Geotechnical Factors Affecting High- and Low-wall Stability in Opencast Coal Mines

Conventional cost accounting at the mines studied could not report on physical structure or materials flow, so environmental costs such as water, energy and consumables stayed hidden and chances to cut them were lost. Four case studies across different commodities and mining methods showed the same limitations. An environmental management accounting model is proposed to identify and allocate those costs.

Electrical and electromagnetic ground surveys were run over a Waterberg profile with borehole logs and three dimensional seismic data as control, to test whether cheaper methods can match seismic reflection for locating coal and faults. Resistivity tomography at two electrode spacings, frequency and time domain electromagnetics, controlled source audio magnetotellurics and magnetics were all acquired. Results are preliminary.