GEOPHYSICAL INVESTIGATION AND INTERPRETATION OF THE MAGNETIC PROPERTIES AND SIGNATURE OF 55-GALLON COLD-ROLLED CARBON-STEEL HAZARDOUS-WASTE DRUMS

A new geophysical investigative technique using magnetic mapping was designed and utilized in several experiments to measure the three-dimensional vectoral magnetic field surrounding a single, unrusted, 55-gallon cold-rolled carbon-steel hazardous-waste drum. Several theoretical equations that describe possible physical models of magnetic induction in the drum were derived and compared to the measured field values. Through inverse modeling, a conceptual model of the magnetic field and the ferromagnetic properties of susceptibility and magnetic moment for the cold-rolled carbon-steel in 55-gallon drum geometry were determined. Rotation of the drums provided a measure of induced magnetization as well as the magnetic viscosity of the steel. The orientation of the drum was changed and the three-dimensional magnetic fields of different orientations were compared statistically for similarity. A typical geophysical site investigation for buried drums was simulated, and the ferromagnetic properties were substituted into search equations to locate the horizontal and vertical position of a buried drum.