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0 The method of drainage of terraces for temporary slopes at set back lines shall be submitted to Development Services Division for I approval. The reclamation plan presents engineering drawings and specifications for a reclaimed slope drainage system which conform to the requirements of this standard. The plan includes bench drain catch basins on benches that are sloped into the fill at five percent. Each slope has at least one down-slope drain which is connected to the drainage basins. The maximum spacing of down-slope drainage pipes (at the base of the reclaimed slopes) would be 1,500 feet. i Sec. 9-1415.3(k) (3) Slope Modification Requirement. The Review Authority may require slopes flatter than those specified below for safety or aesthetic purposes if the proximity of residential and other urban uses, waterways or roads, the instability of materials, or the surrounding terrain so warrants. If after one.(1)year or more of extraction the approved slope does not remain stable, the Review Authority shall have the authority to reduce the slope or require other appropriate measures in the immediate area and other areas as deemed necessary in order to correct the condition as well as require the operator to correct the deteriorated slope. The reclamation plan does not specifically acknowledge this standard. However, the proposed project would be required to comply with the standard in the event of the deterioration of slopes at the project site (refer to Mitigation Measure 4.2-2c). It is possible that ineffective revegetation or slope failures could result in required reduction in the steepness of proposed slopes Sec. 9-1415.3(k)(4) Slope Stability Factors of Safety. When required in this Title to provide site-specific geologic and engineering slope stability analysis, the following minimum slope stability factors of safety shall apply: (A) A minimum factor of safety of 1.5 against static deep seated failure. (B) A minimum factor of safety of 1.5 against static surficial failure. (C) A minimum factor of safety of 1.1 against seismic failure. i The slope stability analyses prepared for the project (Kleinfelder, 1997) evaluated the potential for failure of the excavation and reclaimed slopes under static and pseudo-static (seismic) conditions. The results of the analysis indicate that the minimum factors of safety required by the standard would be met for the final slopes. Draft Environmental Impact Report 6 ER-96-3