COAL MINING PRACTICES

India's total land area is 3.29 million sq. km and within this only 0.45% area (about 16,000 sq. km) is coal bearing. Out of this coal bearing area, active coal mining area is about 2500 sq. km. Maximum land degradation in coal mining is caused by open-cast mining and it is currently confined to 20% of the coal bearing land. Additional areas that could be used for open-cast mining would be around 5 to 10% of the coal bearing land. Thus, the area where land degradation has taken place and is likely to take place is around 0.2% of the land mass.

Underground production of coal peaked in the late seventies and has fallen slowly since then. Surface mining, on the other hand, has soared from16 to 160 million tonnes per annum. Of the 588 mines in India, 355 are under-ground, but opencast accounts for 75 percent of production and employs only 16 percent of the total mining work force. Productivity is higher in the opencast sector. However, the pace of growth cannot be sustained for long, as stripping ratios will increase and mining operations run into land access and other environmental problems. Underground mining is largely a 'board and pillar' operation. Longwall was introduced in 1978 and by 1993, 20 longwall units were installed.