The terminal areas within the meaning of 49 U.S.C. 13503 of any motor carrier of property or freight forwarder subject to 49 U.S.C. subtitle IV, part B, at any unincorporated community having a post office of the same name which is authorized to be served by such motor carrier of property or motor carrier of passengers in the transportation of express or freight forwarder, within which transportation by motor vehicle in the performance of transfer, collection, or delivery services may be performed by, or for, such motor carrier of property or freight forwarder without compliance with the provisions of 49 U.S.C. subtitle IV, part B, consists of:
(a) All points in the United States which are located within the limits of the operating authority of the motor carrier of property or freight forwarder involved, and within 3 miles of the post office at such authorized unincorporated point if it has a population less than 2,500, within 4 miles if it has a population of 2,500 but less than 25,000, or within 6 miles if it has a population of 25,000 or more;
(b) All of any municipality any part of which is included under paragraph (a) of this section; and
(c) Any municipality wholly surrounded by any municipality included under paragaph (b) of this section, or so wholly surrounded except for a water boundary. [32 FR 20049, Dec. 20, 1967, as amended at 41 FR 56655, Dec. 29, 1976; 51 FR 44297, Dec. 9, 1986; 62 FR 15423, Apr. 1, 1997]