No land shall be used or structure erected where the land is held unsuitable for such use or structure by the Plan Commission by reason of flooding, concentrated runoff, inadequate drainage, adverse soil or rock formation, unfavorable topography, lower percolation rate or bearing strength, erosion susceptibility, or any other feature likely to be harmful to the health, safety, prosperity, aesthetics, and general welfare of this community. The Plan Commission, in applying the provisions of this section, shall in writing recite the particular facts upon which it bases its conclusion that the land is not suitable for certain uses. The applicant shall have an opportunity to present evidence contesting such unsuitability if he so desires. Thereafter, the Plan Commission may affirm, modify or withdraw its determination of unsuitability. All lots shall abut upon a public street, and each fan-shaped lot shall have a minimum street frontage of 40 feet.