Stability of dragline waste rock dump in an Indian opencast coal mine

摘要

India ranks third in world coal production mainly due to 89% contribution from opencast miningrnor surface mining technology. Coal India (a major coal producing organization in India) produced 431.27rnmillion tonnes of coal in the year 2009-10 from opencast mining. It is pertinent here to mention that to minernout 431.27 million tonnes of coal from opencast mining, 695.29 million cubic metre of waste rock and soilrnwas excavated in the year 2009-10. But a major hindrance in sustaining this level of coal production fromrnopen cast coal mining is area of land involved. It is estimated that by 2025, total land to be involved due tornopencast coal mining will be 2925 sq. km (including 730 sq.km of forest land) as against the present coveragernof 1470 sq. km.rnThis socio-environmental predicament requires a solution and the only possible way to reduce the area of landrnaffected is to increase the slope angle of the waste dump embankments. However, this solution creates anotherrnproblem in itself i.e. the stability of the waste rock dump. It is considered as one of the major issues faced inrnthe open cast coal mining operation due to slope failures resulting in fatal accidents in some of the large opencastrnmines of India.