Subsidence hazard connected to quarrying activities in karst area: the case of the Moncalvo sinkhole event (Piedmont, NW Italy)

Gypsum is an important raw material for constructions and other industrial sectors. In Piemonte (NW Italy), main gypsum bodies are located in the Monferrato area where big open pits and underground quarries are present. The gypsum bearing formation outcropping in this area show typical geological, structural and hydrogeological features which influence quarrying exploitation and the relative interaction with natural phenomena, humans activities and land uses. In particular, gypsum karst has a considerable influence on mining operations, as well as mining operations can produce strong impact on gypsum karst. In Monferrato, a specific case of interaction between quarrying activity and geological, hydrogeological and territorial setting is represented by the event of water inrush happened in the Moncalvo underground quarry associated to the development of a surface sinkhole phenomenon.