Abstract
Results of a technical/economic feasibility analysis of conceptual "retreat" surface area mining systems are presented. The study determined the engineering feasibility, probable costs, and practicality of conceptual "retreat" area mining systems and compared the conceptual systems with commonly practiced area surface mining techniques. Designs for two retreat mining systems were developed which utilize haulage schemes laid out so far as to reduce or eliminate the number and maintenance of haul ramps through spoil areas. The study determined that, in simple models, the economics of retreat mining are fundamentally unfavorable. However, there are some mining or environmental circumstances under which full retreat or semiretreat mining systems become advantageous.
