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Mitigation Measure 4.2-2a (Alternatives 1, 2, and 3) The maximum steepness of the proposed excavation slopes shall be reduced to meet the County requirements for slope steepness and factor of safety. If slopes steeper than 1:1 are proposed for the reduced slopes, the proponent shall submit a site- specific geologic and engineering analysis that demonstrates (through slope stability analysis) that the revised slope design will have a minimum factor of safety of 1.5 under static conditions and 1.1 under seismic failure. � I Mitigation Measure 4.2-2b (Altematives 1, 2, and 3) If strong seismic shaking is experienced at the project site as the result of a moderate to large earthquake (M 6 or greater) along the CRSBBZ, then the project site shall be inspected by a qualified licensed civil or geotechnical engineer to determine if liquefaction or seismic subsidence has occurred and resulted in visible damage to j reclaimed lands. A report, including recommendations to repair any damage that E may have occurred, shall be submitted to the Development Services Division for review and approval. Upon approval by the Development Services Division, the proponent shall implement the recommendations set forth in the report. Mitigation Measure 4.2-2c (Alternatives 1, 2, and 3) Pursuant to Section 9-1415.2(k)(3) of the Development Title, if an approved slope does not remain stable, and an inspection confirms this condition, the Review Authority shall have the authority to seduce the slope or require other appropriate measures to correct any deteriorated slope. The operator of the site shall be responsible for the cost of such corrective actions. Level of Significance after Mitigation: Implementation of Mitigation Measures 4.2-2a through 4.2-2c would reduce the potential impacts of damage to reclaimed lands caused by earthquakes to a less- than-significant level. All uar Excavation Alternatives 1 2 and 3 Impact 4.2-3 Erosion of Post-Reclamation Slopes The reclamation plan proposes revegetating original reclamation slopes with a combination - of ground covet, including blando brom, rose clover, and annual ryegrass. In order to provide protection of slopes against erosion, the vegetative cover should have dense cover and fibrous roots. The proposed species, if providing continuous soil coverage, could provide the necessary erosion protection. However, the steepness of the proposed reclaimed slopes (1.5:1) could affect the effectiveness of this type of vegetative cover for erosion control. Soil erosion on slopes steeper than 3:1 can present problems for Draft Environmental Impact Report 4-18 ER-96-3