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Draft Environmental Impact Report Page 14 P p g Forward Landfill Expansion Impact G.4: Increased erosion and sedimentation could occur, particularly during the construction phases of the landfill, due to grading and borrow soil excavation and transport operations. Soil disturbance and topographic alterations during planned staging of the landfill could occur in a period of increased soil erosion and sedimentation into the existing and later modified Littlejohns Creek. Preparation of the site would require up to 2.2 mcy of imported soil for operations over the life of the expansion and excavations of the borrow pit areas for soil cover, clearing of residual vegetation, and refuse cut-and-fill operations in order to create flat building pads and roadways and to provide the design drainage and runoff control. Erosion and sedimentation may also increase during the rainy season. The following procedures are proposed as part of the project: • The applicant's Joint Technical Document(2007) section 7 references an erosion control plan that delineates various actions to minimize erosion and sedimentation, including maintaining the effectiveness of the surface drainage control structures by keeping drainage ditches clear of debris and excessive vegetation and by making repairs, as necessary,to correct the effects of physical damage, erosion, settlement, or other events detrimental to effective operation of the drainage control system, and appropriate construction, landscaping, and maintenance of graded slopes and subsurface drainage systems. As part of that plan, grading operations would be scheduled to avoid the rainy season and be implemented by interim engineering control measures. Before grading is stopped, slopes would be directed to carry runoff to areas where erosion and sedimentation can be controlled. Truck beds would be hosed down to reduce soil spillage on paved roads and wind-blown dust. Relocation.of Littlejohns Creek could lessen the sedimentation potential to the creek. • Completed cells will be stabilized by the planting and maintenance of drought-resistant grasses. This will inhibit wind and water erosion and maximize the fertility of the soil in order to facilitate revegetation. • Temporary plantings, geofabric drapes, and erosion-preventing diversions of surface water will be constructed as appropriate on temporary slopes. • Regular operational and post-closure monitoring of erosion control structures and plantings will be done for a minimum of five years. Implementation of these procedures would reduce the impact to a less-than-significant level. Mitigation Measure G.4. None required.