Coal is extracted by underground or by open cast method. The techno-economic feasibility of the deposit determines its mine-ability either through Opencast or Underground method. This was stated by Sh. Piyush Goyal, (Minister of state for Power, Coal & New and Renewable Energy (Independent Charge) in a written reply to a question in the Rajya Sabha. Coal reserves occurring at depth are better suited for mining by underground method. Coal in opencast mining is extracted either by dragline/shovel dumper combination or shovel dumper surface miner combination. In majority of the open cast mines higher capacity equipment of international standard is used. In underground method of mining, coal is extracted by continuous miner or by blasting and loading by Load haul Dumpers (LHD)/ Side Discharge Loaders (SDL). There is scope of improvement in mechanization in underground mining method of extraction in mines of Coal India Limited (CIL).
The Minister further stated that use of improved technology is an ongoing process. However, an Expression of Interest (EoI) was floated for inviting proposals from International Consultancy Firms / Organizations for Technology Development and Modernization of Mines of CIL. In response to this fourteen (14) International Consultancy Firms / Organizations having experience in consultancy services for coal mining activities have participated in the EoI. M/S KPMG Advisory Services Pvt. Limited was selected for undertaking the above stated study and has submitted a draft report, which is under examination of CIL, the Minister added.