Conservation of coal enjoins maximum recovery of in situ reserves of coal. The coal deposits in India occur mostly in thick seams and at shallow depths.
These aspects are taken into account during mine planning and operation in ensuring maximum recovery. Mechanised opencast mining in India is one of the important technologies of coal production of thick seam from shallow depth.
The percentage recovery by this method is up to 90 per cent of the in situ coal reserves. The coal production from opencast method in Indian mining is more than 80 per cent of total production.
This trend is likely to continue in the near future. The thick seam deposits earlier developed in Bord and Pillar (B&P) method or other methods of underground mining which had been standing on pillars for long in absence of a suitable technology of extraction have now in many cases become extractable by opencast mining.
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This method has been tried with success in some of the mines where underground mining was carried out in the past under the relatively shallow cover. The long wall methods are being applied in the case of underground mines to achieve higher underground production with higher percentage of recovery. The overall recovery in along wall technology is comparatively more than the recovery in Bord & Pillar mining.
The Coal Conservation and Development Act, 1974 provides for imposition of excise duty on coal despatches for meeting activities like conservation of coal, development/introduction of new technology in coal mines, safety in mines and assistance in mining operations. A number of research and development activities in the coal sector are carried out under the overall guidance and supervision of the Standing Scientific and Research Committee and its four sub-committees.