Management of a contaminated mine soil: Effect of soil water content on antimony and arsenic immobilisation by iron‐based amendments and biochar composites

• DOI: 10.1111/sum.12968
• Publication Date: 2023-08-30T08:05:17Z
• Authors: Szimona Zarzsevszkij; Martina Vítková; Kristýna Zelená P...; Jan Kolařík; Barbora Böserle H...; Ľubomír Jurkovič
• Keywords: Metalloid; Soil conditioner

Abstract Alteration of wet and dry periods affects soil geochemical properties that drive contaminant availability mobility. Consequently, the efficiency remediation may vary, thus management needs to consider these variations. This study reveals effect moisture manipulation on behaviour toxic metalloids antimony (Sb) arsenic (As) immobilisation nanoscale zero‐valent iron (nZVI), biochar (BC) BC modified by or iron/ferrous sulphide (nZVI‐BC Fe/FeS‐BC). Soil samples from an abandoned Sb mining site were tested under laboratory conditions. Two distinct (organic mineral) layers incubated with each amendments (2% w/w application rate) at 50% 100% water holding capacity (WHC) soils for 10 weeks, subsequently extracted demineralised rainwater. The was significantly influenced different regimes type contaminant. Sorption onto secondary Fe minerals dominant Sb/As immobilizing mechanism. iron‐based showed up 97% 96% As. However, release generally higher WHC in rainwater extracts compared other conditions, indicating heavy rainfall flooding in‐situ increase In organic layer, enhanced formation leaching metalloid‐DOC complexes sorption competition negatively charged species DOC can be expected. Also, reductive dissolution As‐bearing metal oxides could lead observed flooded resulting exacerbated environmental health risks. Therefore, it is crucial (1) improve characteristics and/or develop effective soil; (2) test real field conditions evaluate long term wet/dry exposure; (3) proper risk assessment strategy area similar sites.