Tailings in this study are the result of Jigs washing in the mining process. This 'mining waste' interesting to study because there is no information that explains the relationship between mineral content and geochemistry so that it has not been widely used. The method used to determine the mineral and geochemical characteristics of tailings is X-ray spectroscopy using XRD and XRF. The mineral found in the tin mine tailings on northern Bangka Island (Pemali, Jebus, Tempilang, and Mapur) is quartz and kaolinite. The trace element shows main Rare Earth Elements (REE) Ce, La, Nd, Sm, Ta, and Y with various concentrations. Radioactive elements are found: Uranium and Yttrium. They are thought to originate from type I granite rocks with acid-to-moderate magma-forming compositions. The affinity of magma forming granite tailings studied was High K Calc Alkaline and Calc-Alkaline. This explains the presence of REE and the radioactive elements in tailings even though they are not present in carrier minerals such as monazite and xenotime.

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PT Allied Inco Coal Jaya (PT. AICJ) is a company that work in coal mining industry. This research is done at underground mining located at main shaft tunnel at +347 metres above mean sea level (MASL) with 334,04 m in length with room and pillar method as its mining method. This research is using quantitative method. From the calculation obtained, the total of incoming water into the mining production area is 6.13 m3/hour. For the actual incoming from well is as much as 13.32 m3/hour with the total head is as big as 29.56 m, as the time needed to discharge is 6.45 hour. Making the dewatering layout design for the incoming water at elevation of +347.32 MASL to main sump at +318 MASL with total length of 201.6 m, while the water discharged at continuous pumping at elevation +306 MASL moving toward +347.43 MASL with total distance 341.32 m. with the addition to incoming water there is an increase in the pumping working hours so it is concluded that there is difference between the planned cost and actual cost of Rp. 832,269.96.

This research was conducted to redesign the pumping system in the air drying process within a maximum of 25 days. The method used is descriptive and quantitative methods with actual data in the form of pressure and suction pipe elevation, pipe length and diameter, catchment area, actual discharge and pump head, location coordinates.The runoff discharge is 1.89 m3 / s, is prevented from entering the mine area by creating a channel with discharge flow of 2.12 m3 / s. The total volume on Shaft Lacat 4 is 34,591.7 m3 . The pump at a depth of 20 m has a discharge of 229.37 m 3 / hour, while a depth of 28 m has a discharge of 210.73 m3 / hour. Assuming the ground water is 200.64 m3 / hour, the addition of one pump with a discharge of 36 m3 / hour so that the drying time for 24 days is 11.8 hours. Production is stacking the sump of 1 x 1 x 1.5 m, making a channel with dimensions of 10 cm x 10 cm.

The Batu Ampar block is one of the ex-mining blocks in Bangka Regency where land revegetation has been carried out in 2019 and 2020. Observation of land realization is carried out by testing the accuracy of mapping using a base map from drone data and the success of the canopy cover level in accordance with the accuracy of the classification of the base map based on Regulations Head of the Geospatial Information Agency Number 15/2014. The results of processing and analysis show that the CE90 and LE90 accuracy test values for drone data geometry are 0.44 m and 0.86 m for the GCP georeference is said to be in class 3 on a scale of 1:2500 and class 1 on a scale of 1:5000. In the process without GCP georeference, the CE90 and LE90 values of 8.5 m and 6.8 m do not correspond to any class on the ideal scale for the layout of the Batu Ampar reclamation block mapping.