Do We Understand the Volatility of Petroleum Tank Farms? By Julie Peller, Ph.D.

Green Junction

When you drive the major highways in northwest Indiana, you observe the large petroleum tank farms where oil is stored. Nearby, Tanco Terminals is expanding its tank farm, which stores petroleum and food-grade oils, at the Ports of Indiana-Burns Harbor. People live near these tank farms and deal with the fumes and leaks from the tanks. According to the Energy Information Administration, more than 2 billion gallons of asphalt or residual fuel are stored in bulk storage tanks around the United States. 

The gases released from petroleum and petroleum-based products are mostly volatile organic compounds (VOCs). Many VOCs have strong odors, while others are less detectable by smell. Another community near lots of petroleum tanks is South Portland, Maine. According to the EPA, more than 12,600 people live within a mile of the tank farm known as the Citgo South Portland Terminal. 

The level of monitoring around most tank farms falls short of residents’ concerns and their exposure to pollution. For the Portland community, an outcome of a recent legal settlement is fenceline monitoring of certain VOCs. Residents were finally armed with information in 2025 about the chemical releases from the tanks and will continue to learn about pollution emissions near the industry.

Modern-day living depends on petroleum and other oil resources. While we mostly think of oil as a major fuel, it is a complex mix of chemicals (petrochemicals) used to make thousands of products. These include pharmaceuticals, fertilizers, plastics, personal care products, and many other synthetic materials. As long as we continue our consumptive habits, there will be a need for mining and storage of these chemicals, as well as for monitoring the pollution they release. Movements toward natural products are a way to lessen dependence on petroleum and improve the environment for thousands of people.

Julie Peller, Ph.D., is an environmental chemist (Professor of Chemistry at Valparaiso University). She has been writing a weekly column, The Green Junction, for the past seven years and is helping to move the call of Laudato Si to action. Her research interests include advanced oxidation for aqueous solutions, water quality analyses, emerging contaminants, air quality analyses, challenges along the Lake Michigan shoreline (such as Cladophora, water, and sediment contaminants), and student and citizen participation in environmental work.