GROUNDWATER QUALITY IN THE GORDON AQUIFER NEAR CHARLESTON, SOUTH CAROLINA
The current study focuses on the Gordon aquifer in the coastal counties near Charleston, South Carolina. Historical data described groundwater as a soft, alkaline, sodium bicarbonate type with areas of high fluoride concentrations and brackish water in areas near the coast. Wells open primarily to the Gordon aquifer were sampled during 2016 and 2018. A combination of domestic, public supply, and dedicated monitoring wells were purged and sampled, or vertically profiled for specific conductance to obtain water quality information. Water samples were collected and analyzed for field and laboratory water quality including the analysis of major cations and anions to determine the chemical composition. Results from the analyses were used to characterize the aquifer, locate the freshwater-saltwater interface, and compare to past studies in the same region. The results show similar trends in chemical quality, but a significant landward shift in the location of the freshwater-saltwater interface. These analyses can serve as baseline data and should be used as a comparison to identify future changes that may occur in water chemistry due to pumping.