ANTHROPOGENIC IMPACT OF AN HISTORIC HAT FACTORY ON MERCURY AND TRACE ELEMENTS CONCENTRATIONS OF SURROUNDING TOPSOIL, DANBURY CT

The city of Danbury, nicknamed the “hat capital of the world,” is located in eastern Connecticut and was once the center of the hat-making industry in America. The industry was prevalent here for more than 150 years, from the 1780s to the 1940s. At its prime, there were several hat factories in Danbury which produced 5 million hats a year. The production of hats requires the use of chemicals such as nitric acid and mercury nitrate solutions to help turn furs into felt. Due to little regulation, the waste byproducts from those factories were improperly disposed of into the surrounding environments. This study examined the impact of one legacy hat factory on the concentrations, mobility, and spatial distribution of mercury and eleven chemical elements (Fe, As, Ni, S, P, Zn, Mn, Cu, Al, Cd, Cr, Hg), with the overall goal of examining their fate and transport within the critical zone environment. To address this objective, a total of sixteen topsoil samples were collected around the factory, and analyzed for acid and soluble extractable elements, basic soil parameters such as particle size distribution, and organic matter contents. In addition, stream sediment and water samples from a nearby Still River were collected and analyzed. Using JMP statistical software, all the geochemical data were evaluated. Calculation of the soil Enrichment Factors (EF), Geoaccumulation Indices (GI), and multivariate statistical analysis were used to examine the degree of soil enrichments as well as the overall fate and transport of mercury within the topsoil of a historic hat factory.