SEDIMENT FINGERPRINTING IN THE LAKE MACATAWA WATERSHED

Lake Macatawa has been classified by the State of Michigan as a hypereutrophic lake due to its high levels of phosphorus. These high levels are attributed to nonpoint source sediment pollution in the surrounding watershed. In this study, suspended sediment samples in multiple streams and rivers in the watershed were collected and analyzed. Various analytical techniques were employed in an effort to fingerprint the sediment in the hope of identifying the sources of the sediment pollution in the watershed. Scanning Electron Microscopy-Electron Dispersive Spectroscopy (SEM-EDS), Proton Induced X-Ray Emission (PIXE) spectrometry and Auto Analyzer III Continuous Flow Analysis (AAIII) for phosphate were used on samples of the suspended sediment in an effort to indentify the trace elements as well as the inorganic phosphorus concentrations bound to elements in the sediment. Just as sand mineralogy can be used to identify sources of dune sands, the elemental composition of these sediments can help determine where the source of the sediment lies within the watershed.