The utility shall construct, own, operate, and maintain an underground telephone distribution system only along public streets, roads, and highways which the utility has the legal right to occupy, and on public lands and private property across which rights-of-way and easements satisfactory to the utility may be obtained by the utility without cost or condemnation, in reasonable time to meet service requirements. Rights-of-way and easements shall be cleared of trees, tree stumps, and other obstructions at no charge to the utility, and shall be graded to within 6 inches of final grade by the applicant before the utility will commence construction. The clearance and grading shall be maintained by the applicant during construction by the utility. If, subsequent to construction, the clearance or grade is changed in such a way as to require relocation of the underground facilities, the cost of the relocation shall be borne by the applicant or his successor.