Remediation of a Chromium Contaminated Soil: Mechanical Response and Leaching Behavior

Chromium contamination of soils is a worldwide issue because of the risks related to such a heavy metal as it presents elevated carcinogenic, mutagenic, and teratogenic characteristics. This highlights the importance of developing feasible remediation strategies for chromium-contaminated sites. The present research employs the adjusted porosity/cement index ( η /( C iv ) 0.28 = 18, 20, and 23) to define the dosages for stabilizing a hexavalent chromium-contaminated silty soil, considering stabilization and solidification S/S approach. Mechanical (unconfined compressive strength, small strain stiffness, and durability) and environmental (solubility and leachability tests) were conducted on different compacted silty sand-Portland cement mixtures contaminated with hexavalent chromium considering a seven-day curing period. The main findings indicate the usefulness of the porosity/cement index approach in defining the dosage for S/S applications, particularly when considering the mechanical aspects. Also, the tested dosages were helpful in substantially reducing the solubility and leachability of chromium. Still, they were not capable of reducing to the toxicity and potability levels preconized by some agencies.