Well Installation and Soil Data Collection
Monitoring well sites were chosen based on specific environmental conditions which have a major influence on the status of the groundwater . For Kiawah Island , this considered variables such as surface elevation , soil type , and island region . The installation of groundwater monitoring was conducted using boring equipment made by Eijkelkamp ( Netherlands ) developed for agricultural research . It consists of a hand augering kit that is used to dig through the vadose zone above the saturated soils where groundwater exists .
After boring 12-17 feet below the soil surface using the Eijkelkamp boring set , a well apparatus was inserted to the 4-inch casing at the excavation site . This well apparatus consists of a 10-foot section of well screen pipe attached to a 10-foot section of solid PVC pipe . The well screen allows groundwater to naturally flow into the well and fully submerged below the soil surface at each well site . The remaining PVC pipe section extends the well to the surface for accessing groundwater and fixing monitoring equipment . While removing the casing , pool screen sand was placed around the well apparatus . After removing the casing , the remainder of the boring hole was sealed with bentonite clay from a depth of 2-3 feet to prevent surface water contamination . Native soil was then placed on top of the bentonite seal . In total , fully installing a well typically took around 4 hours with a crew of 2-4 people . A map showing the general distribution of groundwater monitoring wells is shown in Figure 5 .
Groundwater Monitoring
To allow for data collection from installed wells , a period of one week was given to allow conditions within the well to stabilize or settle . The wells were subsequently bailed with a metal rod to flush water from the site and introduce native groundwater from the surrounding saturated soils . Following the initial assessment of well conditions , each of the wells were deployed with a datalogger which captures depth and temperature ( Solinst 3001 LT ), with a select few wells deployed with equipment to capture water conductivity for studying salinity ( Solinst 3001 LTC ).
Sites capturing conductivity levels were chosen based on higher than normal conductivity levels taken from point measurement readings . Probes were programmed to continue collecting data at 30-minute intervals in the first year to capture minute changes in groundwater conditions and facilitate groundwater mapping efforts . Data gathered from the wells is compensated using a barologger centrally deployed at the Kiawah Conservancy office ( 80 Kestrel Court , Kiawah Island , South Carolina ) and compared with data from the Kiawah River Bridge Tide Station and Weather Station located at the Timbers Hotel . Analysis of groundwater conditions and the creation of water budgets was also conducted by replicating the methodology used by Kassabian , Callahan , and Upchurch for a small watershed area within the ACE Basin NERRS ( 2015 ). This analysis was conducted with coding developed by the Kiawah Conservancy within the R Statistical Package ( R Core Team , 2022 ) in R Studio IDE ( RStudio Team , 2022 ).
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NATURE-BASED SOLUTIONS MANUAL FOR KIAWAH ISLAND