Delineation of Protection Zones for the Main Discharge Area of the Gran Sasso Aquifer (Central Italy) through an Integrated Geomorphological and Chronological Approach

Abstract

The paper proposes a study for the delineation of protection zones in the main discharge area of the Gran Sasso aquifer (Central Italy). At this aim, starting from a detailed geological and hydrogeological reconstruction, the study was divided into the following phases: 1) development of a conceptual model of water flow in the study area; 2) creation of a 3D numerical model in order to simulate the groundwater flow in saturated conditions, both at the basin and at fine-scale; 3) flow path analysis through deterministic and stochastic approaches; 4) assessment of the aquifer vulnerability based on a geomorphological analysis of the catchment area. Conceptual and numerical models were then used to delineate protection zones for wells and springs with chronological criterion and geomorphological-structural criterion (based on the EPIK method). The results show that with a chronological approach protection zones are located along the main flow directions, corresponding to the areas surrounding wells and springs with high hydraulic conductivity values (faults and thrusts) within the satured zone. On the contrary, the geomorphological method has found some important protection zones also quite far from wells and springs, in areas characterized by quick infiltration processes. The protection zones delineated with the stochastic method were finally intersected by the vulnerability map obtained with the EPIK method, to take into account both filtration and infiltration processes. The results show the local vulnerability of the groundwater to the pollution, with protection zones extending 1 to 5 km towards northeast from springs and wells.

Hydrodynamic Characterization of Carbonate Aquifers Using Atypical Pumping Tests without the Interruption of the Drinking Water Supply

“…Locally, the geological and hydrogeological framework is quite complex because of the heterogeneity of the deposits; Figure 2 shows the detailed hydrogeological set-up of the study area, from the literature data and available borehole stratigraphies [37][38][39][40]. The Gran Sasso carbonate complex is in contact with the marly-clayey one, creating a no-flux hydrogeological limit.…”

Hydrodynamic characterization of carbonate aquifers by atypical pumping tests without interruption of drinking water exploitation

“…Locally the geological and hydrogeological framework is quite complex because of heterogeneity of the deposits; from literature data and available boreholes' stratigraphies [15][16][17][18], in Fig. 2 the detailed hydrogeological set-up of the study area is shown: the Gran Sasso carbonate complex is in contact with the marly -clayey one creating a no-ux hydrogeological limit.…”

Short review of some methods for groundwater flow assessment in fractured rock masses

“…Kazemi (1969) proposed a method to estimate the main hydrogeological parameters of dual permeability aquifers, whereas for anisotropic aquifers the most commonly used methods have been developed by Papadopulos (1969), Fig. 5 -Example of hydrogeological map, in which the type of permeability (and then the type of aquifer) and the main groundwater flow direction is defined (Biava et al 2014).…”

“…Fig. 5 -Esempio di carta idrogeologica, nella quale vengono definiti i tipi di permeabilità (e di conseguenza la tipologia di acquifero), nonché le direzioni di flusso principali (Biava et al 2014). Hantush (1966) and Neuman et al (1984).…”