Tracking Water Table Elevation with Seismic Refraction Method at CEER, Selinsgrove PA

Seismic refraction method was applied to track water table fluctuations and compared to ground water level from five monitoring wells at the Center for Environmental Education and Research (CEER) near Susquehanna University. The five monitoring wells recently drilled on CEER are part of a developing hydrological facility to be used for educational and research purposes. Two sets of seismic refraction explorations were implemented; one to evaluate water levels, and one to evaluate the geologic stratigraphy of the site. Ground penetrating radar was also implemented to assess the water table as an additional comparative method. Both seismic refraction and GPR results showed identical water level yet direct reading from the corresponding monitoring wells along the survey line were off. Water level monitoring in the observation well was acquired continuously with a pressure transducer as well manually during each seismic refraction reading. This gives an insight on the interaction between the groundwater and storm events and explains the nature of recharge of the aquifer. Data acquired through seismic refraction reveal a similar trend to that of data collected from the monitoring wells, however there is a difference in water level measured by each method. A detailed examination of well log Stratigraphy and the integration of all applied methods show that monitoring wells are being influenced by the lower region where the well screen is placed. This high hydraulic conductivity region allows more water flow than the upper region of the same layer causing a potentiometric surface within the wells to rise above the water table. This resulted in the construction of a calibration equation that allows the identification of the water table based on the water level in the well.