No erratic boulder with a diameter at any point of six feet or more may be moved from its location at the time of designation of a Special Natural Area District to another location within the Special District during development, enlargement or site alteration except in compliance with the provisions of this Section.

Prior to the moving of an erratic boulder from its present location to a location elsewhere within the Special Natural Area District, an application shall be filed with the City Planning Commission showing the present location and the proposed location. Moving of an erratic boulder will be permitted only by authorization of the Commission under the following circumstances:

(a)        where such a boulder is located in an area to be occupied by buildings, driveways, parking areas or recreation areas and it is not possible to avoid such location by minor adjustments in the arrangement of such buildings, driveways, parking areas or recreation areas on the site;

(b)        where the boulder's continued existence in its present location would create hazards or dangers; or

(c)        where authorizations granted by the Commission under the provisions of this Chapter require or clearly contemplate the boulder's relocation from its present position.

In issuing an authorization under this Section, the Commission shall require an appropriate relocation site, visible, if possible, from a public street, park, or public place, preferably on the zoning lot or elsewhere within the Special Natural Area District. The Commission may prescribe appropriate conditions to enhance the setting of the relocated boulder.