About Storage Tanks
Storage tanks are big containers, often cylindrical in shape, that are designed to hold large quantities of liquids or gases. They often have piping and pump stations to move the contents. Depending on the intended use, they can be located underground or aboveground.
Underground Storage Tanks
About 95 percent of all underground storage tanks (USTs) store petroleum products like gasoline or oil. They are located underground to lessen the risk of explosion. USTs may also hold industrial chemicals, pesticides, or even food products. The most common place to find a UST is at a gas station, where the majority of tanks contain gasoline and fewer than 10 percent contain diesel fuel. Similarly, airports and truck fleet refueling facilities have USTs for jet fuel and hydraulic fluid in addition to gasoline and diesel fuel. Most dry cleaners use hazardous chemicals to clean clothes, and the most commonly used chemical (perchloroethylene) is often stored in USTs. Automotive service stations and oil change businesses frequently collect used oil in aboveground storage tanks (ASTs) or USTs before proper disposal or recycling. Even residences may have USTs, since heating oil was used to produce heat before natural gas was widely available.
Aboveground Storage Tanks
Aboveground storage tanks are situated aboveground, partially buried, bunkered, or in a subterranean vault. Their design depends on the type of material being contained, and storage conditions such as temperature, pressure, and storage time. ASTs provide a significant storage function for many industries in Indiana. Farmers use them to store the liquid fertilizer and bulk substances that they depend on to grow crops. ASTs also are used to store petroleum products—such as motor fuels, solvents, heating oil, lubricants, and used oil—that are typically found in fuel marketing terminals, refineries, and fuel distribution centers. They are commonly located in airports, school bus barns, hospitals, automotive repair shops, oil change businesses, military bases, and industrial plants.