An Assessment of the Environmental Impact of Coal Mining Through Acid Mine Drainage and Soil Degradation From Makum Coalfields, Upper Assam, India: A Case Study

Abstract

Acid mine drainage and soil erosion are significant problems in the coal mining area. It affects the water quality and soil quality, henceforth affecting plant growth and most aquatic life. During the last two decades, coal mining areas were increased by 194 hectares in Makum coalfield (Assam), which led to an increase in acid mine drainage and soil loss. In this paper, the water chemistry of water samples was analyzed, and annual soil loss near the area of Makum coalfield was calculated to investigate the most affected region by Acid Mine Drainage (AMD) and soil erosion. The Watershed delineation, slope angle, elevation contour map, and drainage system of 57 km2 of the study area were developed by ArcGIS Pro. The Universal Soil Loss Equation was used to estimate the amount of annual soil loss. The USLE parameter was assessed using a Digital Elevation Model with a 30-meter X 30-meter resolution. The result indicates that the quality of drainage near the mines was highly acidic. Also, compared to the area near the riverside, the proximity of mines is more affected by soil erosion and needs improvement.