In this work, Î³-ray shielding and Cs immobilisation performances of high-density magnetite (MG) and iron powder (IP) in Portland cement (PC) based-S/S treatment were investigated. Experimental results were elaborated using a Î³-radiation shielding (Î³RS) index-based approach for assessing the effectiveness of in situ S/S of137Cs-contaminated soils. Main results reveal that the replacement of PC by MG or IP (up to 50%) leads to a marked increase (up to about 4-fold) in the Î³-ray shielding performance, whereas a further material addition decreases the S/S shielding performance. The highest Î³RS index of â¼26% (662Â keV) was found in the case of IP addition (33.3%). The use of MG-mixes allows reaching slightly slower Î³RS index jointly with the highest Cs-immobilisation of 97.8%. In this case, calculation shows a maximum137Cs-contamination level successfully treatable by in situ S/S up to â¼2.9 or â¼14.5Â kBq kgâ1for the realistic or low probability scenario, respectively, highlighting the possibility to remediate a very wide range of real contamination. Findings show MG - PC S/S as the best choice and could provide a basis for decision-making of S/S remediation of137Cs-contaminated sites.
|Titolo:||Stabilisation/solidification of Cs-137-contaminated soils using novel high-density grouts: gamma-ray shielding properties, contaminant immobilisation and a gamma RS index-based approach for in situ applicability|
FALCIGLIA, PIETRO PAOLO (Corresponding)
|Data di pubblicazione:||2017|
|Appare nelle tipologie:||1.1 Articolo in rivista|