(a) An agreement shall be executed by and between the landowner or a legally authorized occupant or user of individually owned land and the applicant before any work by the applicant may be undertaken to construct a service line across such land. Such a service line shall be limited in the case of power lines to a voltage of 14.5 kv. or less except lines to serve irrigation pumps and commercial and industrial uses which shall be limited to a voltage not to exceed 34.5 kv. A service line shall be for the sole purpose of supplying the individual owner or authorized occupant or user of land, including schools and churches, with telephone, water, electric power, gas, and other utilities for use by such owner, occupant, or user of the land on the premises.
(b) A similar agreement to that required in paragraph (a) of this section shall be executed by the tribe or legally authorized occupant or user of tribal land and the applicant before any work by the applicant may be undertaken for the construction of a service line across tribal land. A service line shall be for the sole purpose of supplying an occupant or user of tribal land with any of the utilities specified in paragraph (a) of this section. No agreement under this paragraph shall be valid unless its execution shall have been duly authorized in advance of construction by the governing body of the Indian tribe whose land is affected, unless the contract under which the occupant or user of the land obtained his rights specifically authorizes such occupant or user to enter into service agreements for utilities without further tribal consent.
(c) In order to encourage the use of telephone, water, electric power, gas and other utilities and to facilitate the extension of these modern conveniences to sparsely settled Indian areas without undue costs the agreement referred to in paragraph (a) of this section shall only be required to include or have appended thereto, a plat or diagram showing with particularity the location, size, and extent of the line. When the plat or diagram is placed on a separate sheet it shall bear the signature of the parties. In case of tribal land, the agreement shall be accompanied by a certified copy of the tribal authorization when required.
(d) An executed copy of the agreement, together with a plat or diagram, and in the case of tribal land, an authenticated copy of the tribal authorization, when required, shall be filed with the Secretary within 30 days after the date of its execution. Failure to meet this requirement may result in the removal of improvements placed on the land at the expense of the party responsible for the placing of such improvements and subject such party to the payment of damages caused by his unauthorized act.