8 C.F.R. § 234.4
International airports for the entry of aliens shall be those airports designated as such by the Commissioner. An application for designation of an airport as an international airport for the entry of aliens shall be made to the Commissioner and shall state whether the airport: (a) Has been approved by the Secretary of Commerce as a properly equipped airport, (b) has been designated by the Secretary of the Treasury as a port of entry for aircraft arriving in the United States from any place outside thereof and for the merchandise carried thereon, and (c) has been designated by the Secretary of Health, Education, and Welfare as a place for quarantine inspection. An airport shall not be so designated by the Commissioner without such prior approval and designation, and unless it appears to the satisfaction of the Commissioner that conditions render such designation necessary or advisable, and unless adequate facilities have been or will be provided at such airport without cost to the Federal Government for the proper inspection and disposition of aliens, including office space and such temporary detention quarters as may be found necessary. The designation of an airport as an international airport for the entry of aliens may be withdrawn whenever, in the judgment of the Commissioner, there appears just cause for such action.
8 C.F.R. §234.4