by the 115th Congress of the United States, Public Law 115-91 — Division B
“ The fair market value of the land to be obtained by the Secretary concerned under subsection (a) in exchange for the conveyance of real property by the Secretary under such subsection shall be at least equal to the fair market value of the conveyed real property, as determined by the Secretary. If the fair market value of the land is less than the fair market value of the real property to be conveyed, the recipient of the property shall pay to the United States an amount equal to the difference in the fair market values. ”
