Geochemical studies of potential acid-forming classification materials to reduce acid mine drainage formation

Abstract Acid mine drainage (AMD) is acidic wastewater produced in coal mining operations due to sulfide mineral oxidation. In compliance with the regulations of good mining practice procedures, each mining operation must conduct a geochemical study of the distribution of material classification categories to identify the potential acid-forming (PAF) or not acid-forming (NAF) materials to mitigate the AMD. This research conducted a field observation at one of the post-mining lakes of a coal mining operation in South Kalimantan. It determined materials or rocks that have the potential for acid formation using static tests with the Net Total Acid Producing Potential (NTAPP) method. The results of coring samples were processed to obtain rock lithology data for four drilling points, demonstrating one layer of low-capacity PAF material in borehole point A, one layer of low-capacity PAF material, and one layer of PAF material in borehole point B. Only one layer of PAF material was in borehole point C and borehole point D. These PAF/NAF data highlighted essential information about PAF/NAF, underscoring the significant role of our work in improving the strength and accuracy of mitigation plans and reducing acid mine drainage.