Optimum mine dump design in Wardha Valley coalfields using finite difference numerical methods

Document Type : Research Article

Author

Dept. of Mining Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, India

10.22034/anm.2025.22754.1665

Abstract

The Wardha Valley coalfields are experiencing an acute shortage of dumping space for ongoing open-pit projects. This creates barriers to expanding the life of the projects and to developing the coal in greater depth. The acquisition of new land to dispose of waste material is challenging in the present socio-economic conditions of the region. The project administration cannot afford to lose large amounts of coal at greater depths. So, it is necessary to optimise the geometry of the waste dump slope. A steep slope can lead to a potential failure, and a flat slope may not be an economically viable option, so a balance must be found between these two aspects. In this study, a finite-difference numerical tool was used to account for the multiple factors contributing to the stability of mine dumps. The analysis was considered as a static and dynamic analysis using the FLAC2D finite-difference numerical modelling tool. The study proposed a viable alternative to waste dump geometry to optimise the use of natural resources in the Wardha Valley coalfields. The work showed that double-stage dumping is more advantageous. This study also showed that mining companies could accommodate 18% more waste rock in the available space without compromising safety by following this analysis.

Keywords

Main Subjects

References

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History

  • Receive Date: 04 February 2025
  • Revise Date: 11 June 2025
  • Accept Date: 06 September 2025

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