Monitoring Hazardous Wastes Using Space-Borne and Ground-Based Spectroradiometry — Sokolov Lignite Mines, Czech Republic

Authors: Chevrel, S; Kopačková, V; Bourguignon, A; Rojík, P; Metelka, V Paper is not available for download Contact Us

DOI https://doi.org/10.36487/ACG_repo/852_60

Cite As:
Chevrel, S, Kopačková, V, Bourguignon, A, Rojík, P & Metelka, V 2008, 'Monitoring Hazardous Wastes Using Space-Borne and Ground-Based Spectroradiometry — Sokolov Lignite Mines, Czech Republic', in AB Fourie, M Tibbett, I Weiersbye & P Dye (eds), Mine Closure 2008: Proceedings of the Third International Seminar on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 651-662, https://doi.org/10.36487/ACG_repo/852_60



Abstract:
This paper presents a preliminary study which aims at identifying the locations of the most significant sources of acid-mine drainage at the Sokolov lignite open pit, using space-borne and ground-based spectroradiometry. Mining in the Sokolov basin began in 1793. From 1890, large-scale mining operations eventually led to considerable environmental damage in the region, such as surface and subsurface water contamination, landscape and land use changes, erosion of dump slopes, stress on vegetation, soil contamination, etc. The lignite is still under exploitation at several places, while the former-exploited areas are undergoing various rehabilitation procedures, including overburden backfilling of the open pits, re-vegetation of dumps and the construction of recreational areas such as golf courses. Sokolovská uhelná closure planning includes an artificial lake, filling the former Medard open pit and extending over 500 hectares with a 50 m depth, for recreational purposes. Rehabilitation needs acid mine drainage (AMD) sources and dissemination to be taken into consideration. Mineral spectroscopy, from airborne or space-borne sensors, as well as ground measurements, represents an alternative to conventional geological methods of analysis and an efficient way to characterize mining areas and assess the potential for AMD. Multispectral advanced space-borne thermal emission and reflection radiometer (ASTER) satellite data, together with ground-based spectroscopy (ASD Fieldspec 3® spectroradiometer), were applied in order to assess their capabilities in identifying locations of the most significant sources of AMD discharge at the Sokolov open-pit mine site. Once resampled to ASTER-spectral bands, spectroscopy measurements have rendered the following findings:  Iron oxy-hydroxides have prior diagnostic absorption, in the visible and the near-infrared (NIR) – in this particular case at the wavelength of 0.8070 μm (ASTER band 3). This absorption feature was found to be more visible on the hematite group minerals and the goethite minerals showed a more distinctive reflection feature at 0.661 µm (ASTER band 2).  The Jarosite mineral group, Na-jarosite and ammonio-jaraosite, have similar spectral properties in the visible-NIR region to the iron oxy-hydroxides, but shows a supplementary absorption feature at 2.167 μm (ASTER band 5).  Clays are the most common minerals at the open pit mine site and can thus be found in different geological materials as a part of intimate mixtures. They have the most distinctive absorption feature – near 2.209 μm (ASTER band 6). The first results comparing mineral maps, derived from ASTER imagery with field investigations, correlated with XRD analyses, demonstrating the ability of spectral remote sensing in mapping mineral species such as secondary iron minerals. Image processing identified jarosite as a part of the mixture material, in accordance with conducted XRD analyses. Monitoring Hazardous Wastes Using Space-Borne and Ground-Based Spectroradiometry — S. Chevrel et al. Sokolov Lignite Mines, Czech Republic

References: