right off the Georgia DMV website:
What are the highway user impact fees?
O.C.G.A. § 40-2-151.1 provides for annual highway user impact fees that apply to certain heavy vehicles. The heavy vehicle highway user impact fee is $50.00 for any vehicle with a gross vehicle weight rating of 15,500 lbs. to 26,000 lbs. For vehicles with a gross vehicle weight of 26,001 lbs. or higher, the heavy vehicle highway user impact fee is $100.00. The highway user impact fees does not apply to vehicles used as part of interstate commerce, i.e., those vehicles registered in the International Registration Plan (“IRP”).