28 FEBRUARY, 2025
Newsletter
Re-valorisation
In our last Newsletter we argued that closed mines represent a big and largely overlooked threat, which is essentially twofold: a) geotechnical stability of old tailings and waste dumps as well as the territories over the underground shafts and b) environmental contamination caused by residual acid and toxic materials or heavy-metal-laden wind-blown dust. While the responsibility for the control and monitoring of closed mines and their reclamation are usually defined nowadays, old mines are often “orphaned” and exist without any control or monitoring, which turns them into ticking bombs under the seats of local and state governments.
But closed mines also represent an opportunity, as the mine waste contains valuable materials, and their re-mining can bring significant environmental and social benefits.
Considering the deficiency of the extraction and processing methods of the past, when only a limited number of commodities were extracted, the waste rock can now be re-processed applying modern technologies with higher efficiency and thus with significant economic benefit as re-processing costs are lower than the initial mining costs.
This represents an attractive opportunity, explored by many private investors these days to extract many sought-after ores, including critical raw materials such as magnesium, cobalt, nickel, lead, copper, iron etc.
This renewed mining activities may also have additional positive social effects, as they may re-vitalise old mining regions, usually economically depressed. It can also bring back under environmental control old mining areas and ensure the adherence to the modern standards of control and consequent reclamation process.
But the problem any investor faces is the assessment of the reserves or valorisation of the materials.
And again, although field campaigns and laboratory tests dominate, some first level analysis can be obtained using only remote sensing techniques or a combination of the remote sensing and in situ techniques.
EO data and volumetric geophysical methods can support a waste valorisation concept by mapping the surface distribution of minerals and characterising subsurface waste characteristics (e.g., particle size, composition and variability) that are relevant for determining the feasibility for mine waste recovery.
GeoKinesia is a participant of a 12-party MOSMIN consortium, which includes research centres from Germany, Spain, and Romania, as well as private remote sensing specialists and world leading mining companies. The main objective is to develop holistic, full-site services for the geotechnical and environmental monitoring as well as valorisation of mining-related deposits based on a combination of earth observation (EO) and in situ geophysical data.
MOSMIN employs resolution-enhanced Copernicus spectral data, UAV-based topographic surveys, and cutting-edge, low-impact volumetric geophysical imaging methods such as ambient seismic and electrical resistivity tomography to derive integrated 3D models for the characterisation of secondary raw material resources in mine waste. These models will be supported and validated by mineralogical and geochemical studies. MOSMIN services will also enable tracking of stockpiles using time-resolved, multi-scale spectral data and periodic UAV photogrammetry and LiDAR surveys for volume and grade estimations.
MOSMIN is also actively promoting its services already at this early stage and is interested in establishing the relationship with the partners, who might be interested in re-valorisation service.
