For all developments, enlargements or site alterations on Tier II sites, the following materials shall be submitted to the Department of Buildings. However, the submission requirements set forth herein shall not apply to an enlargement of an existing building, provided that such enlargement does not increase the lot coverage of said building. No building permit shall be issued until the Department of Buildings determines that the requirements of the Special Hillsides Preservation District have been met.

(a)        A survey map prepared by a licensed surveyor showing topography at two-foot contour intervals and indicating the existing slope of the land as it occurs in categories of 10–14 percent, 15–19 percent, 20–24 percent, 25 percent and greater; the location of existing buildings or other structures, patios, decks, swimming pools, walkways, driveways and private roads, including sidewalks and other impervious surfaces; and the location, caliper and species of all trees of six-inch caliper or more on the zoning lot and in the sidewalk area of the adjacent streets.

(b)        A site plan prepared by a registered architect or professional engineer indicating the location of all existing buildings or other structures; the location of all proposed buildings or other structures; the location of existing and proposed patios, decks, swimming pools, walkways, driveways and private roads, including sidewalks and other impervious surfaces; the location of all understory, including shrubs and ground cover; and the location, caliper and species of individual trees of six-inch caliper or more on the zoning lot and in the sidewalk area of the adjacent streets. The site plan shall identify those trees proposed to be removed and those trees proposed to be preserved, indicating for the latter the critical root zone, the location of any other area of no disturbance and the location of the staging area.

(c)        A grading plan that will show all existing and proposed contours at two-foot intervals, critical spot elevations, tops and bottoms of proposed slopes over 10 percent gradient and will indicate at least one longitudinal and one latitudinal cross-section showing both the original and proposed final ground surfaces, with grades, slopes and elevations noted.

(d)        An alignment and paving plan for any private road with a typical cross-section.

(e)        A landscaping and revegetation plan, prepared by a registered landscape architect, indicating the extent of vegetation and topsoil removal required for site preparation and development and the location and species of all new plantings.

(f)        A construction plan prepared by a registered landscape architect, registered architect, licensed surveyor or professional engineer showing the proposed location for the staging area, the proposed method for protecting trees, understory shrubs and ground cover during construction, as well as a description of the equipment to be employed in processing and disposing of soil and other material to be removed from the site. A tree protection plan for any tree proposed for preservation where the area of no disturbance is proposed to be modified.

(g)        An affidavit prepared by a registered landscape architect, registered architect, licensed surveyor or professional engineer stipulating the following:

(1)        prior to construction, no grading, filling, clearing or excavation of any kind shall be initiated until approval of a final grading plan by the Department of Buildings;

(2)        no construction equipment of any kind shall pass over areas to be preserved, according to the approved plans;

(3)        construction fences meeting the requirements of Section 119-217, paragraph (b), shall be erected around all vegetation proposed for retention; and

(4)        construction controls (erosion protection, drainage measures, etc.) shall be implemented according to the approved plan.

(h)        A drainage plan and soil report prepared by a professional engineer to protect natural features. The drainage plan shall describe the temporary (during construction) and permanent measures to collect, direct and discharge stormwater drainage from the site, indicating the direction of drainage flow and providing detailed plans and locations of all surface and subsurface drainage devices, walls, dams, sediment basins, stormwater storage (detention and retention) facilities, and other drainage facilities and protective devices. Such report shall include an estimate of runoff from the site after completion of any proposed development, enlargement or site alteration and provide a description with supporting information of the manner in which the proposed development, enlargement or site alteration complies with the requirements of Local Law 103 of 1989.