A. After August 28, 1969, extensions of telephone distribution lines on applicants' owned and leased properties, and in industrial parks, necessary to furnish permanent telephone service to new commercial and industrial buildings and to new multiple-occupancy buildings, shall be made underground.
B. The application of these regulations is not mandatory for extensions of lines to provide telephone service to customers whose premises are so unesthetic that the construction of underground lines would serve no purpose. Customers of this nature might include gravel pits and other mining operations, junk yards, railroad yards, and steel mills.