1. HAO-Demeter, Agricultural Research Institution of Crete, 71300 Iraklion, Greece and Union of Hellenic Water Supply and Sewerage Operators, Larissa 41222, Greece
2. Laboratory of Engineering Geology and Hydrogeology, Aristotle University of Thessaloniki, Thessaloniki, Greece
3. Department of Civil and Environmental Engineering, University of California at Davis, Davis, CA 95616, USA