Assessment of heavy metal contamination in groundwater of Diyarbakir Oil Production Area, (Turkey) using pollution indices and chemometric analysis

The study was conducted to determine the situation in terms of groundwater heavy metal contamination at 18 sampling stations close to the Diyarbakir Oil Production Area in Turkey. The heavy metal contamination indices were used during the assessment process. To further investigate the potential sources of heavy metals, multivariate statistical techniques were applied. Concentrations of heavy metals were found to decrease as: Cd > Mn > Fe > Pb > B > As > Zn > Al > Se > Hg. In the diagram of pH and metal load, the majority of samples (88.89%) were classified as “near neutral–low metal.” In general, the study’s results showed the groundwater HPI value to be lower than the critical value of 100. Based on the HPI values, 100% of the samples were classified as having a “medium” level of pollution. The HEI results showed that 83.3% of the samples were classified as having a “medium” level of pollution, and 3% as “low.” The Cd (contamination index) results revealed that all of the samples in the study area were found to be substantially “high” in their level of heavy metal pollution. The study’s factor analysis found that seven factors explained 79.2% of the total variation in the data. In the cluster analysis, good outcomes were seen with three different similarity groups. These results show that the factors responsible for heavy metal pollution primarily relate to oil exploration-production activities, mining, industrial and domestic waste disposal, agricultural activities, as well as being of geogenic origin.