CHED 1107 |
| Lake Waban (Wellesley, Mass.) sediment appears to preserve a geochemical record of the Charles River watershed's complex history. Located downstream of a paint factory, the lake acted as an effluent depository for Cr and Pb from 1848 to 1928. We attempt to unravel the industrial history of Lake Waban through elemental and isotopic analyses of freeze cores from the deepest portion of the lake. Chemical analyses of sediments are conducted using X-ray fluorescence. Sediments are dated using gamma spectroscopy with 210Pb, 137Cs, 7Be, and 234Th radionuclide tracers and Pb sources are “fingerprinted” using 207Pb/206Pb and 206Pb/208Pb isotopic ratios. Preliminary analyses show elevated Pb levels in surface sediment and a maximum in Pb accumulation possibly during pigment production. Sediment sampling at the inlet and outlet examines present-day mobility and transport of Pb. Lake Waban's sediment profile reflects direct inputs from upstream activity, diffusion within sediments, and advection in the water column. |
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Undergraduate Research Poster Session: Environmental Chemistry
2:00 PM-4:00 PM, Monday, March 26, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Chemical Education |