ABSTRACT
Development of resources often leads to environmental problems especially in open pit coal production since surface layer is removed with the vegetation at the first stage of the development. AMD is one of the serious environmental problems caused by mining activity. When a surface layer is removed in mining activity, sulfide minerals are exposed to oxygen and water, and the minerals react with them. Hydrogen ion which is produced by the chemical reaction leads to a decrease of pH, and the acidic condition has a negative impact on the surrounding environment (Jennings et al. 2008). Harmful heavy metals such as chromium or lead, moreover, dissolve in water with a decrease
1 INTRODUCTION
1.1 Coal production in Indonesia
Coal is an essential resource for our daily life. The demand for coal has been increasing every year with development in the technology in the world. Indonesia is one of the major coal-exporter and coal-producing countries; therefore, the coal production is planned to be increased in the future with the increase of the demand for coal all over the world.
