SUMMARY
Pumpung Village is located along the Cempaka tributary, which is where diamond mining activities take place. It serves as a disposal site for the waste generated from diamond mining activities. Mercury (Hg) is still used as a mass weighting material in the washing process to separate gold contained in the ore. The objective of this research is to analyze the quality status and characteristics of river water for pH, dissolved oxygen (DO), chemical oxygen demand (COD), and mercury (Hg) parameters. It also aims to analyze the chemical quality characteristics of soil for pH and mercury (Hg) parameters at the diamond mining site in Pumpung Village, Cempaka District, Banjarbaru City. The identification of water and soil characteristics is conducted in situ and through laboratory tests. The test results are tabulated and analyzed descriptively using the water quality standard of PP No. 22 of 2021 and the South Kalimantan Governor Regulation No. 5 of 2007. The water quality status analysis uses the STORET method, while the soil quality analysis uses a descriptive comparison of the results from both sampling locations. The results of the river water testing during morning and afternoon sampling show average pH values of 6.5550 and 6.907, and DO values of 4.167 mg/L and 5.867 mg/L, respectively, indicating that they still meet the standard water quality requirements. However, the average COD values of 31.767 mg/L and 37.567 mg/L, as well as Hg values of 0.017 mg/L and 0.022 mg/L, indicate that they do not meet the standard water quality requirements. As for the soil testing, the average pH values fall within the acidic range, specifically 4.8 and 4.9, and mercury (Hg) is detected at each sampling point, with average values of 0.0665 mg/kg and 0.8980 mg/kg. The Hg values tend to be higher at the second location (L2). This indicates that diamond mining activities contribute to the pollution of water and soil at the Pumpung Village mining site. The water quality analysis using the STORET method yields a value of -24, falling within the range of -11 to -30, classifying the river in Pumpung Village as Class C, indicating a moderate level of pollution.