Investigation on groundwater pollution of Shazand refinery with BTEX and MTBE

Abstract

Shazand oil refinery, as the biggest producer of gasoline in the Middle East, is located 22 km to the Southwest of Arak and the Northeast of Shazand plain. Due to presence of various storage tanks of crude oil and oil products, processing unites and conveyance lines of oil products, it is very possible the leakage of pollution from tanks and conveyance lines into the soil and groundwater. Shazand plain aquifer is an unconfined and consists of coarse-grained alluvial deposits with a flow direction from the refinery to the agriculture wells which are located at the center of plain. Hence, groundwater contamination, which was resulted from the oil pollution of Shazand refinery was investigated. In this study, 16 wells were sampled in study area on Jun 2015 and they delivered to laboratory for analyzing. Compound BTEX and MTBE analyzed by gas chromatography with flame ionization detector (GC-FID4). To investigate contamination in study area, results of analyses of BTEX and MTBE were compared with valid standards of drinking and agriculture water. The results show that 6 wells are polluted at the East and South of refinery and the east and Northeast of petrochemical complex. A part of the groundwater contamination was due to atmospheric washout and the other part relates to leak from utilities, tanks and conveyance lines. Discussion & Conclusion: Considering the already existing and the other possible forms of contamination in the area, it is proposed that before taking, the exact source of contamination be identified and proper measures to clean the area be chosen based on expert opinion.