Normal house and jobsite debris is fine. The limits come from Georgia law and from what Gilmer County turns away.
Georgia bans yard trimmings from lined landfills statewide. Leaves, grass, brush, shrub and tree prunings and old Christmas trees have to be kept separate and composted or chipped. Land-clearing material like whole trees and stumps is treated differently under that rule, which is worth sorting out before a lot gets cleared.
Gilmer County goes further than the state. The county does not accept stumps, brush, yard trimmings, concrete or rock at its landfill at all. If your job makes a pile of broken concrete, block or stone, say so when you book so it can be routed somewhere that will take it.
Hazardous waste, liquids, paint, solvents, fuel and asbestos stay out of every container, and the county accepts no hazardous or infectious medical waste. Tires, appliances and electronics should be kept separate and mentioned up front.
One more local rule: the city does not allow waste from outside the city limits to be dropped into a container sitting inside them. If you are hauling from a second property, tell your account manager so the right container goes to the right address.