Abstarct: In order to maximize recovery in underground uranium mines, to reduce the radiation absorption level of mine workers, to minimize environmental hazards, and to reduce of overall mining costs primitive safety and operational measures must be taken. One way to achieve this is to employ backfilling of excavated stopes with hydraulic concrete fillers in particular in the tunnel cut and fill method. Backfill is a material which is used to fill out the excavated cavities in underground environment to ensure the safety of mining operations. The hydraulic concrete filling method used in underground uranium mines not only enhances the in-situ ore recovery, but also leads to a reduction in the level of absorbed radiation ,from uranium ore, by mine workers. Series of experiments of radiation level were carried out on concrete hydraulic fillers, with varying mix design, to be used as backfill in underground environment. The test results show a significant reduction in absorbed radiation level as a function of backfill thickness and density. Moreover, it was shown in this study that in underground uranium mines, the excavated waste material and the polluted drained underground water can be used in the mix design of hydraulic concrete fillers and significantly reduce filling costs and environmental hazards. Additionally, the overall operating costs per cubic meter of backfill were determined for various mix designs and each mix design was evaluated in terms of geomechanical characteristics (28 day strength, stiffness, etc.) and mechanical parameters affecting backfill stability. Comparing the results, the most suitable mix design in terms of mechanical behaviour (strength, stiffness, etc.), absorption level of radiation, and overall operating costs were determined and recommended for use in underground uranium mines as backfill material.