All proposals to grade, fill, or excavate land or to erect a structure for human habitation (sometimes referred to herein as the "proposal") shall be referred to the city engineer who shall make a preliminary determination by reference to the maps and materials maintained in the city engineer's office if any of the unsafe physical conditions described in section 10-18-2 of this chapter appear to exist in relation to the real property which is included in the proposal. (Ord. 2013-04, 4-18-2013, eff. 4-19-2013)