Stabilization of Lead-Contaminated Mine Soil Using Natural Waste Materials

Stabilization was applied as a remediation option for immobilizing lead (Pb) in contaminated mine soil. Four types of waste materials were used stabilizing agents, namely oyster shells (WOS), calcined (COS), natural starfish (NSF), and spent-coffee-grounds-derived biochar (SCGB). The Pb-contaminated soil treated with the agents ranging from 0 to 10 wt% curing period 28 days. toxicity characteristic leaching procedure (TCLP) employed evaluating effectiveness remedial process. Pb immobilization mechanism investigated using scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM-EDX) analyses. obtained results showed that TCLP levels decreased agent dosage increased. WOS COS immobilized effectively Application dosages 4 2 COS, respectively, sufficient compliance regulatory level 5 mg/L. For NSF SCGB treatments, wt%, necessary meet limit. found increase following order: < COS. chemical fraction analyses lower F2 (weak acid soluble) higher F3 (reducible) F4 (oxidizable) fractions most likely associated high immobilization. Moreover, SEM-EDX analysis effective could be strongly pozzolanic reaction products.