BULK CHEMICAL INVESTIGATIONS OF PARKING LOT SEDIMENT FROM MIAMI UNIVERSITY HAMILTON REVEALS HETEROGENEITY AND CONCERN FOR STORMWATER MANAGEMENT

Parking lot sediment can be utilized for understanding the impacts of various sources of pollution because it records both vehicular components and direct atmospheric deposition. Parking lots can also serve as a pollutant source to aquatic systems as stormwater drains sediment and water. Parking lots at Miami University’s Hamilton campus in Hamilton, Ohio have stormwater drainage that directly connects to the Great Miami River which is a major drinking water source for the region. Samples were collected in four parking lots surrounding the Hamilton campus to evaluate the nature and extent of metal pollution and assess risk to aquatic systems. Previous scanning electron microscopy (SEM) work identified common minerals in the parking lot samples including plagioclase feldspar, iron oxides, quartz, and dolomite. Previous SEM work also identified zinc particulate and coal spherules in sediment in selected samples. Inductively coupled plasma - optical emission spectroscopy (ICP-OES) and inductively coupled plasma – mass spectrometry (ICP-MS) data were gathered for each of the 25 samples. Metals of environmental concern occurred at variable concentrations and include Ba (128-408 ppm), Pb (10-389 ppm), Zn (40-357 ppm), Cr (19-182 ppm), As (2.48-10.22 ppm), and Cd (0.0-0.19 ppm). Mo was elevated (~1 to 3 ppm) and single samples had high Sn (492 ppm), and Sb (17 ppm). Modest correlations occur between elements suggesting mixing of pollutants from different sources and with background materials. Variation in results also suggests heterogeneity in pollution but may also be a function of sampling density as suggested by single sample highs. Installation of sediment traps are warranted for the parking lots. This work serves as an important comparative data set for ongoing studies of metal pollution throughout Butler County and for postindustrial cities in the Midwest.