25 CFR 170.427 - How may an IRRTIP be amended?
(a) A tribe may amend the IRRTIP by changing its TTIP on or before July 15 and submitting the changed TTIP to BIA for inclusion in the IRRTIP. BIA's regional office will review all submitted information with the tribe and provide a written response (approving, denying, or requesting additional information) within 45 days. If the proposed IRRTIP amendment contains a project not listed on the current approved IRRTIP, BIA must submit the proposed amendment to FHWA for final approval.
(b) BIA may amend the IRRTIP:
(1) To add or delete projects or reflect significant changes in scope at any time if requested by the tribe; and
(2) To reduce funding or reschedule a project after consulting with the affected tribe and obtaining its consent, if practical.
(c) The Secretary may not reduce funding for or reschedule a project that is the subject of a negotiated agreement, except under the terms of the agreement.
(d) BIA amends the IRRTIP using the same public involvement process used to develop the original IRRTIP.