ENVIRONMENTAL GEOCHEMISTRY OF SEDIMENTS AND SOILS IN ROCK ISLAND COUNTY: HEAVY METALS IN THE DIRT

This study investigates soil samples from three sites in Rock Island County, Illinois for anthropogenic heavy metals: Pb, Zn, Cr, As, Cd, Ni, and Cu. Samples were collected fro contrasting sites: Hodge Park ravine (urban Rock Island, IL), an older residential site (urban Moline, IL), and Augustana’s Collinson Ecological Preserve (rural Milan, IL). The Collinson Ecological Preserve serves as a control site, as there is no evidence of anthropological disturbances, although we cannot rule out the introduction of airborne metals. The Hodge Park ravine is hypothesized to be contaminated by heavy metals that have been washed in from nearby streets and urban sources. The residential site is also hypothesized to be contaminated, particularly by Pb since the wood frame house was constructed in 1900. The latter two sites have soil samples collected from two depths, 20 and 50 centimeters. Soil samples were milled and are currently being analyzed using a Rigaku Supermini X-Ray Fluorescence Spectrometer (XRF). The results from this analysis will help understand the extent of anthropogenic heavy metal contamination in Rock Island County, processes by which metals are introduced to the system, and processes by which metals move through the system.