Final answer:
The Facilities Unit Leader would report to the Incident Commander if no Logistics Section Chief is assigned, maintaining a clear line of authority in the Incident Command System.
Step-by-step explanation:
If an individual is the Facilities Unit Leader and no Logistics Section Chief is assigned, the individual would report directly to the Incident Commander. The Incident Command System (ICS) is structured to provide a clear line of authority, even when certain positions are not filled. The Facilities Unit is part of the Logistics Section, so if there is no Logistics Section Chief, the next higher level in the command structure is the Incident Commander.