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3-5 3.2.4 Sources of Cover Material Materials for construction of the final cover will be obtained from the on-site soil borrow area located directly north of the Stage 1A/113 Partial Final Closure areas. The CQA program for the final cover construction is included in Appendix C and summarized in Section 3.2.5. 3.2.5 Final Cover Construction Quality Assurance The construction of the final cover system shall be carried out in accordance with the CQA Plan included in Appendix C. The implementation of the CQA Plan will provide documentation that suitable materials and standard construction practices are used to place the final cover system and to document that placement is consistent with the closure plan design specifications in 27 CCR, Sections 20323 and 20324. Elements of the CQA Plan include: project description and definitions, qualifications and responsibilities, requirements for the final cover evaluation, inspection standards, testing frequencies, meetings, and documentation. This information will be collected during final closure construction and incorporated into the project's final closure construction CQA Report which will be submitted to the appropriate agencies for recording and reporting purposes. The design professional who prepares the CQA Plan shall be a registered civil engineer or certified engineering geologist. 3.3 Final Grading This section describes the proposed final grading contours for the Stage 1B Partial Final Closure area, which was designed to promote lateral run-off of surface water and minimize the effects of settlement. Perimeter maintenance and deck access roads are also designed to provide for maintenance of the final cover and environmental control systems throughout the post-closure maintenance period. The final grading plans (Figures 7, 8 and 9) present the landfill configuration after closure of Stage 1B. The final slopes of Stage 1B are designed at maximum grades of 3:1 (horizontal to vertical) or flatter with exception of the bench which is set at a maximum of a 50-foot interval with 2:1 slope as shown on Figure 4 (see Detail 2). The final grading configuration was designed by a registered civil engineer in accordance with 27 CCR, Section 21090 (b)(1)(C). In addition to prevent any future inundation of the landfill from the adjacent creek during peak storm events, a flood protection berm/perimeter road improvement is proposed. Soil will be placed and compacted along a portion of the toe of the west facing slope of the FL for the west toe of slope final cover transition (see Detail 6 on Figure 6). The objective of this engineered fill will be to build up the grade of the perimeter road to elevation above a 100- year flood event. Forward Landfill, Inc. will monitor this area for performance and any excess erosion during future storm events. 3.4 Landfill Settlement 3.4.1 Settlement Analysis Settlement analyses were completed to evaluate how the FL containment system will respond through time as refuse decomposes and is mechanically compressed. These analyses considered the consolidation potential of native sub grade soils as well as the settlement potential of both existing and future refuse materials. These analyses are 1101 included in Appendix D. 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