Mobile conveyor modules are used for transporting aggregate over a long distance, or for transferring the aggregate to other modules, and for stacking the aggregate either linearly or radially. These modules may be used in various combinations by themselves or in combination with existing conveyor systems and bridge stackers to stack aggregate on and off multi-lift leach pads and on multi-lift dump sites. The mobile conveyor modules are designed to be steerable and self-propelled, providing increased maneuverability and reducing relocation/reformation time. Multiple stacking methods may be used with the mobile conveyor modules either separately, or at the same time, advance and retreat stacking, the stacking of a berm, or the filling in of a corridor, may be accomplished on a variety of terrain.