ASSESSMENT OF GROUNDWATER QUALITY AND HYDROGEOLOGICAL PROFILE OF KAVALA AREA, NORTHERN GREECE THOMAS SPANOS 1 , ANTOANETA ENE 2,* , CHRISTINA XATZIXRISTOU 1 , AGELOS PAPAIOANNOU 3 1 Eastern Macedonia and Thrace Institute of Technology, Department of Petroleum and Mechanical Engineering Sciences, St. Lucas, 654 04 Kavala, Greece 2, * Dunarea de Jos University of Galati, Faculty of Sciences and Environment, Department of Chemistry, Physics and Environment, 47 Domneasca St., 800008 Galati, Romania; e-mail: aene@ugal.ro 3 Technological Educational Institute of Larissa, Department of Medical Laboratories, 41110 Larissa, Greece Abstract. In the present study thirty two representative sites have been selected for the collection of water samples from central water supplies in the region of Kavala, Northern Greece. Water source sites were identified depending on the geographical location. Seven physicochemical parameters (electric conductivity, chloride, sodium, total hardness, total alkalinity, bicarbonate and calcium) were analyzed monthly, in the period from January 2010 to December 2010. Hierarchical cluster analysis grouped the 384 cases (32 x 12) of observation into three clusters (1: coastal, 2: lowland and 3: semi– mountainous) based on the similarities of potable water quality characteristics specific to geological origin. The mean plots of variables (Ward’s method) allowed the membership assignment of each parameter in the three–cluster solution. The classification scheme obtained through cluster analysis was confirmed by ANOVA. The mean values of the studied physicochemical parameters were found to be within the limits given in the 98/83/EC Directive. The water samples are appropriate for human consumption. The results of this study provide an overview of the hydrogeological profile of water supply system for the studied area. Key words: Groundwater quality, Prefecture of Kavala, public health, hierarchical cluster analysis, ANOVA. 1. INTRODUCTION Groundwater is one of the most important major natural resources necessary for human consumption, domestic services, agriculture, industry, manufacturing and other sectors [1]. The quality of the groundwater receivers is influenced by pollution of soil and air, industrial and domestic waste disposal, organic components, pathogenic microorganisms, application of fertilizers and pesticides in agriculture, etc. [2-4]. In view of the importance for public health of water for human consumption, the European Union (EU) laid down various quality standards with which potable water must comply, establishing a number of Council Directives: 98/83/EC [5], 2000/60/EU [6], 2006/118/EU [7], that refer to the protection of the water resources and public health. Careful studies on the quality of water intended for human consumption could significantly contribute to the creation of a common strategy for potable water assessment [8]. During monitoring and assessment of water quality, large data sets could be collected, which contain rich information about the behavior of the potable water supplies and the potable water characteristics [1].