Ranking of pesticides according to leaching potentials to groundwater for the selected river basins in turkey – index-based approach


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Çevre Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2016

Tezin Dili: İngilizce

Öğrenci: AYŞE ECE AKAY

Asıl Danışman (Eş Danışmanlı Tezler İçin): Ülkü Yetiş

Eş Danışman: Filiz Bengü Dilek

Özet:

Recently, identification of pollutant parameters in river basins of Turkey has been greatly concerned by the Ministry of Forestry and Water Affairs (MoFWA).In this respect, the intention of MoFWA is to identify the pollutants which would be included in monitoring programs as required by the regulations toward the protection of water sources, both surface and groundwaters. Among these identified pollutants, various pesticides appeared as important group of pollutants to be monitored. Given the fact that pesticides in the aquatic environment are present at very low concentrations which necessitate sensitive analytical methods and analytical instruments in favor for determination, the pesticides having the high leaching potential to the groundwater were tried to be identified to be included during the groundwater monitoring programs, rather than monitoring whole pesticides. The intention was to minimize or avoid unnecessary measurements and in turn to prevent costly monitoring programs. Therefore, in this study, it is aimed to perform pesticide groundwater leaching potential assessment with prioritizing the pesticides for the selected river basins of Turkey, namely, Akarcay, Büyük Menderes, Meric-Ergene, Gediz, Kızılırmak, Kücük Menderes, Konya Kapalı, Sakarya and Susurluk, that would contribute to the efforts of Ministry of Forestry and Water Affairs (MoFWA) for identifying the pesticides to be included during the groundwater monitoring studies. Considering the approaches applied by European Union (EU), USA and international organizations intended for the identification of the pesticides having potential of leaching to groundwaters, it was decided that index-based approaches which generally ground on pollutant and soil properties are most suitable for conditions of Turkey meaning data availability. It was observed that index-based approach has been applied for pesticides in both EU and USA in the first step. These indices fundamentally evaluate the leachability and can be regarded as a risk assessment for groundwaters. The prioritization study was performed for 157 pesticides. For all of these pesticides, 18 different indices were calculated. It was realized that some of these indices give different results that make ranking of pesticides difficult. For this reason, a new index named as YASGEP-P was developed by applying Principal Component Analysis (PCA) with combining the evaluated indices. With taking YASGEP-P as basis, 6 priority groups were obtained. First two groups among the 6 groups resulted from prioritization of pesticides were decided to be included in groundwater monitoring studies as a priority. In addition, “pesticides included in the list of 45 priority pollutants” determined through Water Framework Directive (WFD) are the pollutants that should be definitely monitored, so they were also included separately in the pesticide list for the groundwater monitoring.