In case any portion of a planned community or planned unit development or a subdivision having lots not less than one-half acre in area is situated on land having an average slope of ten percent or more; the planning commission may recommend modification of the foregoing requirements of this title in a manner that will result in the best possible utilization of the land to be subdivided giving consideration to the topography and natural cover of the land and the general character of the proposed subdivision. The principles and standards in Sections 20.32.280 through 20.32.310 shall be observed. (Ord. 1046 NCS §1 (part), 1972; prior code §22.7.600.)