Buffer Area. Developments shall have a minimum buffer area established around the entire perimeter of the property of 35 feet; provided, however, that when the maximum natural ground surface slope, perpendicular to and within 100 feet of the perimeter, at any point on the perimeter is greater than 10%, the width of the buffer area shall be increased by one foot for each 1% increase in grade in excess of 10%; and, provided further, in the case of small or irregular properties, where the minimum buffer area prescribed as aforesaid would create a special hardship the Board of Commissioners, after receiving the recommendation of the Planning Commission, may reduce such minimum buffer area or eliminate it in its entirety, in its sole discretion. The buffer area shall be preserved in its natural state; provided, however, that additional planting and screening may be required. Vehicular and pedestrian access to the development through the buffer area shall be so constructed as to minimally disturb said buffer area.