Mapping and Quantifying Mine Waste Dump Expansion in the Katangan Copperbelt (Democratic Republic of the Congo): Implications for Ecological Remediation

The rapid expansion of mining activities in the Katangan Copperbelt has led to the accumulation of large volumes of mine waste dumps, which increasingly structure extractive landscapes. However, their spatial dynamics and morphological evolution remain insufficiently documented. This study analyses the spatio-temporal evolution of mine waste dumps in Lualaba Province (Democratic Republic of the Congo) between 2009 and 2025 in order to characterize their growth patterns, morphological changes, and spatial organization. Mine waste dumps were mapped through multi-temporal interpretation of high-resolution imagery in Google Earth Pro and analysed using GIS-based spatial metrics and statistical approaches. Results reveal a strong increase in dump area from approximately 1,900 ha in 2009 to more than 6,400 ha in 2025. The dynamics shift from a phase dominated by the proliferation of dumps between 2015 and 2020 to a phase characterized by the expansion and consolidation of existing deposits after 2020. Mutshatsha territory emerges as the main hotspot of mining intensification, while Lubudi territory displays more irregular dynamics and stronger morphological changes. Spatial metrics indicate a clustered distribution of dumps around active mining areas, followed by a partial spatial expansion toward new zones after 2020. Although most dumps occur relatively close to the road network, statistical analyses show that transport accessibility has only a limited influence on their size or emergence. Overall, these results highlight the importance of morpho-spatial monitoring of mine waste dumps for understanding mining landscape transformations and for supporting the spatial prioritization of ecological remediation strategies.