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Water is an essential economic and social resource. It is also finite and vulnerable. For Europe, this generally accepted understanding has been translated into the European and National Directive (2000/60/EC, D.Lgs. 152/2006). This law has led to an increased awareness of the role of the resource and its importance in the socioeconomic, cultural, and political realms. To protect this resource, safeguard zones for drinking water sources must be delineated. In Italy, a drinking water source such as a well or spring is to be protected by means of a three-level safeguard zone: an absolute safety zone close to the source, a respect zone depending on groundwater travel time, and a Protection Zone. The aim of this paper is to describe an integrated methodology used to define the Protection Zone. The work, developed within the framework of a project of the Institute of Geosciences and Earth Resources (IGG-CNR) and funded by the Tuscany Region Administration through “Consorzio Lamma”, focused on the delineation of the Protection Zones for several abstraction points located throughout the regional territory. The proposed methodology for protecting drinking water sources described in this paper integrates geological, hydrogeological, and hydrogeochemical methodologies. The approach includes a definition of the hydrostratigraphy of the aquifer systems, estimates of the water volume, and the quantification of inflows and outflows, as well their interrelationships. By means of this integrated methodology, fifteen Protection Zones were defined; each of these zones was divided in two areas according to their relative importance to supplying a drinking water source. The Protection Zones were further validated by means of hydrogeological and isotopic budget calculations.

In this study the new Regional Geochemical Database (RGDB), called GEOBASI, is presented and illustrated in the framework of a joint collaboration among the three Tuscan universities (Florence, Pisa and Siena), CNR-IGG (Institute of Geosciences and Earth Resources of Pisa), ARPAT (Regional Agency for the Environmental Protection), LAMMA (Environmental Modelling and Monitoring Laboratory for Sustainable Development) Consortium and S.I.R.A. (Territorial and Environmental Informative System of Tuscany). The database has permitted the construction of a repository where the geochemical information (compositional and isotopic) has been stored in a structured way so that it can be available for different groups of users (e.g. institutional, public and private companies). The information contained in the database can in fact be downloaded freely and queried to correlate geochemistry to other non compositional variables. The first phase of the project was aimed at promoting the use of the geochemical data already available from previous investigations through a powerful Web-GIS interface to implement the exploratory statistics graphical-numerical tools used to: 1) analyse the spatial variability of the investigated context, 2) highlight the geographic location of data pertaining to classes of values or single cases, 3) compare the results of different analytical methodologies applied to the determination of the same element and/or chemical species, 4) extract the geochemical data related to specific monitoring plans and/or geographical areas, and finally 5) recover information about data below the detection limit to understand their impact on the behaviour of the investigated variable. Developments of this project will be focused on the definition of rules and standardized methods in a way that external users could also interactively pursue the RGDB. Furthermore, a detailed investigation of the Scarlino-Follonica plain will permit the improvement and test of statistical and geostatistical methods, using open source software (QGIS and R) to support the process of evaluation of the geochemical baseline.