Before that portion of any nonconforming structure which exceeds the height limitation established by the airport approach zoning map and Section 17.45.020 may be structurally altered and before any nonconforming structure or tree may be replaced, reconstructed, allowed to grow higher or replanted, a permit must be secured from the planning director authorizing such structural alteration, replacement, reconstruction or change. These portions of an existing nonconforming structure below the applicable height limitations may be structurally altered, repaired and added to, and those portions of an existing nonconforming structure above the applicable height limitation may be repaired and minor replacements made therein without securing such a permit unless such structural alteration, repair, addition, or enlargement exceeds the applicable height limitation. No such permit shall be granted that would allow the creation of an airport hazard or permit a nonconforming structure or tree or nonconforming use to be made or become higher or become a greater hazard to air navigation than it was on the date that this chapter was made applicable to a particular airport. All other applications for such permits may be granted. (Ord. 5020 § 19, 2020; Ord. 2719 § 1, 1982)