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3-3 specific to existing on-site materials that are available for final cover construction and vegetative conditions typical of the area near the landfill. The 2005 report is included as Appendix B. Based on the GLA alternative final cover report (Appendix B), it was determined that a four- foot thick monolithic alternative final cover section composed of on-site soils will satisfy the regulatory requirements for an alternative final cover as defined in 27 CCR. More specifically, the modeling completed as included in GLA's report indicates that the alternative final cover system constructed using available on-site soils would afford superior protection against water quality impairment. A traditional barrier layer is not proposed for the alternative final cover design. Site-specific conditions at the FL rendered a performance criteria based on annual surface water infiltration through the proposed alternative final cover. Therefore, the alternative final cover design for the FL will consist of the following: ♦ A one-foot thick foundation layer composed of select soil materials, a one foot (±) is in-place as interim cover. The depth of the interim cover will be verified and additional cover will be placed to achieve the one foot thickness. ♦ A three-foot thick layer of select soil material that will comprise the upper monolithic cover layer. Or: ♦ In lieu of verification of the one-foot of existing interim cover, a total of a four-foot thick layer of select soil material may be placed to comprise the foundation soil layer and the upper monolithic cover layer. This is the proposed approach to the Stage 1B Partial Final Closure Construction Project. A typical cross-section of the proposed alternative final cover system is shown on Figure 4 (see Detail 1). The alternative final cover configuration has been designed to: ♦ Ensure the containment of waste materials; ♦ Minimize the infiltration of water from rain and provide a vegetative cover of native shrubs and grasses; ♦ Prevent exposure of people and animals to waste; ♦ Limit landfill gas emissions; ♦ Minimize odor; ♦ Control fires; and ♦ Provide for an aesthetically pleasing appearance. The final cover was designed by a certified engineering geologist in accordance with State and Federal regulations and will be constructed in accordance with this PFCPCMP. Closure activities will commence upon approval of this PFCPCMP. 3.2.2 Final Cover Construction Clearing and Grubbing Prior to final grading and placement of the final cover, all existing vegetative materials will be removed from the surface without disturbing the underlying refuse. All deleterious Forward Landfill Stage 1B 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