This report presents the results of a three-phase investigation of the feasibility of using cemented coal waste in active underground coal mines to prevent mine subsidence. Coal waste was broadly defined to include waste from both coal preparation plants and coal- fired powerplants. Underground systems with potential for cemented backfill were determined through identification of current mining methods and available technologies for cemented backfilling and consideration of materials and systems constraints upon mining and backfilling integration. Technical concerns including operation, health and safety, materials utilization, environmental impact, applicability, and technical status were assessed for six systems that were identified as potentially feasible. Two of these systems were conceptualized in a hypothetical case history and developed to further assess their operational and economic feasibility. Comparisons of costs among both systems and with costs of surface disposal are presented. The conclusions concerning the present feasibility of using cemented backfill in active coal mines and potential avenues for further research are also presented.