Laserfiche WebLink
4) Slope Stability Factors of Safety. When required in this Title to provide site-specific geologic and <br /> engineering slope stability analysis, the following minimum slope stability factors of safety shall <br /> 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 periods of time, <br /> slopes that are in the process of extraction prior to being backfilled) at setback lines shall not <br /> exceed one (1) foot horizontal to one (1) foot vertical, except that temporary cut slopes at <br /> setback lines to a maximum of one half (1/2) of a foot horizontal to one (1) foot vertical may be <br /> maintained if site-specific geologic and engineering analysis demonstrate through a slope <br /> stability analysis that the proposed temporary cut slopes will have a minimum slope stability <br /> factor of safety as required in Section 9-1415.3(k)(4). However, in the event that there are <br /> existing structures on the adjacent property (or the immediate potential for structures on the <br /> adjacent property), the excavation shall at not time be closer to the property line than a line <br /> projected on a slope of 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 to one (1) foot <br /> vertical for RMA 1 through 8, except as specified below: <br /> A. Final slopes to a maximum of one and one-half (1.5) feet horizontal to one (1) foot vertical <br /> may be maintained when site-specific geologic and engineering analysis demonstrate <br /> through a slope stability analysis that the proposed final slopes will have a minimum slope <br /> stability factor of safety as required in Section 9-1415.2(k)(4), while demonstrating suitability <br /> for the proposed end use and protecting against erosion (by means of revegetation or other <br /> methods approved by Development Services Division). <br /> 7) Fill Slopes. Fill slopes shall be constructed consistent with recommendations from a qualified <br /> civil/geotechnical engineer based upon site-specific geologic conditions. <br /> m. FENCING: Fencing four(4)feet in height consisting of not less than three(3) strands of barbed wire, <br /> or an approved equivalent, shall be placed around the excavation area where slopes steeper than <br /> two (2) feet horizontal to one (1) foot vertical are maintained. Six (6) foot high security fencing or an <br /> approved equivalent shall be required where slopes steeper than two (2) feet horizontal to one (1) <br /> foot vertical are created, if the proximity of such slopes to residential uses or other uses involving a <br /> concentration of people so warrants. (Development Title Section 9-1415.3[1]) <br /> n. SCREENING AND LANDSCAPING: Screening consistent with Chapter 9-1020 is required. <br /> (Development Title Section 9-1415.3[m]) <br /> 1) A Landscaping/Screening Plan shall be submitted to the Director for approval prior to the <br /> initiation of the approved excavation. The Plan may consist of Berms. The Berms may consist of <br /> overburden which may be removed upon reclamation of the mined areas. If berms are used for <br /> screening, they shall be between 6 and 8 feet in height and landscaped with natural grasses to <br /> provide erosion control and blend with surrounding flora. <br /> o. PONDING: All water utilized in the plant operation shall be disposed of behind a closed dike. <br /> (Development Title Section 9-1415.3[n]) <br />