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3-4 materials generated by the clearing and grubbing operation will be disposed in the active portions of the landfill. The segregated soils will be used to construct final cover. Foundation Layer The one-foot foundation layer will be comprised of random onsite soils which constitute the in-place interim cover. The in-place material (approximately one foot), utilized as part of the foundation layer, will be scarified and compacted to the maximum density obtainable at optimum moisture using methods that are in accordance with accepted engineering standards. Prior to implementation of closure construction, an evaluation of the existing depth of cover will be conducted. Additional cover material will be placed over the existing cover at closure to achieve the desired foundation layer depth (minimum one foot) and grades for the final cover. In lieu of verification of the existence of the one-foot of existing interim cover, a total of a four-foot thick layer of select soil material will be placed to comprise foundation soil layer and the upper monolithic cover layer. This is the proposed approach to the Stage 1B Partial Final Closure Construction Project. Monolithic Soil Final Cover The proposed monolithic layer will be constructed with soils obtained from on-site borrow sources. Prior to placement, these materials will be moisture conditioned to approximately optimum moisture content and thoroughly mixed to obtain a near uniform condition. The material will then be placed in lifts with a maximum uncompacted thickness of six to eight inches. Each lift will be spread evenly and compacted to a minimum of 90 percent of the maximum dry density as determined by ASTM D1557. Where quality control tests indicate that the moisture content, density, saturated hydraulic conductivity, or grain size distribution of any lift, or portion thereof, does not meet the soil characteristics as specified in Appendix C (Construction Quality Assurance Plan), that particular portion shall be retested and, if necessary, reworked until the specified moisture, density, and saturated hydraulic conductivity have been attained. No additional material will be placed over an area until the previously placed material has been tested and found to meet the design specifications. Testing of the materials will be done in accordance with the CQA Plan included in Appendix C. Vegetation Moisture control through evaporation and/or transpiration of selected plants is the principal infiltration controlling mechanism in a monofill alternative final cover design. Vegetative cover plant species, if appropriate, will include native seasonal grasses and shrubs. The selected plant types will provide a good soil root distribution at varying, relatively shallow depths (up to approximately 24 inches) within the vegetative zone of the monofill cover section. All cover areas will receive the vegetative cover seed mix presented on Table 1 and depicted on the Erosion Control Plan (Figure 5). 3.2.3 Final Cover Transitions Final cover will be transitioned from the slope to the existing fill areas as shown on Figure 4 (Detail 7). The west toe of slope final cover transition is shown on Figure 6 (see Detail 6). The Stage 1A/1B slope final cover join is shown on Figure 6 (see Detail 5). Forward Landfill Stage 113 Partial Final Closure/Post-Closure Maintenance Plan-June 2011 SWT Engineering z:\projects\allied waste\forward\11-1014 partial fnl clsr pin\partial final closure plan document\text\sec 3.doc