In those areas and portions of the city where the transmission or distribution facilities of all public utilities providing telephone service and those of all public utilities providing electric service are already placed or to be placed underground subject to the provisions set out in Section 5.12.300, the grantee shall likewise construct, operate and maintain all of its transmission and distribution facilities underground. For the purposes of this section, “underground” shall include a partial underground system, e.g., streamlining. Amplifiers in the grantee's transmission and distribution lines may be in appropriate housings upon the surface of the ground as reasonably approved by the public works supervisor of the city. The city shall not in any manner be responsible for any costs of liabilities incurred by the grantee in planning the grantee's facilities underground. (Ord. 93-03 §9 (part), 1993)