Most of the diesel fuel consumed in the United States is produced in U.S. refineries
U.S. refineries produce most of the diesel fuel that the United States consumes. In 2016, imports of ultra-low sulfur distillate (ULSD) fuel oil (distillate fuel with a sulfur content of 15 parts per million or less and sold as diesel fuel and heating oil in the United States) were equivalent to about 2% of total U.S. ULSD consumption. About 73% of those imports were from Canada.
How does diesel fuel get to a refueling station?
Most diesel fuel moves by pipeline from refineries and ports to terminals near major consuming areas. Barges and trains also move diesel fuel to terminals. Trucks transport the diesel fuel from the terminals to retail service stations and to large volume consumers such as vehicle fleet operators.
Diesel fuel and other products are sent through shared pipelines in batches. These batches are not physically separated in pipelines, and some mixing or commingling of products may occur. Because mixing is possible, the quality of the diesel fuel and other products must be tested to make sure they meet required specifications as they enter and leave pipelines. When products fail to meet local, state, or federal specifications, they are either removed and trucked back to a refinery for further processing, or they are sold as different products.