GEOCHEMICAL ANALYSIS OF HEAVY METALS IN SEDIMENTS SURROUNDING THE BAUTSCH-GRAY MINE SUPERFUND SITE, JO DAVIESS COUNTY, ILLINOIS

Mining operations at the Bautsch-Gray lead mine site, located near Galena, IL, for the last eighty-six years have resulted in elevated levels of lead, zinc, and arsenic within the surface materials surrounding the mine property. Although remediation began in September of 2010 with the removal of 2600 m³ of contaminated soil from the mine site and neighboring residential properties, there has been continued migration of mine tailings. This has prompted a need to better understand the extent of contamination in the properties surrounding the mine tailings, at depth, and within particle sizes of mine tailings. A total of 29 surface soil samples, six depth samples, and two grain size analysis samples were taken from properties west, northeast, north, and south of the mine site. Samples were analyzed for heavy-metal contamination with an X-Ray Fluorescence spectrometer (XRF). Of the 29 surface samples, three samples exceeded Environmental Protection Agency (EPA) regulatory limits for heavy-metals in soils, and 24 samples exceeded background levels for heavy-metals. The highest concentrations of lead, zinc, and arsenic contamination were measured at 510ppm, 3024ppm, and 100ppm respectively. No migration of heavy-metals was seen to occur downward through the soil profile, suggesting that transportation of contaminants is occurring primarily due to runoff directly from the mine tailings. From this research it was determined that heavy-metals have continued to migrate into the properties west and north of the mine, with lead, zinc, and arsenic levels still exceeding EPA regulatory limits and background levels.