ABSTRACT
The article presents an assessment of post-mining hazards on a property located above shallow workings of a former hard coal mine, whose operations ceased in 1999 and has been undergoing flooding since 2000. The aim of the study was to determine the risk of discontinuous deformations (sinkholes) due to the geological structure of the overburden, changes in hydrogeological conditions, and the history of mining activities. The analysis considered geological and mining documentation, geodetic survey data from 2021–2023, and calculations based on the Chudek–Olaszowski and Kotyrba methods. It was found that the effects of continuous deformation subsided around 1994, and the minor surface subsidence observed in recent years (±15 mm) is related to rising groundwater levels and suffosion processes in the overburden. Classification results indicate a low risk for former longwall workings but a high risk for corridor (gallery) workings, categorizing the area as B23. Continuous monitoring, geophysical investigations, and exploratory boreholes are recommended, emphasizing the need for responsible land use in post-mining areas, even in the absence of current deformation symptoms.
