(a) Tribes must either:

(1) Use the approved standards referred to in §170.454; or

(2) Request approval for any other road and highway bridge construction standards that are consistent with or exceed the standards referred to in §170.454.

(b) For designing and building eligible intermodal projects funded by the TTP, Tribes must use either:

(1) Nationally recognized standards for comparable projects; or

(2) Tribally adopted standards that meet or exceed nationally recognized standards for comparable projects.