Final rule is available here.
Here is the Summary:
This final rule updates the Tribal Transportation Program regulations (formerly the Indian Reservation Roads Program) to comply with statutory updates. The Tribal Transportation Program is a program to address the surface transportation needs of Tribes. This rule reflects statutory changes in the delivery options for the program, clarifies the requirements for proposed roads and access roads to be added to, or remain in, the inventory, revises certain sections that were provided for informational purposes, and makes technical corrections.