; acquisition of lands, and interests in lands; and preparation of lands for farming, and for construction of the Navajo Indian Irrigation Project pursuant to Public Law 87–483 ; $354,485,000, to remain available until expended: Provided , That such amounts as may be available for the construction of the Navajo Indian Irrigation Project may be transferred to the Bureau of Reclamation: Provided further , That not to exceed 6 percent of contract authority available to the Bureau of Indian Affairs from the Federal Highway Trust Fund may be used to cover the road program management costs of the Bureau: Provided further , That any funds provided for the Safety of Dams program pursuant to the Act of November 2, 1921 ( 25 U.S.C. 13 ), shall be made available on a nonreimbursable basis: Provided further , That for fiscal year 2019, in implementing new construction, replacement facilities construction, or facilities improvement and repair project grants in excess of $100,000 that are provided to grant schools under Public Law 100–297 , the Secretary of the Interior shall use the Administrative and Audit Requirements and Cost Principles for Assistance Programs contained in part 12 of title 43, Code of Federal Regulations, as the regulatory requirements: Provided further , That such grants shall not be subject to section 12.61 of title 43, Code of Federal Regulations