This study investigated the stabilization characteristics of Pb-contaminated soil at a clay pigeon shooting range through a pot experiment using clam shell treatment. Within 41 days of the treatment, the soil pH increased from 6.9 to 8.1 due to CaCO₃ in the clam shell. However, the feasibility of clam shell as a stabilization agent could not be directly confirmed, as Pb was not detected in most leachates, including the control, in both SPLP (synthetic precipitation leaching procedure) and TCLP (toxicity characteristic leaching procedure) tests. This indicates that limestone (CaCO₃), used as an ingredient in clay pigeon manufacture, had already stabilized the contaminated soil. In Pb fractionation, reducible Pb was the dominant form but significant changes in Pb speciation due to the treatment was not observed. Nevertheless, the total Pb concentration (sum of all fractions) in the treated soil was slightly lower than that in the control soil. This indicates that clam shell could be used as a stabilization agent due to its alkaline properties. The overall results suggest that reducing the loss of contaminated soil particulates should be prioritized over contaminants stabilization for sustainable management of clay pigeon shooting ranges.

Keywords: Stabilization, Shooting range, Clay pigeon, Clam shell, Lead