19 U.S.C. § 81l: Facilities to be provided and maintained

Adequate slips, docks, wharves, warehouses, loading and unloading and mooring facilities where the zone is adjacent to water; or, in the case of an inland zone, adequate loading, unloading, and warehouse facilities; Adequate transportation connections with the surrounding territory and with all parts of the United States, so arranged as to permit of proper guarding and inspection for the protection of the revenue; Adequate facilities for coal or other fuel and for light and power; Adequate water and sewer mains; Adequate quarters and facilities for the officers and employees of the United States, State, and municipality whose duties may require their presence within the zone; Adequate enclosures to segregate the zone from customs territory for protection of the revenue, together with suitable provisions for ingress and egress of persons, conveyances, vessels, and merchandise; Such other facilities as may be required by the Board.