The near-surface, active, electromagnetic (EM) method is based on the induction of electric currents in the ground by the magnetic component of electromagnetic waves generated artificially at the surface. An alternating current of variable frequency is passed through a coil of wire (a transmitter coil). This process generates an alternating primary magnetic field which, in turn, induces tiny eddy currents in the Earth, the magnitude of which is directly proportional to the ground conductivity in the vicinity of the coil. These eddy currents then generate a secondary magnetic field, which is intercepted by a receiver coil. The interaction between the primary and secondary magnetic flux and the receiver coil generates a voltage related to the subsurface’s electrical conductivity, expressed as milliSiemen/meter (mS/m). Near-surface EM methods measure subsurface electrical conductivity through the use of low-frequency electromagnetic induction. EM instruments for near-surface studies use a transmitter and receiver coil. Depth of exploration is a function of antenna frequency, separation, and orientation. Soil electrical conductivity, the inverse of electrical resistivity, is a function of subsurface materials’ electrical properties and pore fluids’ chemistry. Therefore, EM methods are instrumental in mapping changes in lithology. In shallow EM surveying, the ground’s electrical conductivity is measured as a function of depth and/or horizontal distance. Different rocks (and buried structures/objects) exhibit different values of electrical conductivity. Mapping differences in electrical conductivity aids in identifying anomalous areas worthy of further investigation.