CHLORIDE CONCENTRATIONS IN DOMESTIC WELLS AND PROXIMITY TO ROADWAYS IN VERMONT, 2011-2018

The Vermont Department of Health and U.S. Geological Survey analyzed the concentrations of chloride in groundwater sampled from 4,319 domestic wells across Vermont between 2011 and 2018. Ninety of these wells were sampled twice and 4,229 were sampled once. This presentation is an assessment of the spatial trends determined from the Health Department Laboratory dataset of chloride concentrations and geographic well information. Statistical analysis of this dataset revealed distinct patterns in the distribution of chloride in domestic wells across the state. Wells closer (< 100 m) to a paved road had significantly higher concentrations of chloride than wells further (> 100 m) away. Also, wells in urban areas and in high population density areas also had significantly higher concentrations of chloride. These findings may have implications for deicing salt application across all levels of management, from state to local. Further investigation of chlorides impact on water corrosivity and lead-leaching potential from household plumbing is necessary.