3D resistivity and small-loop electromagnetic survey to identify leachate from livestock mortality burial

Abstract

Leachate from livestock mortality burial is very harmful for soil/groundwater environment so that adequate assessment approaches are necessary to manage burial site. Three-dimensional (3D) electrical resistivity imaging (ERI) method is relevant to many engineering aspects with environmental problems such as contaminant plumes as well as hydrogeological situations including aquifer characteristics, subsurface caves, and geothermal systems. A small-loop electromagnetic (EM) survey is also known to be an effective tool to delineate contamination areas and pathways of contaminant plumes from landfill. We describe the application of 3D ERI method and small-loop EM survey to identify the burial shape and the possible pathways of leachate from burial as a point source. To attain this end, we conducted 3D inversion of the 2D resistivity data sets acquired along several parallel and perpendicular lines and multi-frequency EM data for lattice nets over the livestock mortality burial. The 3D inversion result of resistivity data show well the subsurface structure of burial shape and pathways of leachate and inverted resistivity distributions with depth calculated from EM survey data also indicate the same trends as 3D ERI. However, resistivity resolution from EM survey is relatively poorer than that from 3D resistivity survey.