Mineralogical control of the size distribution of stable Cs and radiocesium in riverbed sediments

Linking heterogeneous distribution of radiocaesium in soils and pond sediments in the Fukushima Daiichi exclusion zone to mobility and potential bioavailability

“…Also, small fractions (<11%) were leached during the first sequential extraction steps (using 1 M ammonium acetate), suggesting a low ion exchange of NH 4 þ with sorbed Cs. This is in good agreement with the 10-17% 137 Cs associated to the exchangeable fraction in Fukushima soils and sediments reported by other authors and the hypothesis that radiocaesium is largely irreversibly sorbed (Kaneko et al, 2015;Saito et al, 2014;Tanaka et al, 2018). These authors also reported a significant fraction of 137 Cs in the corresponding geochemical phases (>75% in sediments, >63% in soils), which is in good agreement with our sequential extractions, where ~80% 137 Cs for sediments and 89-99% 137 Cs for soils was associated with the strongly oxidizable and extraction residue fractions.…”

“…Retention of radiocaesium contamination will also be affected by characteristics of the soil and sediment. Tanaka et al (2018) demonstrated that 137 Cs presented an equally strong retention in all the different fractions of Fukushima riverbed sediments. Samples analysed in this work were characterised by very low activity associated to clay (Fig.…”

Towards the application of electrokinetic remediation for nuclear site decommissioning

“…The surge in interest of radiocaesium remediation is particularly concentrated in Japan and South Korea, with a significant number of publications coming from these countries in recent years. We note also that 137 Cs is frequently examined in combination with 60 Co, an activation product of the neutron flux of stainless steel materials (e.g. pipework).…”

Radiocesium interaction with clay minerals: Theory and simulation advances Post–Fukushima

“…One of the most important observations regarding radiocesium adsorption in Fukushima soils is that weathered biotite is a primary adsorbent Mukai et al, 2014Mukai et al, , 2016aMukai et al, , 2016bKikuchi et al, 2015). For example, recent experiments showed that illite and weathered biotite are the primary radiocesium-bearing phases in silt-and sand-size fractions of Fukushima soil (Tanaka et al, 2018). Note that biotite in this article is defined as a Fe-rich phlogopite and/or a Mg-rich annite with the chemical formula K(Mg,Fe) 3 AlSi 3 O 10 (F,OH) as identified by X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS) and TEM (Kikuchi et al, 2015;Mukai et al, 2016a).…”