Assessment of groundwater quality around Erbil oil refinery in Northern Iraq

Groundwater is one of the world's most vital freshwater sources, essential for drinking, agriculture, and industry. It supplies nearly one-third of the global population's water needs and plays a crucial role in sustaining ecosystems , As urbanization and industrialization expand, particularly in developing regions, pressure on groundwater systems increases, making its protection an urgent priority. Industrial activities, especially oil refining, pose a major risk to groundwater quality. Refineries generate numerous contaminants, including hydrocarbons, heavy metals, and organic solvents. These can seep into the soil and leach into aquifers, altering groundwater chemistry and threatening both human health and environmental stability. The proximity of refineries to aquifers increases the risk, especially if spills or improper waste disposal. This study was conducted to assess the water quality of groundwater wells in Erbil Oil Refinery in Northern Iraq under potential pollutant pressure from some industries. The Water Quality Index (WQI) was used to evaluate the results of the water quality monitoring study. Also, representing the mechanism controlling of groundwater quality and classification of groundwater. WQI map elements distribution map from spatial distribution interpolationInverse Distance Weighted (IDW) in ArcGIS platform were used to evaluate the results. Results indicate varying water qualities. Throughout the study period, the water quality at the Erbil Refinery generally fell within the range of "Poor to good" for groundwater systems from S1 to S22, with a CWQI range of 42.39-92.14. The findings show that the rock-dominant effected the quality of groundwater. However, Piper and Schoeller classification representing groundwater water quality type was (Ca-Mg-SO4-bicarbonate water type). Also, from the CWQI analysis indicate that the water quality in areas distant from the Erbil Refinery, as well as in collectives and villages such as S5, S6, 7, S20, S21, S18, and S2, was found to be satisfactory and good. The degradation of water quality has been seen at various sites in close proximity to the Erbil Refinery, including S1 (Inside the Refinery boundary), S14, and S16, as well as in areas near settlements such as S4 and S8. The observed phenomenon could potentially be attributed to the escalating contamination of untreated water sources, including urban trash, precipitation, and human-induced activities and might be the refinery effect. There are still certain places, namely S2, S3, and S15, that have a favorable water quality index and are in close proximity to facilities. In general, the groundwater quality in the vicinity of Erbil Oil Refinery seems to be appropriate for drinking, while there are a few specific areas that need more monitoring and remediation measures to guarantee the long-term safety of the water.