Abstract
Monitoring deformations in mining pillars in salt mines is crucial for detecting spalling, cracks, and distortions caused by internal pressures, with the aim of preventing mining accidents and maintaining structural integrity. At Salina Ocna Dej, annual measurements have not utilized drone technology, which was recently introduced in Romania. The measurements conducted with the DJI Phantom 4 Pro Plus drone in 2020 and 2024 provided essential data on changes in the mining pillar. In 2020, difficulties caused by air currents slightly affected the measurements, but by 2024, improved conditions allowed for more accurate results. The horizontal sections taken at various elevations revealed significant spalling and distortions, particularly on the eastern and western sides, with substantial rupture in the northwest corner and displacements on the northern side. Comparing the data from the two measurement sets showed a significant difference in precision, highlighting the need for regular inspections to prevent premature erosion and avoid accidents.