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(4) Slope Stability Factors of Safety. When required in this Title to provide site- <br /> specific geologic and engineering slope stability analysis, the following minimum <br /> slope stability factors of safety shall apply: <br /> A. A minimum factor of safety of 1.5 against static deep-seated failure. <br /> B. A minimum factor of safety of 1.5 against static surficial failure. <br /> C. A minimum factor of safety of 1.1 against seismic failure; <br /> (5) Temporary Cut Slopes at Setback Lines. Temporary cut slopes (i.e., for limited <br /> periods of time, slopes that are in the process of extraction prior to being <br /> backfilled) at setback lines shall not exceed one (1) foot horizontal to one (1) <br /> foot vertical, except that temporary cut slopes at setback lines to a maximum of <br /> one half (1/2) of a foot horizontal to one (1) foot vertical may be maintained if <br /> site-specific geologic and engineering analysis demonstrate through a slope <br /> stability analysis that the proposed temporary cut slopes will have a minimum <br /> slope stability factor of safety as required in Section 9-1415.3(k)(4). However, <br /> in the event that there are existing structures on the adjacent property (or the <br /> immediate potential for structures on the adjacent property), the excavation <br /> shall at not time be closer to the property line than a line projected on a slope of <br /> one (1) to one (1) from the property line to the toe of slope. <br /> (6) Final Slopes. Final cut and/or fill slopes shall not exceed two (2) feet horizontal <br /> to one (1) foot vertical, except as specified below: <br /> A. Final slopes to a maximum of one and one-half(1 1/2) feet horizontal to one <br /> (1) foot vertical may be maintained when site-specific geologic and <br /> engineering analysis demonstrate through a slope stability analysis that the <br /> proposed final slopes will have a minimum slope stability factor of safety as <br /> required in Section 9-1415.2(k)(4), while demonstrating suitability for the <br /> proposed end use and protecting against erosion (by means of revegetation <br /> or other methods approved by Development Services Division). <br /> B. Final slopes to a maximum of one (1) horizontal foot to one (1) foot vertical <br /> may be maintained under water (beginning five {5} feet below the lowest <br /> water table on the property experienced in the preceding three (3) years) <br /> when site-specific geologic and engineering analysis demonstrate through a <br /> slope stability analysis that the proposed saturated slopes will have a <br /> minimum slope stability factor of safety as required in Section 9- <br /> 1415.2(k)(4); <br /> (7) Fill Slopes. Fill slopes shall be constructed consistent with recommendations <br /> from a qualified civil/geotechnical engineer based upon site-specific geologic <br /> conditions, <br /> k. FENCING: Fencing four (4) feet in height consisting of not less than three (3) <br /> strands of barbed wire, or an approved equivalent, shall be placed around the <br /> excavation area where slopes steeper than two (2) feet horizontal to one (1) foot <br /> vertical are maintained. Six (6) foot high security fencing or an approved equivalent <br /> shall be required where slopes steeper than two (2) feet horizontal to one (1) foot <br /> vertical are created, if the proximity of such slopes to residential uses or other uses <br /> 4 <br />