105-42 - Authorizations to Alter Natural Features LAST AMENDED 2/2/2005 For a #development#, #enlargement# or #site alteration# located within the #Special Natural Area District#, the City Planning Commission may authorize: (a) modification of topographic features including existing natural topography and #topsoil# pursuant to Section 105-421 (Modification of topographic features on Tier I sites) and modification of #steep slopes# pursuant to Section 105-422 (Authorization of a development, enlargement or site alteration on a Tier II site or portion of a zoning lot having a steep slope or steep slope buffer); (b) modification of geologic features including the relocation of erratic boulders, and the alteration of rock outcrops pursuant to Sections 105-423 and 105-424; (c) modification of botanic environment, pursuant to Section 105-425; (d) alteration of aquatic features, pursuant to Section 105-426 in NA-1, NA-2 and NA-3 Districts. The Commission may prescribe appropriate additional conditions and safeguards to protect the character of the #Special Natural Area District#.