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This research was conducted in the North Sump area of the Air Laya Mining Unit at the Tanjung Enim, PT Bukit Asam Tbk. The sump is a former open pit mining area in the form of a very large basin. Previously this sump functioned to gathers water from the pit. Since there is no mining operation in that pit, then that sump-s functionality is changed into a disposal area, so the sump is needed to be dried. The draining plan is carried out with mine drainage and mine dewatering. Mine drainage is an effort to prevent runoff water to enters the sump. Mine dewatering is the effort to remove water from the sump by pumping. The initial draining plan is not able to dry the sump. It can be seen from the water surface-s elevation on the sump that has not decreased, so it is necessary to study the plan to drain the sump. The study conducted considers the calculation of the water balance. Water balance is influenced by inflow in the form of runoff water and outflow in the form of evaporation and pumping. Based on the calculation of the water balance, three alternatives are proposed in sump drying, which from each alternative can be seen changes in the volume and depth of the sump in a certain period. Alternative I is done by adding the number of pumps, the alternative II is done by increasing the pump impeller rotation, and the alternative III is done with alternative I and alternative II combination. The alternative chosen is alternative III with a drying time of 72 days.