Investigation of groundwater chemistry of the Erzincan plain aquifer

This study, conducted in the Erzincan plain located in the Upper Euphrates basin of the Eastern Anatolia Region, aimed to investigate the groundwater chemistry of the plain aquifer. Erzincan plain and aquifer area were shaped under the influence of natural factors such as earthquakes, landslides, avalanches and floods. The effects of these factors on the plain continue today. Surface and groundwater in the study area show different hydrogeological and geochemical characteristics depending on the surface shapes formed due to the active tectonics of the region, the mineralogical properties of the sediments forming the plain aquifer, the lithologies in the groundwater recharge areas and anthropogenic effects. Due to these effects, the quality of surface and groundwater also changes. This change develops depending on the geochemical properties of the source rock, secondary mineralization in fault zones, and human activities carried out in the environment. Within the scope of the thesis, a total of 100 water samples were taken, 48 from the surface waters of the Erzincan Plain and 52 from the groundwater. With the samples taken, toxic metal analyses, major anion - cation analyzes and physical properties (Eh, Ei, PH) of the water were determined. According to the analysis, the maximum and minimum values of heavy metals were obtained within the ranges of: Al; 4496,89 / 21,91 ppb, As; 65,47 / 0,39 ppb, Cd;17,43/0,02 ppb, Cr;341,18 / 0,47 ppb, Cu;788,38 / 1,75 ppb, Fe;4313,41 / 39,44 ppb, Mn;2986,69 / 1,22 ppb, Ni; 2230,09 / 7,84 ppb, Pb; 48,68 / 0,65, Zn;5174,48 / 7,63 pbb. The results obtained were evaluated according to the limit values determined by international organizations (ITASHY, EPA, WHO). It was determined that the element concentrations of As, Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in some samples were higher than the drinking water maximum/minimum limit values specified in international standards (ITASHY, 2005; EPA, 2009; WHO, 2008). has been made. According to the results of major anion - cation analysis, it has been determined that the origin of the region's waters is of ophiolitic and Limestone (CaCO3) origin, depending on the activity of the North Anatolian Fault system, which limits the geological and study area of the region from the north, and its general classification is magnesium bicarbonate waters. It has been determined that the waters of the region are in the C2-S1/C3-S1 class according to the US salinity classification, in the S1 class according to the Sodium Adsorption Rate classification, and in the usable water class according to the Permanent Sodium Carbonate classification.