Delle Rose M.,, 2007, The 29 March – 1 April 2007 Gallipoli collapse sinkhole evolution (Lecce province, Italy) and related Civil Protection management., Epitome (Udine) 2 (2007): 243–244.,
URL: http://www.cnr.it/prodotto/i/118248

Civil Protection is a major component of any society which must improve the level of safety and protection of its citizens. The role of the Research Institutions and especially the Competence Centre of the Civil Protection system of Italy, is to develop the activities about the hydrogeological damages and to guarantee a scientific consultation service of prediction and prevention of the calamitous events also during the emergencies. According to the Protection Civil Department database, Apulia is the fourth region in Italy affected by sinkholes, the greatest part of which due to collapse of mane-made cavities. The Salento peninsula, i.e. the southern part of the region, had hosted in the last twenty years at least fifteen events of sinkholes the last of which occurred at Gallipoli to start from 29 March 2007. The town of Gallipoli is located along the Ionian coast of the Lecce province, on a Quaternary succession which represent an international stratigraphic reference at least from the beginning of the XX century. The top of this succession is formed by calcarenitic units intensively quarried as building stone probably from ancient age. The extractive activities have made several wide underground quarries on which the town had been extended during the last decades. Voluntary associations, such as the Gruppo Speleologico Neretino, have mapped some underground quarries in the last twenty years. Some years ago, small and little damaging episodes of sinkholes were occurred but they did not consider enough to start an adequate vigilance system. The degree of event starts the 29 March had instead been so high to force the emptying of the house of more than one hundred peoples. As precursor signal, a sewage manhole was deformed and shifted. A first collapse had created a 12 x 18 m sinkhole, with the top of the cone shaped deposit deep about 3,5 m, which intersected the base of two 3 floors buildings. However, some adjacent constructions might been involved by a enlargement of the sinking. The observation of the fissure affecting the building revealed that a subsidence phenomenon had begum at least some months before the sinking. The underground area was explored together with the SAF Fireman Groups and the results were exposed to the Crisis Unit constitute to manage the first Civil Protection action. The state of incipient enlargement of the sinkhole as well as its unpredictable evolution were discussed. In particular, the widespread of calcarenites crevices due to opening of tectonic fractures, the presence of crushing fractures at the base of the columns holding the vaults of the quarries and the worrying thin thick of the quarries roof were showed. Against these evidences, filling operations of the sinkholes were decided after the Crisis Unit meeting. The 1 April 2007, during the laying of cement and stones, a further collapse had approximately triplicate the sinkhole crater area but fortunately it did not cause any victims. The experience of this disaster management can suggest some improvement of the Civil Protection Regulatory Frame. First of all, the safety and protection of the human life must be guaranteed not only for the resident peoples but also for every persons operating within the disaster scenarios, and especially the workers attending in emergency constructions that lacking of appropriate engineering projects. Furthermore the constructions achieved during the hydrogeological damage, made to attempt to limit the harms of building, could not impede further geological surveys that need to check safe carrying capacity and stability of the subsoil. Eventually, significant progress is possible if long-term action is engaged on the basis of broad cooperation. The advanced research can provide solid scientific and technical basis for regulation, the development of disaster prediction procedures, and the best possible management of the crisis situations.

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