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1* r Closure 2.1 Limits of Waste and Final Cover Topography The final closure configuration for the Foothill Sanitary Landfill (FSL) allows final elevations to the presently -permitted limit of 432 ft. MSL. Refuse will be placed within 200 feet of the property boundary, except in the southeastern portion of the project, where the County tentatively plans to retain the existing pond (JTD Figure 6). At completion, the limits of waste will include approximately 674 acres (which excludes the pond area), entirely within the 800 acre parcel (JTD Figure 2). The sequence of fill, and the extent of each module, will be selected by the County. However, the County reserves the option to place refuse on 750 acres, including the pond area, subject to fulfilling all CEQA and related regulatory requirements. The final grading contours are shown on Figure B-1. 2.2 Closure Phasing Section 21090(b)(1)(D) of Title 27, California Code of Regulations (Prompt Incremental Closure), states, in -part, that "To the extent feasible, based on site-specific factors, the complete closure including final grading and installation of the final cover, for each portion of the landfill shall be implemented as soon as possible after that portion reaches final elevation". San Joaquin County will comply with this requirement as portions of the landfill reach final elevations. The upper portion of Module "I" has reached final elevation, and has received an ET final cover in 2006 (JTD Figure2). This area may be accepted as "closed" by the Regional Water Quality Control Board based on the data collected at the test area in the next four years. The County intends to close the remainder of the landfill also using an ET cover, similar to that now in place on the Top Deck area of Module "I". Based on performance modeling, the ET cover will be approximately 4.5 feet thick, constructed with onsite soils. Future closure phases will be considered when a portion of the landfill is available for closure that includes a reasonable portion of the pennanent closed surface to the edge of the landfill. At this time, additional closure of landfill surfaces is not contemplated for at least 15 years. 2,3 Site Life and Volumetric Calculations The capacity of the landfill is anticipated to be fully utilized in 2082 (JTD Table 5). This estimate does not include the effect of settlement and consolidation, which is highly variable, and is dependent upon such factors as type of waste, climate, and fill operations. Foothill Sanitary Landfill b -S Public Works/Solid Waste Preliminary CPCM Plan County of San Joaquin — Rev July 2010