A. 
In general. All developments shall be located so as to preserve the natural features of the site, to avoid areas of environmental sensitivity, to minimize the creation of impervious surface area, and to minimize negative impacts on the alteration of the natural environment.
B. 
Unbuildable area. The following natural features when present within a parcel constitute unbuildable area. No development, grading or filling, alteration of the natural character of the land, or construction of buildings, structures, or parking shall occur within these areas.
(1) 
Floodways, as defined in this chapter.
(2) 
Navigable waters, as defined in this chapter.
(3) 
Slopes of 20% or greater. Gradients between 20% and 30% may be used for construction if acceptable engineering solutions acceptable to a Professional Engineer and the Zoning Administrator.
(4) 
Wetlands, as defined in Part 500-2200.
C. 
Preservation areas. The following areas shall be preserved as undeveloped open space to the extent consistent with the reasonable utilization of land and in accordance with applicable federal, state, or local regulations:
(1) 
Vegetated areas. Significant trees or plant communities, including remnant stands of native trees or plant communities that are rare to the area or of particular landscape significance.
(2) 
Steep slope areas. Development on slopes of 12% and less than 20% shall be subject to the following conditions:
(a) 
The foundation and underlying material of any structure shall be adequate for the slope condition and soil type.
(b) 
The proposed development will not result in soil erosion, flooding, severe scarring, reduced water quality, inadequate drainage control, or other problems.
(c) 
The proposed development will not cause erosion or slope instability to neighboring property or cause structural damage to neighboring structures.
(d) 
The proposed development will preserve significant natural features by minimizing disturbance to existing topographical forms.
(e) 
The Village may require that a property be rezoned and developed as a Planned Unit Development District (PDD) to utilize flexible development standards to preserve steep slopes.
(3) 
Habitats of threatened or endangered wildlife as identified on federal or state lists, including, but not limited to, the federal Endangered Species Act and the Natural Heritage Inventory.
D. 
Mitigation. Where preservation is not consistent with the reasonable utilization of land, the Village may require mitigation through replacement of the resource or similar resource on the site, restoration of former natural amenities to the site, or other reasonable measures to protect or enhance the natural features of the land.