Advanced Applied Geology

Advanced Applied Geology

The Role of Atmospheric Washout in the Transfer of Volatile Hydrocarbon Pollutants (VOCs) to Soil and Groundwater in the Assaluyeh Region

Authors
Mohadeseh Parvinisani 1
Abdorreza Vaezihir 2
Seyed Jafar Esmat Saatlou 3
Faezeh Nayeb 4
1 , Faculty of Natural Sciences, University of Tabriz
2 Dept. of Earth Sciences, University of Tabriz
3 , Islamic Azad University, Science and Research Branch, Tehran, Iran
4 Faculty of Natural Sciences, University of Tabriz, Tabriz
10.22055/aag.2025.49189.2502
Abstract
Groundwater and soil contamination by hydrocarbons and volatile organic compounds (VOCs) is a significant environmental challenge in petrochemical industries. This study implemented a comprehensive approach to assess potential contamination in a petrochemical complex located in Assaluyeh, Iran. The methodology involved designing, Excavating, equipping exploratory wells, and sampling groundwater and soil. Six exploratory wells were excavated in a triangular arrangement in high-risk areas near tanks, flares, and other sensitive points. Sampling was conducted with strict adherence to chemical alteration control principles, focusing on analyzing hydrocarbon and VOC concentrations. The results revealed that benzene concentrations in certain soil samples, including sample S10, exceeded the standard limits for groundwater protection. Additionally, BTEX and PAH compounds were detected in some samples, primarily attributed to atmospheric washout effects and pollutant emissions from industrial flares. VOC monitoring in exploratory wells using portable devices indicated significant levels of these compounds across all samples. Groundwater sample analysis showed hydrocarbon contamination only in one well downstream of the petrochemical site. Field data and analyses demonstrated that seasonal rainfall and atmospheric washout contribute to reducing pollutant concentrations in soil and their transfer to deeper layers. These findings highlight the importance of continuous monitoring of VOCs and hydrocarbons in industrial areas and underscore the role of seasonal rainfall and specific climatic patterns in mitigating contamination.
Keywords
Soil contamination
VOCs
Groundwater
Atmospheric washout
Assaluyeh Petrochemical company
Subjects
Al-Suwaiyan, M.S., Bashir, K., Aiban, S.A., Ishaq, A.M., 2002. Analytical model to quantify crude oil spill volume in sandy layered aquifers. Journal of Environmental Engineering 128(4), 320-326.
https://doi.org/10.1061/(ASCE)0733-9372(2002)128:4(320)
Chen, K. F., Kao, C. M., Chen, C.W., Surampalli, R.Y., Lee, M.S., 2010. Control of Petroleum-Hydrocarbon Contaminated Groundwater by Intrinsic and Enhanced Bioremediation. Journal of Environmental Sciences 22(6), 864–871.https://doi.org/10.1016/S1001-0742(09)60190-X.
Du, M., Li, M., Liu, W., Shi, M., Li, X., Xing, X., Qi, S., 2025. Field and Laboratory Study on the Distribution, Fate, and Transport of Polycyclic Aromatic Hydrocarbons in the Loess Porous Medium at a Refinery Polluted Site: Understanding the Soil–Groundwater Interface. Organic Geochemistry 200, 104902. https://doi.org/10.1016/j.orggeochem.2024.104902.
Dickhut, R.M., Gustafson, K.E., 1995. Atmospheric Washout of Polycyclic Aromatic Hydrocarbons in the Southern Chesapeake Bay Region. Environmental Science & Technology 29(6), 1518–1525. https://doi.org/10.1021/es00006a013.
Esmaeili, M., Nikpour, Y., 2015. Investigation and measurement of PCB, PAH, and heavy metal compounds in the waters of the Persian Gulf in the Assaluyeh and Bandar Abbas region. M.Sc. Thesis, Department of Marine Chemistry, Faculty of Marine and Oceanic Sciences, Khorramshahr University of Marine Science and Technology.
Gupta, A., Jha, A.K., Singh, A.K., Rajput, P., Gupta, T., 2020. Distribution of BTEX in Soils of an Urban Area: Kanpur Region, India. Journal of Energy and Environmental Sustainability 9, 61-66. DOI: 10.47469/JEES.2020.v09.100099
Gupta, P.K., Goel, M., Gupta, S.K., Bhargava, R.N., 2022. Fate, transport, and bioremediation of PAHs in experimental domain: An overview of current status and future prospects. Advances in remediation techniques for polluted soils and groundwater, 125-139. https://doi.org/10.1016/B978-0-12-823830-1.00017-1.
Jamali Dizaji, M., 2022. Numerical modeling of groundwater flow and pollutant transport in the Assaluyeh aquifer. M.Sc. Thesis, Department of Geology, Faculty of Earth Sciences, University of Tehran.
Japan International Cooperation Agency (JICA). 2014. The project for strengthening environmental management in petroleum industry in Persian Gulf and its coastal area. Islamic Republic of Iran, Ministry of Petroleum, Health, Safety and Environmental Department.
Khalefah, A.R.M., Omran, I.I., Al-Waily, M.J.,2024. Environmental Impact of Petroleum Refinery Effluent on Groundwater Pollution: A Case Study of Maysan Refinery, Iraq. Salud, Ciencia y Tecnología-Serie de Conferencias 3, 844-844.
Khodaei, K., Tabani, H., Shahsavari, A., Ghorashi, S., Boslik, Z., Rezazadeh, B., Mokhtari, M., 2021. Separation of petroleum pollution halos in groundwater in the industrial area of southern Tehran.
Lerner, D.N., Kueper, B.H., Wealthall, G.P., Smith, J. W.N., Leharne, S.A., 2003. An illustrated handbook of DNAPL transport and fate in the subsurface.
Li, Y., Duan, X.,2024. Wet deposition of polycyclic aromatic hydrocarbons in a remote area of Central South China from 2014 to 2017. Atmospheric Science Letters 25(3), e1201. https://doi.org/10.1002/asl.1201
Monfared Estahbanati, M., Hasanlu, M., Rousta, H., 2016. Investigation of air pollution and identification of suitable areas for vegetation expansion using spatial data (Case study: Assaluyeh County). National Geomatics Conference.
Nambi, I.M., Rajasekhar, B., Loganathan, V., RaviKrishna, R., 2017. An assessment of subsurface contamination of an urban coastal aquifer due to oil spill. Environmental monitoring and assessment 189, 1-17. https://doi.org/10.1007/s10661-017-5833-6.
Nasiri, S., Vaezihir, A., Ahmadishali, J., 2023. Designing soil contamination monitoring network in petroleum refineries by XGBoost weighting and geostatistical facility allocation methods. Environmental Science and Pollution Research 30(56), 118377-118395. https://doi.org/10.1007/s11356-023-30452-5.
Nasrabadi, T., Ruegner, H., Schwientek, M., Ghadiri, A., Hashemi, S.H., Grathwohl, P., 2022. Dilution of PAHs loadings of particulate matter in air, dust and rivers in urban areas: A comparative study (Tehran megacity, Iran and city of Tübingen, SW-Germany). Science of the Total Environment 806, 151268. https://doi.org/10.1016/j.scitotenv.2021.151268
Nayeb, F., 2024. Investigation of the Assaluyeh coastal aquifer in the Arya Sasol petrochemical zone and assessment of hydrocarbon contamination risk. M.Sc. Thesis, Department of Earth Sciences, University of Tabriz.
Pankow, J.F., Cherry, J.A., 1996. Dense chlorinated solvents and other DNAPLs in groundwater: History, behavior, and remediation 362. Portland, OR: Waterloo Press.
Ravindra, K., Thind, P. S., Mor, S., Singh, T., Mor, S.,2019. Evaluation of groundwater contamination in Chandigarh: Source identification and health risk assessment. Environmental Pollution 255, 113062. https://doi.org/10.1016/j.envpol.2019.113062.
Rhoades, C., Binkley, D.,1996. Factors influencing decline in soil pH in Hawaiian Eucalyptus and Albizia plantations. Forest Ecology and Management 80(1-3), 47-56. https://doi.org/10.1016/0378-1127(95)03646-6.
Rivett, M.O., Wealthall, G.P., Dearden, R.A., McAlary, T.A., 2011. Review of unsaturated-zone transport and attenuation of volatile organic compound (VOC) plumes leached from shallow source zones. Journal of Contaminant Hydrology 123(3-4), 130-156. https://doi.org/10.1016/j.jconhyd.2010.12.013.
Taghavi, A., Najafi, M., Etemad Saeid, N., Sedigh, M., 2017. Deformation history in the old Fars foreland, southeastern Zagros Fold-and-Thrust Belt. Journal of Earth Sciences 1.
Vaezi Hir, A., Mohammadzadeh, M.,2022. Identification of LNAPL petroleum pollutants in the Bandar Abbas refinery aquifer. Journal of Human and Environment, 59, Winter 2022.
Zhu, H., Chen, Y., Ruan, Z., Wang, H., Liu, D., Zhao, M., 2025. Comprehensive characterization of volatile organic compounds in Chinese chemical industry park soils: Spatial variation, source identification, and health risk assessment. Journal of Environmental Sciences 155, 48-59. DOI10.1016/j.jes.2024.06.035.
Zhang, P., Chen, Y.,2017. Polycyclic aromatic hydrocarbons contamination in surface soil of China: A review. Science of the Total Environment 605, 1011-1020. https://doi.org/10.1016/j.scitotenv.2017.06.247.
Advanced Applied Geology
Volume 15, Issue 2
Summer 2025
Pages 237-253