Spoil heaps

Bing Blackdamp Blower Bold Bord-nnd-pillar Sec spoil heap On-delicient air. typically rich in CO> (synonym stythe Signilicant point source of gas entering mine workings Mine roadway tor dead-end room) from which rim-of-mine coal has been extracted A supported method of underground coal mining in which coal is extracted from a rectilinear network of bords. with pillars of intact coal left in place to support the roof. (synonyms pillar-and-stall. room-tuul-pillar. sioop-and-room)... 

Colliery Culm bank Deep mine Diming Coal mine, especially an underground mine for coal See spoil heap See underground mine Excavation of tloor strata below a thin coal seam to improve the overall working height of roadways, thus improving access (see also ripping)... 

Figure 3 summarizes the principal environmental compartments that can in theory be affected by coal mining, as well as the principal potential environmental stresses that can arise from active and abandoned mine voids on the one hand, and from mine waste management facilities (i.e., spoil heaps and washery finings ponds) on the other. Further details on the mechanisms and impacts of these environmental stresses are given in Table 4 (for coal mine voids) and Table 5 (for coal mine wastes). 

Emitted from burning zones within spoil heap... 

For abandoned opencast sites, and for large spoil heaps associated with underground coal mines, landscaping and revegetation are clearly the key to long-term prevention of dust entrainment by the wind (see below). 

Fig. 4. Two contrasting spoil heaps in the Gardanne Coal Basin, Provence, France (a) Unrestored heap near Domaine de la Salle, showing largely bare spoil with characteristic development of scree and rills (cf. Nicolau 2002), with the only vegetation being a few self-seeding Mediterranean pines (b) Restored, thoroughly afforested spoil heap at Meyreuil, barely recognizable as a former mine waste disposal site.

Although the challenges and methodologies are essentially the same in both cases, the term reclamation is typically applied to applications concerning spoil heaps formed by deep mining operations, whereas restoration is the preferred... 

Tuck (1993). in terms of mine wastes, pyritic mudstone roof strata removed from the mine as part of routine ripping operations were deposited in substantial spoil heaps at Shilbottle Grange Pit and (to a lesser extent) at Whittle. The highly visible pyrite content of the Shilbottle spoil earned the heap at that site the local sobriquet of the Brass Heap ( brass being a dialect name for pyrite). 

Mature Whittle drift borehole Whittle recharge water Spy Law borehole Shilbottle Grange spoil heap leachate... 

BELL, F. G. 1996. Dereliction colliery spoil heaps and their rehabilitation. Environmental and Engineering Geoscience, 2, 85-96. 

Frouz, J. 2002. The effect of soil microfauna on litter decompostion and soil organic matter accum-mulation during soil formation in spoil heaps after brown coal mining. Ekologia-Bratislava, 21, 363-369. 

Pizl, V. 2001. Earthworm succession in afforested colliery spoil heaps in the Sokolov region, Czech Republic. Restoration Ecology, 9, 359-364. 

Rapid failures of colliery spoil heaps in the South Wales Coalfield. Quarterly Journal of Engineering Geology, 29, 103—132. 

Taylor, R. K. 1973. Compositional and geotechnical characteristics of a hundred year old colliery spoil heap. Transactions of the Institution of Mining and Metallurgy (Section A), 82, A1 - A14. 

Taylor, R. K. 1975. English and Welsh colliery spoil heaps - mineralogical and mechanical relationships. Engineering Geology, 9, 39-52. 

Loredo, J., Ordo nez, A., Gallego, J.R. et al. (1999) Geochemical characterisation of mercury mining spoil heaps in the area of Mieres (Asturias, northern Spain). Journal of Geochemical Exploration, 67(1-3), 377-90. 

But not only mercury is released by mining. Mn ore mining activities taking place in the Brazilian Amazon basin as open pits (for instance in the Serra do Navio, Amapa State), represent a potential source of associated ferrous metals (such as Ni, Cr, Cu, As). Acid mine drainage contains dissolved and particulate metals in toxic concentrations, affects the pH of streams and mobilizes metals. Moreover, wind dispersal of material from unstable spoil heaps can result in local or regional atmospheric contamination. Despite the likely importance of this source in the environment, it is currently not possible to estimate the quantities of trace... 

Plate 5.1 Excavations for copper at Parys Mountain, Anglesey, UK. The spoil heaps provide a huge surface area for sulphide oxidation. The lake waters in the pit bottom have pH below 3. Photograph courtesy of J. Andrews. 

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