The loading minimum is the amount of grain that must be consolidated at an elevator before a train can pick-up and transport the grain. Railroads typically incentivize terminal elevators to load shuttle trains as quickly as possible. For example, BNSF provides rate discounts if elevators load railcars in under 15 h (Burlington Northern Santa Fe, 2015). A value of 13 h is used because, according to conversations with 3–4 terminal elevator operators in North Dakota, grain shuttle loading elevators typically load grain shuttle trains in significantly less than 15 h. In contrast, multi-car (6–30 railcars) trains are typically loaded in one day (Tolliver and Bitzan, 2002).