Ga. Code § 40-1-126
In circumstances where a motor carrier is engaged in both interstate and intrastate commerce, it shall nevertheless be subject to all the provisions of this part so far as it separately relates to commerce carried on exclusively in this state. It is not intended that the department shall have the power of regulating the interstate commerce of such motor carrier, except to the extent expressly authorized by this part as to such commerce. The provisions of this part do not apply to purely interstate commerce nor to carriers exclusively engaged in interstate commerce. When a motor carrier is engaged in both intrastate and interstate commerce, it shall be subject to all the provisions of this part so far as they separately relate to commerce carried on in this state.
OCGA § 40-1-126