Particulate plutonium released from the Fukushima Daiichi meltdowns

DOI: 10.1016/j.scitotenv.2020.140539

Authors: Eitaro Kurihara (Kyushu University) , Masato Takehara (Kyushu University) , Mizuki Suetake (Kyushu University) , Ryohei Ikehara (Kyushu University) , Tatsuki Komiya (Kyushu University) , Kazuya Morooka (Kyushu University) , Ryu Takami (Kyushu University) , Shinya Yamasaki (University of Tsukuba) , Toshihiko Ohnuki (Tokyo Institute of Technology) , Kenji Horie (National Institute of Polar Research; The Graduate University for Advanced Studies (SOKENDAI)) , Mami Takehara (National Institute of Polar Research) , Gareth T. W. Law (The University of Helsinki) , William Bower (The University of Helsinki) , J. Frederick W. Mosselmans (Diamond Light Source) , Peter Warnicke (Swiss Light Source) , Bernd Grambow (SUBATECH, IMT Atlantique, CNRS-IN2P3, The University of Nantes) , Rodney C. Ewing (Stanford University) , Satoshi Utsunomiya (Kyushu University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Science Of The Total Environment , VOL 743

State: Published (Approved)
Published: November 2020
Diamond Proposal Number(s): 21211

Abstract: Traces of Pu have been detected in material released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) in March of 2011; however, to date the physical and chemical form of the Pu have remained unknown. Here we report the discovery of particulate Pu associated with cesium-rich microparticles (CsMPs) that formed in and were released from the reactors during the FDNPP meltdowns. The Cs-pollucite-based CsMP contained discrete U(IV)O2 nanoparticles, <~10 nm, one of which is enriched in Pu adjacent to fragments of Zr-cladding. The isotope ratios, 235U/238U, 240Pu/239Pu, and 242Pu/239Pu, of the CsMPs were determined to be ~0.0193, ~0.347, and ~0.065, respectively, which are consistent with the calculated isotopic ratios of irradiated-fuel fragments. Thus, considering the regional distribution of CsMPs, the long-distance dispersion of Pu from FNDPP is attributed to the transport by CsMPs that have incorporated nanoscale fuel fragments prior to their dispersion up to 230 km away from the Fukushima Daiichi reactor site.

Journal Keywords: Uranium; Plutonium; Fuel fragment; Fukushima Daiichi; Cs-rich microparticle

Subject Areas: Chemistry, Environment


Instruments: B18-Core EXAFS , I18-Microfocus Spectroscopy

Other Facilities: Swiss Light Source

Added On: 15/07/2020 11:21

Discipline Tags:

Desertification & Pollution Earth Sciences & Environment Radioactive Materials Chemistry Materials Science Nuclear Waste

Technical Tags:

Imaging Spectroscopy X-ray Fluorescence (XRF) X-ray Absorption Spectroscopy (XAS) Extended X-ray Absorption Fine Structure (EXAFS) X-ray Absorption Near Edge Structure (XANES)