ANTIMONY REMEDIATION IN SHOOTING RANGE SOILS

Antimony (Sb) is a metalloid added as a hardening agent to the lead (Pb) core of bullets and widespread use of ammunition releases Sb into soil solution. There is a growing concern that Sb accumulation in shooting range systems may pose a serious contamination risk to groundwater, surface water, plants, and site reclamation efforts since Sb is both toxic and carcinogenic with toxicity and mobility dependent on speciation. Remediation of Sb in shooting range systems can be complicated due to the presence of co-contaminants like Pb, which has differing geochemical behavior than Sb and a divergent response to traditional remediation techniques, like phosphate and lime. The present study details a field and laboratory study investigating different iron (Fe) amendments to immobilize Sb via sorption and/or precipitation reactions. We also relate these controlled efforts to a similar site actively being used for training activities. We observed that an iron oxide-type amendment may be effective at reducing Sb mobility depending on the soil type. Overall, the results from this study highlight the importance of choosing an appropriate remediation strategy to target both Sb and Pb at shooting range sites.