Assessment of effectiveness in stabilization/solidification of arsenic-contaminated soil: long-term leaching test and geophysical measurement

Abstract

This study focused on evaluating the effectiveness of stabilizer/binding agents in immobilizing arsenic (As) in contaminated soil using both geochemical and geophysical monitoring methods. The effluent from the stabilizer/binding agent's application and control columns was analyzed, and the status of the columns was monitored using electrical resistivity (ER) and induced polarization (IP) methods. As stabilizers/binder, acid mine drainage sludge (AMDS) and steel slag (SS) were used, which delayed As and Ca leaching time and significantly reduced As leaching amount. Determination coefficients for As and Fe leaching exhibited elevated values (control column, R² = 0.955; AMDS column, R² = 0.908; and SS column, R² = 0.833). A discernible decline in the concentration of leached Fe was accompanied by a corresponding reduction in IP. The determination coefficients correlating IP and Fe leaching remained substantial (control column, R² = 0.768; AMDS column, R² = 0.807; and SS column, R² = 0.818). Such IP measurements manifest as instrumental tools in monitoring and assessing the retention capacity of applied stabilizer/binding agents in As-affected soils, thereby furnishing crucial data for the enduring surveillance of stabilization/solidification locales. This research posits a swift and continuous monitoring method for solidification/stabilization locales in situ.

Keywords: Arsenic; Contaminated soil; Electrical resistivity; Geophysical monitoring; Induced polarization; Long-term monitoring; Solidification; Stabilization.