How opencast mining risks reawakening dormant geological faults

New study finds subsidence caused by groundwater extraction can take place as far as 20km from site of mine

The impact of opencast mining goes far beyond the edge of the pit. Studies of an opencast coalmine in western Germany show that opencast mining triggered extensive subsidence in the surrounding area and re-activated dormant geological faults.

Underground mines are often associated with ground subsidence, but less is known about the risks associated with opencast mines. Researchers from the GFZ Helmholtz Centre for Geosciences in Potsdam, Germany, studied satellite data and geological field measurements from the area around the opencast Rhenish coalfields, between Aachen and Cologne.