H concentrations in both rivers during base flow conditions and flood events decreased with time after the accident and reached almost background levels in 2013. We also measured (3)H concentrations in freshwater samples from 16 other rivers and one dam in eastern Fukushima Prefecture from 2012 to 2014 during base flow conditions. The measured (3)H concentrations were higher than the background level in 2012 and decreased with time. The (137)Cs inventory in the catchment area at each sampling point was estimated from air-borne monitoring results in the literature and compared with the (3)H concentrations. We found surprisingly good correlations between (137)Cs inventories in the catchment areas and (3)H concentrations in the water samples. Further studies will be necessary to clarify the reason for the good correlation.
authors.affiliation: Department of Radioecology, Institute for Environmental Sciences, 1-7 Rokkasho, Aomori 039-3212, Japan. Electronic address: sueda@ies.or.jp.
authors.forename: Shinji
authors.initials: S
authors.lastname: Ueda
authors.affiliation: Department of Radioecology, Institute for Environmental Sciences, 1-7 Rokkasho, Aomori 039-3212, Japan.
authors.forename: Hidenao
authors.initials: H
authors.lastname: Hasegawa
authors.affiliation: Department of Radioecology, Institute for Environmental Sciences, 1-7 Rokkasho, Aomori 039-3212, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Kakiuchi
authors.affiliation: Department of Radioecology, Institute for Environmental Sciences, 1-7 Rokkasho, Aomori 039-3212, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Ochiai
authors.affiliation: Department of Helical Plasma Research, National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292, Japan.
authors.forename: Naofumi
authors.initials: N
authors.lastname: Akata
authors.affiliation: Department of Radioecology, Institute for Environmental Sciences, 1-7 Rokkasho, Aomori 039-3212, Japan.
authors.forename: Shun'ichi
authors.initials: S
authors.lastname: Hisamatsu
mesh_terms: D002588:Cesium Radioisotopes / Q000032:analysis*; D062406:Fukushima Nuclear Accident; D007564:Japan; D011834:Radiation Monitoring; D045483:Rivers / Q000737:chemistry*; D012621:Seasons; D014316:Tritium / Q000032:analysis*; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D002588:Cesium Radioisotopes; D014875:Water Pollutants, Radioactive; D014316:Tritium
keywords: (3)H concentration; Base flow; Flood event; Fukushima Nuclear Power Plant accident; River water