SURVEYING PERCHED WATER ON ANTHROPOGENIC SOILS USING NONINTRUSIVE IMAGERY
Robert S. Freeland, J.L. Branson, John T. Ammons, L. L. Leonard · Transactions of the ASAE · 2001
Wetland soils of anthropogenic origin are difficult to map using conventional soil surveying methods. Whiletraditional soil profile classifications are highly accurate at the borehole, beyond the sampling point the soilunit boundariesmust be visually extrapolated from the surrounding natural terrain. Anthropogenic soils are often erratic, many possessingunpredictable morphologies. Mapping precision is limited by additional sampling expense and site restrictions to excessiveborings. In order to increase mapping precision, this project compared measurements of shallow water table depth in copperminetailings as determined by (1) intensive conventional soil morphology classification, (2) groundpenetrating radar (GPR), and(3) electromagnetic induction (EMI). Groundpenetrating radar and EMI results were in agreement with water table depthsas determined by soil morphology. Wherever a wellformed densic contact was present, GPR and EMI interpretations of watertable depths when used alone were inconclusive. The combined technologies, employed in tandem, detected the densic contactlayer. Nonintrusive technologies improved mapping precision when combined and supplemented with conventional soilmapping techniques.