SOURCES, DISTRIBUTION, AND TRANSPORT OF MERCURY AND OTHER TRACE ELEMENTS WITHIN FARMINGTON RIVER SEDIMENTS, HARTFORD COUNTY, CT

The Farmington River located within the Hartford County, Connecticut starts in Becket Massachusetts, and flows for 47 miles before emptying to the Connecticut River. The river has a wide watershed that covers about 1580 km², and flows through many towns in Connecticut such as Canton, Farmington, Burlington, Avon, East Granby, Windsor, and Simsbury. Historical industrial sites such as coal power plants, abandoned landfills, and agricultural areas are common reported sources of anthropogenic contamination in Connecticut. This study examined possible sources, concentrations and spatial distribution of mercury, and fourteen (14) trace and major elements (As, Al, Cd, Cr, Cu, Fe, K, Ca, Mg, Mn, Ni Pb, S, and Zn) within stream sediments along the Farmington River, CT. To conduct the geochemical assessment, we collected a total of seventy-eight (78) stream sediment samples using shovel that was cleaned between sites. In addition, several fish samples were caught at various locations along the river. Sediment samples were air dried, thoroughly homogenized, and sieved through a 2-mm sieve size, and analyzed for particle size distribution using the hydrometer method. Subsets of the samples were analyzed for acid, and soluble extractable elements using ICP-OES, and basic soil parameters such as organic matter contents. Using Milestone DMA80 Mercury Analyzer, the total mercury concentrations in both fish and sediment samples were quantified. Results were plotted on the overlay of hydrology and land use land cover maps in order to show the distributions of analyzed chemical data. Calculations of Principal Component Analysis (PCA), Enrichment Factor (EF), and Geoaccumulation Indices (GI) on sediment geochemical data were used to determine the degree of sediment enrichment as well as contributions from both geogenic and anthropogenic sources.