The current conceptual model, which will be refined in collaboration with the Management Transition Advisory Group or MTAG, is to install a series of paired mainland/barrier island transects of up to 10 monitoring stations each, consisting of 4-individual wells within 3 boreholes at each station.
Borehole #1 contains two wells nested in the same borehole. Both of these wells measure water electrical conductivity, water depth and temperature (CDT) continuously. One of these is 10 feet deep and the other is 100 feet deep. The 100-foot deep well doubles as an Electromagnetic Induction (EMI) tool access port designed the same way as the EMI access ports used in the United States Geological Survey’s (USGS’s) saltwater intrusion monitoring program.
Type #2 wells measure electrochemical conditions and electrical resistivity to study corrosion rate and soil resistivity that are affected by saltwater intrusion.
Type #3 wells are multilevel water sampling wells with 7 isolated zones up to 100 ft. depth; these wells will allow collection of water samples to test for many potential analytes (EC, T, DO, Ca2+, Na+, K+, HCO3- Cl-, SO42-TKN, NO3-/ NO2-, Mn, Fe, S2-, CH4, DOM).
A weather station will be paired with devices to monitor subsurface water, salinity, and corrosion conditions at different depths. Collected data will be available on a public dashboard.
Figures below show example potential paired transect configurations and an example barrier island transect cross-section, respectively.
