This research-in-progress paper is part of an ongoing investigation that explores the role of information and digital systems for understanding congestion challenges and management approaches in bulk cargo marine terminals and supply chains. This paper contributes to the broader investigation by developing a discrete-event simulation model to improve understanding of the impact of driver behaviors and scheduling parameters in the use of a digital terminal appointment system on truck flows in the supply chain and turnaround times at the terminal. The data supporting the simulation model was collected from an RFID-enabled weigh-bridge system of an Australian terminal operator and GPS units mounted on trucks. Simulation results indicate that even low levels of system use can reduce truck turnaround times and reduce service time uncertainty. Interestingly, the truck turnaround time benefits resulting from the use of the appointment system are particularly significant when the terminal operates at high capacity.