GEOC 47 |
| Hurricane Katrina mobilized land-based contaminants as well as a significant quantity of bottom sediments. Consequently, previously reduced sediments were exposed to the oxygenated water column, abruptly altering the fate of redox active sediment-bound heavy metals. This study examines the effect of hurricane Katrina on the natural attenuation of heavy metals. Sediment cores and bottom water samples from the MS Sound have been collected seasonally starting from 12/6/05. Depth profiles were analyzed for Cr, Ni, Pb, As, and other metal concentrations. Metal-sediment phase associations were determined based on sequential extractions. Total “bioavailable” As concentrations in the sediment are below the probable effects level but did increase up to the 3/22/06 sampling date. Extraction data reveals that the increase in As is due to an increase in the amount of organic matter associated As; similar results were found for other metals. The metals are mainly associated with Mn/Fe-oxide and/or organic matter phases. |
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The Impact of Hurricane Katrina from an Environmental and Petrochemical Perspective
8:20 AM-11:40 AM, Monday, April 7, 2008 Morial Convention Center -- Rm. 213, Oral
Division of Geochemistry |