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On the basis of the soil conditions modeled, soils suitable for use in the FSL closure final cover can be generated by select excavation of soils from the proposed borrow source adjacent to the site. In order to generate adequate performance characteristics, the final cover materials should be mixed to exhibit a grain size distribution that generally excludes particles in excess of 3 inches. In addition, soil excavation and placement operations should be conducted so as to yield a minimum fines content (% by weight passing the No. 200 sieve) of 70, a minimum of at least 30% finer than 5 -microns and an as -built saturated hydraulic conductivity of less than 1x10'6 cm/s. As indicated above, sufficient borrow materials are likely to be available from the borrow source to meet the project specifications (Figure 1). A quality assurance plan describing the materials testing methods and procedures, testing frequencies, and materials specifications for an alternative final cover system placed over the FSL is presented as Appendix D. Moisture monitoring should be conducted in accordance with the recommendations presented in the monitoring workplan (Appendix E). 7.0 CONCLUSION Based on the data presented herein, it is concluded that a 4 -foot thick monolithic final cover section constructed as described above will satisfy the regulatory requirements for an alternative final cover as defined in CCR Title 27. More specifically, the conditions summarized above are believed to effectively demonstrate that a prescriptive cover is not feasible at this site and that the proposed alternative final cover will provide equivalent protection against water quality impairment at a reduced cost. EMIEM�JC This report is based on the project as described and the geotechnical data obtained in this study. Our firm should be notified of any pertinent change in the project plans or if conditions are found that differ from those described in this report, since this may require a revaluation. This report has not been prepared for use by parties or projects other than those named or described above. It may not contain sufficient information for other parties or other purposes. This report has been prepared in accordance with generally accepted geotechnical practices and makes no other warranties, either express or implied, as to the professional advise or data included in it. Geologic Associates Luis A, �Manseal Staff Engineer, EIT LAM/GLL/lkl -12- C:\2005.0082\FOR WARD/ForwardCOV&R.DOC\T/1 S/2005 Gary L. Lass, RG, EG, HG President Geologic Associates