Acid Mine Drainage Management at PT. Kaltim Prima Coal: A Summary of Improvement Studies

摘要

Improvement studies with particular reference to the rock weathering behavior have been conducting to evaluate current practices and find some alternative solutions for risks potency of AMD generation due to possibility of improper placement of materials at the final dumping area and shortfall of Non Acid Forming (NAF) material and top soil. The investigation at Sangatta North dumping areas showed that the finer size of particles influenced the surface layer to have potency as a barrier against the oxygen diffusion. In addition to that, separated investigation about lithology-based waste rock weathering behavior revealed that high rates of weathering for mudstone and siltstone were observed. Reactivity of sulphide mineral was also observed and took important roles in determining the water quality associated with AMD generation. Taking into account the geochemical and weathering behaviors, another study suggested that blending of NAF and PAF material might be tolerable and should be considered as an alternative solution to overcome NAF deficit.