(a)
Protection of existing rights
The Secretary of the Interior, if he shall find it to be in the public interest, is authorized to restore to tribal ownership the remaining surplus lands of any Indian reservation heretofore opened, or authorized to be opened, to sale, or any other form of disposal by Presidential proclamation, or by any of the public-land laws of the United States: Provided, however, That valid rights or claims of any persons to any lands so withdrawn existing on the date of the withdrawal shall not be affected by this Act: Provided further, That this section shall not apply to lands within any reclamation project heretofore authorized in any Indian reservation.