Stabilization/solidification of contaminated soils: a case study

Stabilization/solidification (S/S) is one of the most popular techniques for the remediation of heavy metal-contaminated soils. Compared with other mainstream remediation techniques, S/S could achieve remediation targets more rapidly at relatively lower costs. S/S involves the physical process of enclosing or binding heavy metal contaminants within stabilized soil matrix (solidification), and the chemical process of reactions between contaminants and S/S binders that reduce their mobility (stabilization). This chapter first reviews recent development in S/S treatment of heavy metal-contaminated soils, with an emphasis on new sustainable S/S materials. Meanwhile, research gaps and future directions are briefly discussed, with a focus on the multiscale characterization, long-term performance, multifunctionality, and field monitoring. Finally, two example cases studies by the authors’ research team are reported, with regard to the mechanical and hydraulic characteristics and acid rain resistance of ordinary Portland cement-stabilized Zn- and Pb-contaminated clayey soils.