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Mr. Horton Page 4 construction factors relevant to building a low permeability soil liner. These factors include destruction of soil clods, maximum allowable clod size, interlift bonding, water content of soil during compaction, degree of saturation, and the type and weight of roller. Appendix C, Part I B. 1. of Closure Operations states that moisture conditioning will occur after the soil has been removed from the borrow area and placed in the lifts for compaction. Water should be added to soils at least 24 hours before determining if the soil is at proper moisture content for compaction. This will allow the soils to fully absorb applied water so that moisture content is uniform throughout. Since the lifts are proposed at nine (9) inches thick, adding moisture just prior to compaction will not result in uniform saturation. Moisture conditioning is best accomplished on a mixing table or in the borrow area. The CQA Testing Protocol does not include any testing of the borrow material and relies on the 1987 Kleinfelder report which simply states that it is possible to achieve 10-6 cm/sec permeability by the proper blending of soils. As stated above, we suspect the permeability requirements will be difficult to achieve. As a result, CQA testing must be extensive to insure that permeability requirements are met. Borrow material should be tested in order to set up specifications and a procedure for determining a proper mix. Tests to insure a proper mix must be specified. A qualified soils person must be on site to direct the borrow material excavation and mixing to make certain that a proper mixture is achieved. The operator proposes to use in-house CQA personnel. The use of in-house Solid Waste Division staff to implement the CQA program is a conflict of interest according to the Regional Water Board. The Regional Water Board recommends third party CQA, although they do not require third party CQA. Review of the resumes of County (operator) personnel proposed for CQA work does not indicate experience in the area of low permeability soils construction. Use of County staff to implement the CQA program could be a violation of the Business and Professions Code. The relationship between permeability, density and water content must be established through appropriate field and laboratory tests. Unless these relationships are established, moisture content and density specifications for the clay layer have no basis.