EVALUATING THE CONCENTRATIONS OF ARSENIC AND OTHER TRACE ELEMENTS WITHIN AN AGRICULTURAL CATCHMENT OF THE TEN-MILE ESTUARY SYSTEM, LEBANON, CT

High arsenic concentration within the bedrock of New England area has been a major concern due to contamination of water supplies. Because arsenic is carcinogenic, WFSB news reported that Lebanon Elementary School shut down its drinking water supply on October 4^th, 2013 due to high concentration of arsenic. Possible sources of arsenic could be geogenic relating to the bedrocks geochemistry and anthropogenic from human activities. This project examined the impact of land use activities and geology on the chemical signature of arsenic and other trace elements in stream sediments within Ten- mile estuary system, Lebanon, Hartford County, CT with the view of evaluating mobilization and transport of solutes released from both bedrock and human activities. To address this, we sampled stream sediments from sixty five (65) different locations and analyzed them for particle size distributions, organic matter contents, and trace elements concentrations that include arsenic and twelve other elements (Al, Cd, Cr, Cu, Fe, K, Ca, Mg, Mn, Pb, S, and Zn). Results showed spatial variability in sediment concentrations which are related to the abundance of clay and silt fractions in our samples. Using statistical analysis, GIS maps with overlays of hydrology and land use activity, we relate concentrations of trace elements to land use. Calculation of element enrichment and geoaccumulation index on sediment samples show degree of enrichment and possible geogenic and anthropogenic sources of these elements.