STUDY OF GEOCHEMICAL CHARACTERIZATION AND MINERALOGY ANALYSIS IN INTERBURDEN A2-B LAYER COAL MINE PT BUKIT ASAM (PERSERO) TBK.

• Main Author: Arsita Dewi, Nita
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/81777
• Institution: Institut Teknologi Bandung

One of the mining activities is the process of overburden stripping. This activity will expose the minerals that exist in the rocks. When exposed, the material containing sulphide minerals will go through an oxidation process. Presence of water in contact with the oxidation products can lead to acid mine drainage (AMD). Acid mine drainage have a high level of acidity with low pH and high dissolved metal content (TDS). In proceeding a Good Mining Practice system, PT Bukit Asam (Persero) Tbk. need to manage the mine in order to minimize the formation of AMD, especially in Muara Tiga Besar Mine (MTB). In predicting the formation of acid mine drainage, there are several methods that can be done both in the field and in the laboratory. The method is a geochemical characterization of the static test and kinetic test. Geochemical parameters on the static test are total sulfur, acid neutralizing capacity (ANC), paste pH, and net acid generation (NAG). The kinetic test using free draining column leach test. The results showed that eight samples from interburden A2-B Muara Tiga Besar classified as PAF (potential acid forming) material and the other two are categorized as NAF (non-acid forming) material. The samples are located just above and below the coal seam tend to classified as PAF with high total sulphur value. PAF rock spreading pattern in interburden layer A2-B across the region of IUP PT Bukit Asam shows the tendency of acidity level is spatially higher from east to west. This conclusion is based on the static test and water quality test, state that the MTB Mine which is the westernmost region of IUP has PAF rock with the lowest NAG pH and paste pH and value highest metal content.