HYDROLOGIC CHARACTERIZATION OF SINKHOLES IN AGRICULTURAL SETTINGS
The primary objective of this study is to characterize the hydrology and contamination potential of sinkholes in agricultural settings. The first task involves physical characterization of sinkholes at the Kentland Experimental Farm, Whitethorne, VA. The characterization is being conducted using a combination of Electrical Resistivity Tomography (ERT) and soil mapping. ERT, a geophysical tool, allows remote detection and modeling of subsurface features such as locations of pinnacles, mud-filled fractures, saturated zones, air-filled voids, solutional channels, and the bedrock-soil interface. Preliminary results show clear resolution of the bedrock-soil interface and reveal a bedrock surface that is an exaggerated approximation of surface topography with the addition of irregularities such as small sinks and pinnacles. The ERT and soil data will then allow accurate placement and installation of hydrological monitoring instrumentation designed to sample groundwater and agricultural contaminants as they move through a heterogeneous sinkhole environment.