(a) Future Uses. No material change shall be made in the use of land, and no structure or tree shall be erected, altered, planted, or otherwise established, in any airport approach zone, airport turning zone or airport transition zone, unless a building permit therefor shall have been applied for and granted. Each such application shall indicate the purpose for which the building permit is desired, with sufficient particularity to permit it to be determined whether the resulting use, structure, or tree would conform to the regulations herein prescribed. If such determination is in the affirmative, the building permit applied for shall be granted; provided, however, that the requirements of Title 29, chapters 3 and 5, Virgin Islands Code, are met.
(b) Existing Uses. Before any existing use, structure or tree may be replaced, substantially altered or repaired, rebuilt, allowed to grow higher, or replanted, within any airport approach zone, airport turning zone or airport transition zone, a building permit must be secured authorizing such replacement, change or repair. No such building permit shall be granted that would allow the establishment or creation of an airport hazard or permit a nonconforming use, structure, or tree to be made or become higher, or become a greater hazard to air navigation, than it was on July 1, 1957, or than it is when the application for a building permit is made. Except as indicated, all applications for a building permit for replacement, change or repair existing use, structure, or tree shall be granted; provided, however, that the requirements of Title 29, chapters 3 and 5, Virgin Islands Code, are met.