Few years back, we were hauling fill out to our local airport. Since the airport wasn't technically closed, we had to attend ground school. The instructor told us about the dangers of, and to jets.
After construction work, the runway itself is swept off, as well as a margin beside. Jets can suck small rocks into the blades and..........well..............
We also learned that if we were parking our equipment, we must remain a certain distance from the runway as the wash from a large plane can literally blow a vehicle over!