f MONITORING ENHANCED RECOVERY OF A MINE HEAP: AN APPLICATION OF REAL-TIME ELECTRICAL RESISTIVITY

Heap leaching is a large-scale processes of extracting metal from low-grade ore using basic principles of hydrometallurgy. The heap is constructed from stacking rubblized material on an impervious liner. Solution is applied at the surface to dissolve the metal, which is collected at the toe for further processing. The hydrodynamics of solution movement is highly dependent on internal heap structure, as well as mechanical changes that may occur over time. In some cases ore may remain unleached, especially if preferential flow channels are established or if chemical conditions have changed that make extraction untenable. To mitigate against these issues, a direct application of solution to troubled areas deep within the heap may provide a means to enhance recovery of otherwise lost metal. The application involves a pressurized delivery system, i.e., injecting solution through a perforated well.