ASSESSMENT OF CONTAMINATION BY TRACE ELEMENTS WITHIN HOCKANUM RIVER WATERSHED AREA, CONNECTICUT

The Hockanum River originates from Lake Shenipsit in Rockville, CT and travels a total of 22.6 miles through the Papermill pond in Vernon, Union Pond in Manchester, and several other impoundments before emptying to the Connecticut River in East Hartford, CT. In 2022, the Department of Environmental Protection Agency (DEP) issued a fish consumption advisory due to high concentrations of per- and polyfluorinated alkyl substances (PFAS) in fish tissue samples from the river. While efforts have been made to look at PFAS and other pollutants, few information is available on the level of trace elements within the river. This study examined the overall impact of human activities on the concentrations and spatial distribution of major and trace elements along the Hockanum River, CT. A total of fifty-eight (58) stream sediment, along with their corresponding water samples were collected throughout the entire flow length of the river. During sampling, basic physicochemical parameters of the water column that include pH, temperature, total dissolved solids (TDS), and electrical conductivity (EC) were determined. In the laboratory, sediment samples were air dried, thoroughly homogenized, and sieved through a 2-mm sieve size, and analyzed for particle sizes, and organic matter fractions. In addition, samples were digested with aqua regia based on EPA 3052 method with CEM Mars 6 microwave and analyzed for seventeen (17) chemical elements using an ICP-OES at the CCSU Geochemical laboratory. Results of chemical elements in both water column and sediments exhibited spatial variability which mostly correlated with OM fractions and fine grain particles in sediments. Using GIS map overlay, correlations between the concentrations of chemical elements and human activities within the drainage systems were examined. Results provide timely data on the stream sediments enrichments, and overall impact of human activities along the Hockanum River.