25 CFR 170.456 - When can a tribe request an exception from the design standards?
A tribe can request an exception from the design standards in Appendix B of this subpart under the conditions in this section. The tribe must submit its request for a design exception to the BIA Regional Office for approval. If the BIA Regional Office has design exception approval authority within their IRR Stewardship Plan with FHWA, they may approve or decline the request; otherwise BIA forwards the request to FHWA. The engineer of record must submit written documentation with appropriate supporting data, sketches, details, and justification based on engineering analysis.
(a) FHWA or BIA may grant exceptions for:
(1) Experimental features on projects; and
(2) Projects where conditions warrant that exceptions be made.
(b) FHWA or BIA can approve a project design that does not conform to the minimum criteria only after giving due consideration to all project conditions, such as:
(1) Maximum service and safety benefits for the dollar invested;
(2) Compatibility with adjacent features; and
(3) Probable time before reconstruction of the project due to changed conditions or transportation demands.
(c) FHWA or BIA have 30 days from receiving the request to approve or decline the exception.