The effect of phosphate application on the mobility of antimony in firing range soils

• Published in: The Science of the total environment Vol. 409; no. 12; pp. 2397 - 2403
• Main Authors: Griggs, Christopher S., Martin, W. Andy, Larson, Steven L., O'Connnor, Greg, Fabian, Gene, Zynda, Greg, Mackie, David
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.05.2011; Elsevier
• Subjects: aluminum hydroxide; analysis; analytical methods; Antimony; Antimony - analysis; Antimony - chemistry; Applied sciences; buffers; Bullets; calcium phosphates; chemistry; compliance; Decontamination. Miscellaneous; Earth sciences; Earth, ocean, space; edaphic factors; Engineering and environment geology. Geothermics; Environmental Restoration and Remediation; Environmental Restoration and Remediation - methods; Exact sciences and technology; Firing; In situ stabilization; Inclusions; Kinetics; Leachate; leachates; leaching; lead; Lead (metal); methods; Phosphate; Phosphates; Phosphates - chemistry; Pollution; Pollution, environment geology; Projectiles; Rain; Rain - chemistry; Soil; Soil - chemistry; soil amendments; Soil and sediments pollution; Soil Pollutants; Soil Pollutants - analysis; Soil Pollutants - chemistry; soil types; Soils; solubility; sorption; Weapons; Weather; United States; North America; America; Antimony; In situ stabilization; Leachate; Phosphate; Phosphates; Pollutant behavior; Stabilization; Shooting; In situ; Pollution control; Immobilization; Mobility; Soil pollution; Trace element; Amendment; Phosphorus compound
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2011.02.043

Chemical and biogenic sources of phosphate are commonly accepted in situ treatment methods for immobilization of lead (Pb) in soil. The metalloid antimony (Sb), commonly associated with Pb in the environment, exists as either a neutral species or a negatively charged oxyanion. Antimony is used in the manufacture of bullets as a hardening agent, constituting approximately 3% of the bullet mass. Technological solutions to reduce the migration of metals from small arms firing range (SAFR) soils for environmental compliance purposes must be robust with respect to multi-component systems containing both cationic and anionic contaminants. The effect of varying physico-chemical soil properties on Sb mobility post-firing was assessed in this study for six soil types using common analytical protocols and methods related to regulatory criteria. The sands (SM and SP) demonstrated the greatest Sb solubility in post-firing leachate samples and therefore were selected to evaluate the effects of five commercially available stabilization amendments on Sb mobility. Enhanced Sb leaching was experimentally confirmed in the phosphate-treated soils compared to both the untreated control soil and the sulfur-based amendment, and thus suggests competition for negative sorption sites between Sb and phosphate. However, the 5% Buffer Block® calcium phosphate amendment did not exhibit the same enhanced Sb release. This can be attributed to the inclusion of aluminum hydroxide in the amendment composition. Technologies are needed that will adequately immobilize Pb without mobilizing oxyanions such as Sb. Further research will be required to elucidate binding mechanisms and redox conditions that govern the mobility of Sb on SAFRs. ► The effect of varying soil properties on Sb mobility assessed in six soil types.► Enhanced Sb leaching observed in phosphate treated soils. ► Possible competition for negative sorption sites between Sb and phosphate.► Technologies needed to immobilize Pb without mobilizing oxyanions such as Sb.