25 C.F.R. § 169.112
(b) We may approve a right-of-way over or across individually owned Indian land that provides for nominal compensation, or compensation less than a fair market value, if:
(3) The individual Indian landowners execute a written waiver of the right to receive fair market value and we determine it is in the individual Indian landowners' best interest, based on factors including, but not limited to:
(c) We will require a valuation to determine fair market value, unless:
(d) The grant must provide that the non-consenting individual Indian landowners, and those on whose behalf we have consented under § 169.108(c), or granted the right-of-way without consent under § 169.107(b), receive fair market value, as determined by a valuation, unless: