Mine environment monitoring by interferometric synthetic aperture radar (InSAR) in northern latitudes – displacements due to geomorphologic changes in the open pit and the tailings ponds of Pyhäsalmi Mine, Finland

Monitoring the stability of mine structures, such as tailings ponds and open pits, is crucial for preventing environmental accidents and ensuring safety in general. Monitoring also continues after the active operation of a mine and possible mine area reuse activities have concluded. Currently, monitoring the structural stability of the mining area relies heavily on manual observations and measurements, for example, with highly accurate global navigation satellite system (GNSS) real-time kinematic positioning (RTK) applications in established control points. Consequently, monitoring large areas requires laborious measuring. Applying measuring based on remote sensing (RS) decreases the amount of fieldwork required and, in addition to large coverage and frequent repetition in measuring, it may also support monitoring the control points safely in possibly unstable areas. Satellite-based interferometric synthetic aperture radar (InSAR) is an alternative for measuring terrain displacements in large mining areas. Some limitations remain, as terrain coverage and weather conditions can hinder InSAR analysis, especially in northern latitudes. In this study, InSAR was used to measure terrain displacement due to geomorphologic changes at the Pyhäsalmi Mine, Finland, during the summer and autumn of 2022. Results provide insight into change patterns that can be detected and indicatively monitored by InSAR within mine environments in the northern latitudes.