ARS | Publication request: The characterization of trace metals and organics in spent foundry sands over a one-year period

Submitted to: Journal of Residuals Science & Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 1, 2008
Publication Date: December 5, 2008
Citation: Dungan, R.S. 2008. The characterization of trace metals and organics in spent foundry sands over a one-year period. Journal of Residuals Science & Technology. 5(3):111-125.

Interpretive Summary: Each year foundries in the United States generate millions of tons of spent sand. The spent foundry sands (SFSs) are normally discarded, however, their beneficial use in manufactured soils and geotechnical applications will conserve natural aggregate supplies and landfill space. Before many states will consider allowing SFSs to be beneficially used in soil-related applications, a detailed characterization of trace metals and organics needs to be conducted. Excessive concentrations of trace metals or specific organics could be potentially harmful to humans and the environment. In this long-term study, we characterized trace metals and EPA-priority polycyclic aromatic hydrocarbons (PAHs) and phenolics in ferrous and non-ferrous SFSs over a one-year period. Overall, the total metal levels in the SFSs were not unlike those found in native soils, while the organic concentrations were relatively low. Metal leaching tests were also performed, which revealed that the SFSs have a low metal leaching potential under the specific test conditions. The data from this study suggests that the majority of SFSs are not hazardous in nature. This information will be useful to environmental regulators who are considering including SFSs in their beneficial use regulations.

Technical Abstract: Millions of tons of spent sand, used to create metalcasting molds, are generated by the foundry industry each year in the United States. Not surprisingly, spent foundry sands (SFSs) are an excellent substitute for virgin sands that are currently used in manufactured soils and geotechnical applications. The purpose of this study was to characterize trace metals and EPA-priority polycyclic aromatic hydrocarbons (PAHs) and phenolics in ferrous and non-ferrous SFSs over a one-year period. Overall, the total metal levels in the SFSs were like those found in native soils, while the PAHs and phenolic concentrations were relatively low. Metal leaching tests were also performed, which revealed that the SFSs have a low metal leaching potential under the specific test conditions. The data from this study suggests that the majority of SFSs are not hazardous in nature, except those that use olivine sands or are from brass foundries, due to the presence of elevated levels of Ni or Cu, Pb, and Zn, respectively. This information will be useful to environmental regulators who are considering including SFSs in their beneficial use regulations.