title: Distribution of 137Cs in soil along Ta-han River Valley in Tau-Yuan County in Taiwan.
abstract: Environmental 137Cs contamination was suspected from accidents at spent fuel storage pits of a research reactor site in the Ta-han River valley in Taiwan. In order to further characterize this contamination, soil samples were collected and measured by a gamma-spectroscopy system in 1999. It was found that 137Cs contamination is distributed up to 4 km from the reactor in an area covered mostly by rice and plant fields. 137Cs concentration in the topsoil ranged up to about 1000 Bq kg-1, as compared with soil beyond the contaminated area, which does not exceed 15 Bq kg-1. Spatial distribution of 137Cs was characterized by strong non-uniformity, which complicated our understanding of the distribution pathway of the radionuclides. The highest concentrations of 137Cs, up to more than 1000 Bq kg-1, were found within a few rice fields. The relative location of these rice fields and the water supplies from local streams suggested that the 137Cs was distributed along water pathways in the valley.
authors.affiliation: Institute of Environmental Health Sciences, School of Medicine, National Yang Ming University, 155 Li-non st, Section 2, Shih-Pai, Taipei 11200, Taiwan.
authors.forename: Y B
authors.initials: YB
authors.lastname: Nabyvanets
authors.forename: T F
authors.initials: TF
authors.lastname: Gesell
authors.forename: M H
authors.initials: MH
authors.lastname: Jen
authors.forename: W P
authors.initials: WP
authors.lastname: Chang
mesh_terms: D000383:Agriculture; D002588:Cesium Radioisotopes / Q000032:analysis*; D004784:Environmental Monitoring; D018788:Radioactive Hazard Release; D012990:Soil Pollutants, Radioactive / Q000032:analysis*; D013624:Taiwan
chemical_list: D002588:Cesium Radioisotopes; D012990:Soil Pollutants, Radioactive