Investigations of road sediment in an industrial corridor near low-income housing in Hamilton, Ohio

The City of Hamilton, Ohio, is representative of numerous post-industrial midwestern cities that face a long-term environmental recovery from an extensive legacy of manufacturing. One area of concern is the extent and nature of metal pollution. This investigation is a survey of road sediment from an industrial corridor near low-income housing that is dominantly an African-American community. Linear correlations of geogenic elements are indicative of a single dominant geochemical source contributing to the region, and the compositions are consistent with previous background studies. Pb, Zn, and Cu are the major pollutants and samples exceed the mean concentrations compared to selected global sites by 66.7 % for Pb, 77.8 % for Zn, and 72.2 % for Cu. Correlations exist between several of the elements of concern, including zinc and copper, lead and chromium, zinc, and lead. In some cases, these correlations show multiple populations are present, suggesting that there are multiple sources of pollution with elemental signatures. Significant heterogeneity of metal pollution in the City of Hamilton exists, and complexities arise in a precise interpretation as heterogeneity may result from primary deposition of pollutants and secondary mobilization of pollutants or mixtures. Metals are mobilized, and Mn-oxides in the system appears to play a more important role than Fe-oxides in metal sequestration. GIS mapping of concentrations of some of the elements of concern shows spatial clustering dominantly near a metal recycling facility. This investigation compliments existing environmental studies of the region and demonstrates the need for more environmental forensic investigations.