Submarine Groundwater Discharge to Long Bay, SC: Preliminary Assessment of Land Use Impact, Geological Controls, and Nutrient Loads

A combination of geophysical and geochemical techniques will characterize geologic controls on submarine groundwater discharge and quantify discharge rates and nutrient fluxes to Long Bay, SC.  The geophysical approach will integrate continuous electrical resistivity profiles with previously collected Chirp subbottom profiles to reveal submarine groundwater seep locations and the associated geological structures.  Radon-222 activities will provide volumetric discharge estimates.  Nutrient concentrations will be measured across the beachface and in bottom waters nearshore.  The product of discharge estimates and nutrient concentrations will yield nutrient flux estimates.  All data will be integrated in a GIS/3-D visualization environment.  Digital land use layers will be combined with all other data to assess any spatial relationships between discharge hotspots, nutrient flux variability, land use characteristics.