Présentations Colloques

Poster
8.08
Session 8.08: Mineral and Thermal water: an indicator of deep processes and source of economically valuable minerals
Meerkhan (orateur)
Groundwater vulnerability assessment in fractured rock hydromineral systems (Caldas da Cavaca, Central Portugal)
Assessing groundwater vulnerability is often done through GIS technologies. GIS has become a useful tool to generate vulnerability maps and for simple testing of methods of display. Groundwater protection for human activities with suitable quality makes necessary to determine source protection zones for watersheds in hard‐+rock hydromineral systems to protect them from several risks of contamination.**This study intends to develop a groundwater vulnerability approach in Caldas da Cavaca hydromineral system (Aguiar da Beira, Central Portugal), which has a thermal tradition for almost two centuries, and to contribute to improve the hydrogeological conceptual site model.**In this work different layers were overlaid, generating several thematic maps to arrive at an integrated framework of several key‐+sectors in Caldas da Cavaca site. Thus, to accomplish a comprehensive analysis and conceptualization of the site, a multi‐+technical approach was used, such as, field and laboratory techniques, where several data was collected, like land use, geotectonics, hydrology and hydrogeomorphology, hydrogeology and hydrogeophysics. All these techniques were successfully performed and a groundwater vulnerability to contamination assessment based on DISCO index methodology was delineated.**DISCO method indicated that the zones surrounding the hydromineral wells fit in a high vulnerability class, while the rest of the area fits in a low vulnerability category. DISCO index is in general accordance with other vulnerability indexes previously studied in this site (namely, DRASTIC‐+Fm and SINTACS).**Moreover, most of the high vulnerability groundwater protection zones, defined with DISCO method, include the immediate and intermediate wellhead protection areas previously established in 1996 by the Portuguese legislation for Caldas da Cavaca spa.
Portugal