Assessing of Oil Refinery Plant Residues on Soil Contamination in Kasnazan District – Erbil, Iraqi Kurdistan Region

Abstract

This investigation conducted on April 01, 2015, of the different locations surrounding oil refinery factories near the Kasnazan district on Sulaimani road (Latitude 36.211N, Longitude 44.157E), to assess the effects of oil refinery factory residues on soil contamination. Soil samples were collected towards (E and W) from the contamination source, with various distances (0.5, 1, and 1.5 m) and different depths (0–10, 10–20, and 20–30 cm) consequently. The concentrations of heavy metals such as chromium, iron, manganese, nickel, and zinc were sequentially extracted and measured using portable X-ray fluorescence at the soil and water department laboratories. The heavy metals concentration of the soil samples was significantly affected by both factors (distances and depths). Fe had the highest concentration value as ranged from 486.0 to 520.2 mg/kg with a mean (502.9 mg/kg), while Cr and Zn had the lowest concentration value, Cr ranged from 0.0 to 9.33 mg/kg with a mean (3.22 mg/kg) and Zn ranged from 0.0 to 1.9 mg/kg with a mean (1.43 mg/kg). Mn concentration ranged from 9.6 to 13 mg/kg with a mean (11.55 mg/kg) and Ni concentration ranged from 4.3 to 10.03 mg/kg with a mean (7.40 mg/kg). The geoaccumulation index values of most samples located under the class (1) uncontaminated to moderate index.