Site characterization and monitoring of natural attenuation indicator parameters in a fuel contaminated coastal aquifer: Karaduvar (Mersin, SE Turkey)

Abstract

This paper presents results from a site characterization and monitoring study at Karaduvar area (Mersin, SE Turkey), where high concentrations of refined petroleum products have been detected in domestic and irrigation water wells. The saturated and unsaturated zones in the deltaic aquifer are contaminated by large quantities of gasoline and diesel range fuel hydrocarbons (GRHs and DRHs) released from diverse sources that include accidental spills, storage tank fires, pipeline breaks, deliberate discharge of waste petroleum products from slop tanks and illegal tanker truck washing facilities. At the site, due to the complex nature of the pollution sources, overlapping contaminant plumes exist and cover an area of about 0.5 km 2 . In both polluted and unpolluted parts of the aquifer, monitoring of groundwater physicochemical parameters in a total of 55 sampling points was carried out between 2006 and 2007. The results show that the terminal electron acceptors (e.g. dissolved oxygen, nitrate, Mn(IV), Fe(III), sulfate) were reduced near the source area(s) indicating presence of actively operating biodegradation processes at the site. Close to the contaminant source area(s), conditions in the plume are highly anoxic and reducing; where high amounts of transformation products (e.g. bicarbonate, dissolved iron, and manganese) are present in solution. Additionally, at the site, excessive pumping, careless land use, and deliberate wastewater discharges significantly deteriorated the quality and quantity of groundwater. Excessive groundwater pumping for industrial and agricultural uses has resulted in substantial water level declines (2-3 m) near the coastal part where seawater intrusion threatens the groundwater resources.

Seasonal and Spatial Variability of Anthropogenic and Natural Factors Influencing Groundwater Quality Based on Source Apportionment

“…The natural weathering and dissolution processes of the minerals are mainly responsible for the release of Fe and Mn; however, their activities are mostly controlled by the redox level of groundwater. The high concentrations of these elements were likely due to reductive dissolution of Fe/Mn oxides found in aquifer sediments [ 46 ]. This reducing environment was beneficial to the Fe and Mn contamination in upper layer of muddy loam and clay ( Figure 1 ).…”

Processes Governing Alkaline Groundwater Chemistry within a Fractured Rock (Ophiolitic Mélange) Aquifer Underlying a Seasonally Inhabited Headwater Area in the Aladağlar Range (Adana, Turkey)

“…Additionally, snow samples were collected shortly after two major snowfall events on January 2012 ( = 6) and February 2013 ( = 5) from various locations of the site for physicochemical characterization of the precipitation. Sampling and analytical techniques followed the suggestions by APHA-AWWA-WEF [65] and were similar to those described earlier in the literature [1,66]. The field parameters (pH, redox potential (Eh), dissolved oxygen (DO), electrical conductivity (EC), and temperature) were measured in situ using a WTW Multi 340i/SET multiparameter instrument (Wissenschaftlich-Technische Werkstätten, Germany).…”

Deliçay ile Tarsus (Berdan) Çayı Arasındaki Bölgede Yer Alan Kuvaterner Sedimanlarının Mineralojik ve Jeokimyasal Özellikleri

“…Çalışma alanı ve yakın civarının jeolojik haritası (Şenol vd., 1998(Şenol vd., ve Güler vd., 2009. Şenol et al, 1998 andGüler et al, 2009). …”

“…Bu çalışmada, kıyıya yakın bölümlerde hakim tane boyunun kum olduğu, buna karşın kıyıdan uzak kuzey bölümlerde ise kil ve silt boyutunda malzemelerin ağırlık kazandığı belirtilmektedir. Bölgede genel jeolojik amaçlı (Çavuşgil, 1985; Şenol, 1989; Şenol vd., 1993; 1998) ve toprak kirliliğine yönelik çok sayıda çalışma vardır (Topak, 1997;Aysan, 1999;Köleli ve Halisdemir, 2005;Kurt vd., 2008;2009b;2009c;Güler, 2009). Buna karşın bölgedeki delta çökellerinin mineralojik bileşim ve jeokimyasal özellikleri ile ilgili kapsamlı bir çalışma bulunmamaktadır.…”