The document discusses different methods of surface coal mining including opencast mining. It describes the main pieces of heavy equipment used in surface coal mining operations, focusing on draglines. Draglines are large excavators suited for mining thick coal seams in areas with gentle slopes. The document provides details on different dragline working methods and specifications for draglines used at two example mining sites in India. Production statistics comparing digging and rehandling volumes for the two draglines over multiple years are also presented.