Developing rehabilitation design for the abandoned mine excavations in Central Sardinia, Italy

In central Sardinia several talc-chlorite-feldspar bodies have long been mined by open-pit operations. The mining activity has deeply modified the original landscape of the Lasasai-Bonucoro area in the district of Orani. Thus the rearrangement of this area, in particular the open-pit works that are now occupied by pools filled with ground water from aquifers, should be considered as an overall project of landscape restoration. Particular conditions, such as the constant outflow of good-quality water and the amenity of the surrounding countryside, are favourable to the accomplishment of the recovery plan. The GPS tool is particularly suitable in projects of open-pit recovery to make highly accurate topographical maps by geodetic measurements thus forming the backbone of a project. On the basis of the naturalistic and geographical contexts of the mining area and its surroundings, a few proposals concerning the re-utilisation of these excavations are here presented. The preparatory work consisted of characterization of the study area with a topographic survey, establishment of a geodetic control network with GPS to describe the morphologic features of the landscape, and the representation of the study area using three dimensional analysis and geoprocessing by commercial GIS/CAD software. The final step is represented by the use of a Digital Scenery Generator (DSG) that is capable to integrate graphical data layers with geological and morphological maps enabling the creation of virtual 3D environments thus giving a rendering of a present, past or future landscape development allowing for visual impact assessments.