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The Module "I" slopes are approximately 4:1 and will, therefore, require a total of 2 -feet of soil compacted to a minimum 85 percent relative compaction. The shallow refuse areas generally have slopes flatter than 5:1. A minimum 3 -feet of soil compacted to a minimum 85 percent relative compaction will be placed in Module "I" locations where the slopes are flatter than 5:1.. A significant thickness of a relatively low permeability soil cover is currently in-place on the Module "I" slopes (Tables 2-1 and 2-2). The County is planning to have site personnel complete the placement of Partial Cover to achieve the required minimum thickness (Drawing C-1). In addition to the test pits currently excavated, site personnel will excavate additional potholes at approximately 300 -ft centers on slopes steeper than 5:1 and at 200 -ft centers on slopes flatter than 5:1. The thickness of the existing soil cover in these potholes will be verified and these results submitted to the County. Based on the test pit and survey results, a plan will be prepared detailing the thickness of additional soils to be placed throughout the Module "I" area. Prior to placement of the additional soil for Partial Cover, site personnel will perform a demonstration program on a section of the slope to assess the type of equipment required and the minimum number of passes needed to achieve the minimum relative compaction. The demonstration area will be approximately 100 feet by 100 feet and will be located in the vicinity of soil test pit S2 (Figure 2-1). Soil samples will be obtained from the demonstration area to develop compaction curves. Nuclear gage and moisture content testing will be performed following each pass of the compaction equipment to assess the minimum number of passes required. Once the placement and compaction procedure is established, site personnel will use this procedure to place the required additional Partial Cover soils. Following placement of the additional Partial Cover soils, each of the initial potholes will be surveyed to assess if the required cover thickness has been placed. In addition, random potholes will be excavated at approximately 500 -ft centers on slopes steeper than 5:1 and 200 -ft centers on slopes flatter than 5:1 to check that the minimum required thickness of soil cover is in place and that the relative compaction of the soils achieves the minimum relative compaction requirement. If the thickness or compaction do not achieve the required criteria, the failing areas will be delineated and reworked until the required criteria is achieved. The construction oversight and results of the test pit, survey, and demonstration programs will be summarized in a certification report. This report will be stamped by an Engineer registered in the 47717/SAC4R475 Page 7 of 19 Revised May 31, 2005 Copyright 2004 Kleinfelder, Inc. Partial Cover, Intermediate Cover and Drainage and Erosion Control Plan Foothill Sanitary Landfill