Existing natural features, such as trees, brooks, drainage channels and views shall be retained. Whenever such features interfere with the proposed use of property, the retention of the maximum amount of such features consistent with the use of the property shall be required.

The design of development shall be arranged to conserve environmentally sensitive features by locating buildings and structures within the improvable area of the site, subject to the preemption by the New Jersey Freshwater Wetlands Protection Act with respect to general or individual permits issued by the New Jersey Department of Environmental Protection. An applicant may be required to submit alternative designs to demonstrate that such features have been conserved to the maximum practical extent.

Design shall be arranged with particular attention to conserve the following features:

Maintain or improve groundwater quality and recharge particularly to the Englishtown formation and to the Mount Laurel and Wenonah formations.

Not exceed the capacity of water supply resources.

Maximize the use of natural systems to protect surface and groundwater supplies.

Prevent the discharge of pollutants that may contaminate or degrade surface water supplies, particularly in Category One watersheds (Weamaconk Creek and McGellairds Brook) and watersheds of public water supply (Manalapan Brook and Matchaponix Brook).

Maintain wildlife corridors.

Minimize disturbance of steep slope areas. Construction on steep slopes shall be avoided wherever possible. However, appropriate building designs and limited disturbance on steep slopes may be permitted, provided that within any development or tract, construction including buildings, streets, parking, grading, excavation and fill, or stripping of vegetation on steep slopes of 10% or more shall be restricted in the following way:

Maintain stream corridors. Unless a more restrictive federal, state or local standard applies, disturbance of stream corridors shall be regulated pursuant to § 95-8.12 of this chapter.

Authority to require revisions. The municipal agency responsible for plan approval (Planning Board or Board of Adjustment) may, on the basis of environmental impact, require revisions to design or layout.

All proposed grading shall preserve the salient natural features of the land being developed.

Proposed grades shall not alter the natural contour of the land by more than three feet unless the conditions identified in § 95-8.3C(7) are met and/or the area being graded is to be used for management of stormwater runoff, consistent with best management practices as defined by the New Jersey Department of Environmental Protection, and as supplemented by the Development Regulations of the Township of Manalapan.

Proposed grading activities shall not propose excavation on slopes greater than 15%.

Proposed grading activities shall not require foundations for any structure to be exposed by more than four feet on the front, rear and side elevations of the structure. Grading may permit the full exposure of the rear foundation wall so as to permit the construction of walk-out basements. However, walk-out basements and the related grading shall only be permitted when the natural contour of the land, measured 10 feet from the foundation, slopes away from the foundation at a minimum of 2%.

On any lot that is less than 80,000 square feet in area, cellars and basements are permitted only where the depth from the original grade to the seasonal high groundwater table is greater than six feet.

The seasonal high groundwater table elevation shall be certified by a New Jersey licensed professional engineer. The New Jersey licensed professional engineer or his/her representative shall determine the seasonal high groundwater table elevation through the use of a test pit excavation. If a test pit excavation cannot be performed due to site conditions, a soil boring may be permitted only at the discretion of the Township Engineer. The Township Engineer shall witness all test pit excavations or soil borings performed to determine the seasonal high groundwater table with respect to the construction of building basements or cellars or stormwater management facilities. The seasonal high groundwater table shall be the highest observed elevation of soil mottling or groundwater seepage within the test pit excavation or soil boring. If both occur, the higher elevation shall be considered the seasonal high groundwater table for design purposes. One test pit excavation or soil boring shall be performed for each proposed basement or cellar within a development project. Fewer test pits or soil borings may be permitted at the discretion of the Township Engineer. The test pit or soil boring shall be a maximum of 25 feet from the footprint of the proposed basement or cellar. The quantity and location of the test pit excavations or soil borings for the purposes of determining the seasonal high groundwater table with respect to stormwater management facilities shall be approved by the Township Engineer.

The import of fill material, and grading activities to mound, terrace, or otherwise alter the original lot grade by more than three feet to meet the requirements of § 95-7.34B for the required elevation above the groundwater to the lowest floor elevation of the principal building, are prohibited unless: