Which of the following products are commonly stored in UST systems?

UST systems, or Underground Storage Tanks, are primarily designed for storing certain types of liquids, particularly those that are regulated due to their potential environmental impact. Fuels and hazardous chemicals are the main products commonly stored in UST systems. This includes gasoline, diesel fuel, and various types of oils, as well as hazardous substances such as solvents and some industrial chemicals, which are required to be stored in a way that minimizes the risk of leaks and contamination.

USTs are regulated at both the federal and state levels because their contents can pose significant risks to soil and groundwater if a leak occurs. Therefore, the design, installation, and maintenance of these systems are subject to strict guidelines to ensure safety and environmental protection.

Other products such as food items, construction materials, or even just water are not typically stored in UST systems due to different storage requirements and safety considerations. For example, food items require specific temperature controls and storage environments, while construction materials generally do not involve liquid storage on this type of a broader scale. Water could be stored, but it is usually in a different type of containment system, primarily due to the regulatory environment surrounding drinking water and contamination risks.

This context greatly supports the understanding that fuels and hazardous chemicals are the primary and correct answer