Particulate plutonium released from the Fukushima Daiichi meltdowns
Journal
Science of The Total Environment
Journal Volume
743
Start Page
140539
ISSN
0048-9697
Date Issued
2020-11
Author(s)
Kurihara, Eitaro
Takehara, Masato
Suetake, Mizuki
Ikehara, Ryohei
Komiya, Tatsuki
Morooka, Kazuya
Takami, Ryu
Yamasaki, Shinya
Ohnuki, Toshihiko
Horie, Kenji
Takehara, Mami
Law, Gareth T.W.
Bower, William
W. Mosselmans, J. Frederick
Warnicke, Peter
Grambow, Bernd
Ewing, Rodney C.
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.
Publisher
Elsevier BV
Type
journal article