The network of historical mines in Sardinia: a methodological approach for the restoration and the enhancement

The development of mining in Sardinia between the XIX and XX century has brought important changes at the local level in terms of economic, landscape and architectural involving not only local communities but giving a new impetus to Sardinia. The location of settlements, linked to the mineralogical and petrographic nature of the subsoil, coincides, in almost all cases, with the mining sites from Roman times. Mining activity has resulted, in the regional context, different ways to settle in the territory, related to the presence or not in the vicinity of consolidated residential areas. Therefore, it is possible identify settlements with a strictly mining function (wells, washery, etc.), or production complexes that include all the functions necessary for the development of micro-society (hospitals, schools, churches and cemeteries, structures for the recreational club). Both models have led to the creation of new infrastructure networks, one is the railway line, with a greater impact, closely linked to the production, linking the extraction sites to the main ports of the Island, and a secondary, with the purpose of connecting the mining villages with neighboring towns. The present study shows, in the first analysis, that the mining sites of the island have specific characteristics, well identified, on the basis of some specific parameters such as, in the first place, the orography of the land and the extracted raw materials, as well as the process of processing that derives from it, but also the construction period and the duration of mining activity, the changing needs of use and the resulting transformations that this entailed. A second aspect examined, resulting in this first analysis, is related to the state of conservation of this heritage of industrial archeology. Following the cessation of mining activity, in the second half of the twentieth century we saw the gradual abandonment of establishments, putting at risk the preservation of these historic buildings. The advanced state of deterioration and instability has resulted, in more severe cases, that these structures became ruins; today strongly characterizing the landscape as the only human sign in the context. Can be identified other vulnerability factors for these goods, In addition to the constant lack of maintenance that is not for decades, such as the position in relation to the coast, where the microclimate accelerates the process of deterioration of building materials. To ensure the preservation of these structures, beyond the single restoration, there must be a VIth Conference “Diagnosis, Conservation and Valorization of Cultural Heritage” 10/11 December 2015 264 re-use that ensures a constant fruition. The factors that hinder this process are many, but certainly one that most affects relates to the costs of reclamation of brownfield sites, severely affected by mining activities. In addition, to allow the territory to regain possession of these areas, it is necessary to activate or restore the infrastructure network which ensures easy accessibility. A final aspect to consider is the problematic reuse of such complexes, which are difficult to adapt to different functions of use compared to the original, because the spaces are specifically designed for the various phases of work. The goal of the research is to identify a strategy of restoration, new functions and therefore enhancing, from the architectural scale to the regional scale.