A critical safety issue for open cast mines is slope stability and subsidence. Space geodetic techniques were used by researchers to monitor surface deformation over three open-pit mines in Germany. Significant land subsidence was observed over reclaimed areas ranging from 310 mm per year to over 500 mm per year. Mining areas reclaimed for agriculture also showed land subsidence. An advantage of the technique is that it can be used over large areas.
Long term monitoring of legacy mining sites would be valuable to warn surrounding communities and local government authorities of potentially unsafe conditions.