Ground Control -

: Optimizing the size of left-behind ore "pillars" to support the roof.

In photogrammetry and aerial mapping, are physical markers placed on the ground with known precise coordinates. Ground control points: why are they important? - Pix4D Ground Control

: Mine operators are often required to maintain a Ground Control Management Plan (GCMP) to document their approach to assessing and controlling geotechnical hazards. 2. Surveying & Drone Mapping : Optimizing the size of left-behind ore "pillars"