(a) We may disapprove a request for an amendment of a right-of-way only if at least one of the following is true:

(1) The Indian landowners have not consented to the amendment under §169.107 and we have not consented on their behalf under §169.108;

(2) The grantee's sureties for the bonds or alternative securities have not consented;

(3) The grantee is in violation of the right-of-way grant;

(4) The requirements of this subpart have not been met; or

(5) We find a compelling reason to withhold approval in order to protect the best interests of the Indian landowners.

(b) We will defer, to the maximum extent possible, to the Indian landowners' determination that the amendment is in their best interest.

(c) We may not unreasonably withhold approval of an amendment.