Evaluation of hydrogeochemical properties and usability potential of surface and ground waters in Safaalan (Tekirdag–Saray) region

This study is submitted to Istanbul Technical University Institute of Science and Technology as a master thesis and covers to research the effects of inactive coal areas on surface and ground waters as the potencial of usability water quality in Safaalan Village (Tekirdağ - Saray) and its surroundings. In 1992, coal mining started by TKI in the study area and its ended in 2002. After the ending of mining, five lakes (Between 0,006 and 0,04 km2) were formed in the area. The main subject of this study is to research the effects of inactive coal areas on lake waters physicochemical parameters which is identified in site and the laboratory. To identify Safalan Villiges and the surrounding 's geological structure and to create the geology map of the region, the study was conducted in the area. In the a stratigraphycal sequence of the area, the oldest unit is the Upper Eocene – Lower Oligocene Soğucak Formation, middle – Upper Oligocene Çakıl Formation, Middle – Upper Miocene Ergene Formation, Upper Miocene – Lower Pliocene Kırcasalih Formation, and the youngest unit is the Quaternary aged alluvial deposits. In this study, the main subject of this study is to research the effects of inactive coal areas on surface and ground waters in the study region. With this aim, 20 surface and subsurface waters were sampled in wet season (March 2015) and dry season (August 2014). 9 of these samples represent wet season, 11 of them represent dry season. The samples are taken from lakes (5 + 4), taps (4 +3) and wells (2 + 2). Heat, pH, Eh, conducdivity (EC), salinity (NaCl), acidity, alkalinity and dissolved oxygen (DO) values were identified on site; whereas, ingredients of main and trace elements were identified in the laboratory. The value of pH is important for drinkable waters. The sampled waters pH value in the study area in the limit values set by TS266 (6,5 – 9,2). The EC values of the waters which means waters total ion are belowed the limited value by TS266 (2000 μS/cm). The all samples of lake waters and two of taps in dry season are exceeded the heat limit values set by TS266 (25 ºC). The waters main anion (Cl-, SO4=, HCO3-) and main cation (Ca++, Mg++, Na+, K+) values are identified; the tap and wells water samples values are in the limit values, the lake water are determined as usable water (clean, cook and irrigation) because of the values. The waters are adapted to Riverside Diagram for irrigation, and the waters determined as Less Salinity Water. Also Wilcox diagrams are prepated, and the water determined as Very Well – Well Waters and Well Waters. To prove the relationship between waters chemical components and lithology, the semi-logarithmic Schoeller Diagrams are prepated. The cation permutations of waters are rCa+2> rNa++rK+>rMg+2 (%55) and rNa++rK+ > rCa+2> rMg+2 (%45), the results are parallel with the main formation of the area is Ergene Formation. The anion permutations of waters are rC1- > rHCO3- > rSO4= (%50), rHCO3- > rC1- > rSO4= (%30) and rC1- > rSO4= > rHCO3- (%20). HCO3- values are higher than Cl- and SO4- values on some permutations, it is related with Ergene Formations heterogeneous lithological components and Safaalan Regions carbonate units. The waters high SO4- and Cl- values are can explained by widespread clay units and the absorbation capacity of clays. The water samples were analyzed for trace elements by ICP – MS methods for 72 elements. Al, As, B, Ba, Be, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb are considered to pose threat to health, Mn, Fe and Al values are determined exceeded the limit values of drinkable waters. As the all data derived are evaluated along, the ground water of Safaalan Villige and its surroundings are located in one of the most important coal areas which is called as Trakya Havzası in Turkey, is determined as drinkable waters without the high value of Ç5, Ç6, Ç7 and K9. The lake waters SO4- (sample G13), Cl- (samples G13 and G14), Mn+2 (sample G15), Fe+2 (samples G13 and G15) and Al (samples G13 and G15) values are exceeded the limits. The all samples are determined as usable water and irrigation waters and the waters of the area are proved not to constitute a negative effect in this respect.