North-Central Section - 49th Annual Meeting (19-20 May 2015)

Paper No. 10
Presentation Time: 1:30 PM-5:30 PM

GRAIN MINERALOGY, PROVENANCE, AND ENVIRONMENTAL ISSUES OF LAKE MICHIGAN SANDS


TRAUSCH, Brian N., Geology Dept., Augustana College, 639 38th St, Rock Island, IL 61201, briantrausch11@augustana.edu

The littoral drift system of Lake Michigan controls the way in which sediments are transferred and deposited in different locations around the lake bed. A suite of base metals such as lead, chromium, antimony, among others are likely to be found in Lake Michigan sands as a result of the steel industry in NW Indiana. Nine samples were collected from beaches along the southern shore of Lake Michigan between Waukegan Harbor (approximately 80 miles northwest of the steel industry on the Indiana lakefront) and Warren Dunes State Park (approximately 40 miles northeast of the industrial area) June through August of 2014. A tenth sample was taken in Lake Bluff from an accumulation of dark material on the shore during December of 2014. These samples were analyzed with X-Ray Fluorescence spectroscopy to determine major and trace element compositions. Data is anticipated at later date, and the compositions are being assessed. I expect to find traces of slag and heavy metals originating from the Indiana Harbor steel industry area. The varying concentrations of heavy metals should reflect the littoral drift system of the lake and anthropogenic shore alterations. My results will be compared to previous site assessments and recognized environmental condition parameters to determine whether hazardous conditions exist at my sampling sites. Initial analysis of the data show elevated levels of chromium at 540 ppm in the sample taken from accumulated darker material in Lake Bluff (dermal sensitization likely to occur at levels over 350 ppm). Only three of the samples displayed levels of lead above 27 ppm, all of which were located at the Lake Bluff sampling site (Uncontaminated soils are defined as being below 50 ppm). The data from significant metals will be presented using a map with spatial analysis in relation to the steel industries on the Indiana lakeshore.