N.C. Gen. Stat. § 136-140.1

(1) Notwithstanding any other provision of this Article, the Department of Transportation may permit individuals or groups participating in its Adopt-A-Highway Program access to controlled access facilities for the purpose of removing litter from the right-of-way. Acknowledgment of participation in the program may be indicated by appropriate signs that shall be owned, controlled, and erected by the Department of Transportation. The size, style, specifications, and content of the signs shall be determined in the sole discretion of the Department of Transportation. The Department of Transportation may issue rules and policies necessary to administer the program.

(2) Adopt-A-Highway participants may use contract services to clean the roadside of the sections of highway the participants have adopted only in accordance with the rules and policies issued by the Department of Transportation.