Notwithstanding any other provision of law, the Commissioner is authorized to dispose of by warranty deed, or otherwise, any land acquired by him on behalf of the United States, or obtained by the United States pursuant to treaty between the United States and Mexico, and not required for project purposes, under procedures to be formulated by the Commissioner, to adjoining landowners at such price as he considers fair and equitable, and, if not so disposed of, to turn such land over to the General Services Administration for disposal under the provisions of chapters 1 to 11 of title 40 and division C (except sections 3302, 3307(e), 3501(b), 3509, 3906, 4710, and 4711) of subtitle I of title 41.