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P-� v berm, the landfill will be developed in modules beginning at the northwest corner and moving southerly over time. Excavated material will be used to develop screening berms at the north end of the property near Harney Lane and the site access road (Figure 3) . Onsite materials also will be used for cover. The maximum depth of excavation is expected to be to 72 feet above mean sea level (MSL) ; this is approximately 35 feet below the existing ground level in the northwestern corner of the site. Existing site elevations range from 105 feet MSL in the northwest to more than 120 feet MSL in the southeast. The final fill elevation is expected to be approximately 65 feet above the existing ground level (Figure 2) . As modules are completed, they will be brought to final grade and covered with a minimum of 4.5 feet of soil to provide infiltration protection and rooting zone for vegetation. The landfill surface will be fertilized and seeded with a moderately rooted, erosion -resistant vegetation native to the area. Irrigation of the vegetation is not proposed. Control Facilities Surface drainage from land upslope (east) of the site will be collected in perimeter ditches outside of the perimeter berm. The water will be con- veyed around the landfill and back into natural drainage channels. Onsite runoff will be directed via surface swales to a storm drainage sump and then pumped over the berm to the permanent perimeter ditch. The site design does not include installation of a leachate collection and removal system. Site geologic and hydrologic conditions and proposed drainage and cover specifications indicate that the operation should not generate sufficient leachate to impair beneficial uses of surrounding surface water or groundwater. Onsite gas generation and migration to surrounding areas will be moni- tored with probes along the landfill perimeter. An active gas extraction system will not be installed unless the probes find that significant offsite migration is occurring. The fine -textured soils in the area are expected to limit gas migration. A groundwater monitoring system will be developed around the landfill site in accordance with California Regional Water Quality Control Board re- quirements. Site Operations Refuse will arrive at the site via Harney Lane and the site access road that will extend south from Harney Lane. The entrance facility will be located about 900 feet south of Harney Lane and will control the waste stream entering the landfill. Load checking will be conducted from this location so that indiscriminate disposal of prohibited wastes can be min- imized. Accepted loads will proceed to the active landfill module, where refuse will be spread and compacted in lifts averaging 10 feet thick. The active 3