Trace Element Distribution at a Brownfield Site in Southern Illinois, USA

This study was conducted at a brownfield site in Carterville, Illinois, USA that was once an Illinois Ordnance Plant during World War II. The site was used for United States Army offices and ammunition manufacturing. After World War II, the site was turned over to Southern Illinois University to be used for vocational education and as a coal research facility. Over time, this location has experienced anthropogenic processes which have led to negative effects on the soil, including possible trace element contamination. According to US Soil Taxonomy, about 89% of the soils at the site are Epiaqualfs and Albaqualfs (Haplic Stagnosols and Planosols (Albic) in the World Reference Base (WRB)) while the other 11% are Hapludalfs and Fragiudalfs (Luvisols and Luvisols (Fragic) in WRB). This study was designed to examine the soils at the brownfield site for As, Cd, Cr, Cu, Hg, Ni, Pb, Sb, and Zn to determine whether they present human or environmental health concerns. Samples were collected with a hand probe from 130 locations at four depths (0-10, 10-20, 20-40, and 40-75 cm) in a grid. For part of the site, samples were collected at a density of 1.6 per ha, while the rest of the site was collected at 0.4 samples per ha. Air dried and ground (< 2 mm) samples were then scanned for 60 s each using an Evident Scientific Vanta Max portable X-ray fluorescence (PXRF) analyzer. Initial trace element pollution concerns were evaluated using the United States Environmental Protection Agency (EPA) Regional Screening Levels. Geographic information system interpolation maps were created to identify possible trace element hot spots. Using the screening levels, the majority of the trace elements analyzed are below the level of concern. However, As levels are higher than the EPA regulatory levels across the entire site. Cr levels exceed screening levels for Cr VI but are lower than allowed limits for Cr III. However, the PXRF does not allow for Cr speciation, so it is currently not known if Cr represents a concern. These results show that levels of As and Cr are a potential concern across the Carterville brownfield site due to anthropogenic pollution. Future research will investigate pollution indices to further codify potential negative human and environmental health impacts due to contamination at the site.