Abstract
Problem statement: The analysis of the relationships among the different hydrogeological Units and the assessment of groundwater quality are fundamental to adopt suitable territorial planning measures aimed to reduce the potential groundwater pollution especially in agricultural regions. In this study, the characteristics of groundwater dynamics and the assessment of its quality in the Cuneo Plain (NW Italy) were examined. Approach: In order to define the geological setting an intense bibliographic analysis has been performed by the authors. This analysis was implemented by several correlated land controls and specific surveys that have permitted to analyze to certain reliability the Quaternary evolution of the entire plain sector and the current relationships among the different geological bodies that strongly affect the groundwater dynamics. Results: The Quaternary alluvial deposits overlap a Tertiary sedimentary succession through a series of erosional unconformity surfaces. These Quaternary deposits highlight a variable thickness ranging from 80-100 m in the foothills of the mountains up to a few meters in the more distal portion of the plain. In these deposits there are several unconfined aquifers which are not hydraulically interconnected due to the deep fluvial incisions that reach the underlying tertiary substrate. The Cuneo plain is intensively populated and lot of villages and farms characterize the landscape. In the overall area it is present an intensive agricultural and livestock activity predominantly represented by crops of wheat and corn and farms of cattle and pigs. All these activities represent point and diffuse groundwater pollution sources and require a considerable amount of groundwater which is withdrawn from the Quaternary aquifers by means of thousands of water wells. The groundwater quality is strongly influenced by the content of nitrates and manganese. The nitrates are linked to pollution due to agricultural activities and livestock and increase along the groundwater flow lines. The manganese content is quite high in the foothills of the mountains and in some restricted areas of the plain and appears to be linked to the natural litho logical composition of the aquifers. Conclusion: Due to high degree of intrinsic aquifers vulnerability over the entire Cuneo plain sector in order to reduce the actual groundwater pollution and the risk for human health it has to be planned several territorial suitable planning actions aimed to limit nitrates effluents and livestock untreated discharges according with the European rules.
Highlights
To correctly assess the planning actions to be implemented in order to reduce the groundwater pollution risk, the hydrogeological setting and the groundwater dynamics have to be evaluated at an early stage of any territorial analysis (Bianchi-Fasani et al, 2011)
Due to the deepening of several waterways the plain was segmented into several different sub-areas. These rivers currently run embedded in the Miocene or Pliocene substrate, several tens of meters below the fundamental level of the plain (Fig. 3)
Hydrogeological setting and groundwater dynamics: In the Cuneo plain, several unconfined aquifers were identified. They are hosted into different hydrogeological Units and separated by extensive and continuous outcrops of the Miocene - Pliocene substrate sediments located along the river's deep cuts
Summary
To correctly assess the planning actions to be implemented in order to reduce the groundwater pollution risk, the hydrogeological setting and the groundwater dynamics have to be evaluated at an early stage of any territorial analysis (Bianchi-Fasani et al, 2011). The accurate analysis of the relationships among the different hydrogeological Units and the assessment of the groundwater quality are fundamental to adopt suitable territorial planning measures aimed to reduce the potential groundwater pollution by means of land use restrictions (Ashraf et al, 2011; Cheong et al, 2011; Hamilton and Helsel, 1995; Lo Russo and Taddia, 2009; Nouri and Malmasi, 2005). In the plain sector belonging to the Tanaro river catchment basin it is possible to observe a relatively recent rapid deepening of the main watercourse and its tributaries, which flow deeply in the plain. These phenomenons affect both the Quaternary alluvial deposits and the underlying Tertiary succession. Nitrate, one of the most common pollutants in groundwater, causes a significant water-quality issue
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call