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GEe #5130 - Page 5 Fill placed to attain proposed foundation and slab elevations (both base- ment and garage) should be an engineered fill. An engineered fill consists of inorganic soil compacted to a specified density under the technical supervision of a soil engineer. The inorganic soils at the site may be used as fi 11 . Fill placed to achieve slab and footing elevations should be placed in relatively thin lifts and mixed and spread evenly. Each lift should be thoroughly and uniformly compacted to at least 95% of the maximum standard Proctor density. HUO also requires density tests (compaction tests) to ascertain compliance with compaction specifications. If the results of the density tests indicate inadequate compaction, the area should be reworked until the results of the field density tests indicate adequate compaction. Footings constructed on basal soils or fill placed in accordance with our recommendations may be designed using a maximum design bearing pressure of up to 2000 psf. Basal Soils Where basal soils are exposed at normal footing elevation, the footings may be constructed on the firm (N-values of 4 or more) basal soils without any special earthwork needed. In our opinion this is at borings #1 and #3. Basal soils with N-values less than 4 were encountered in borings #2, #4, and 115. Additional borings and tests should be done to delineate areas where these basal soils are present. It is our opinion that the subsurface conditions are marginal at borings 112, #4, and #5 where these basal soils are present below proposed buildings. The basal soils may be subject to consolidation and settlement. The weight of fill placed below and around buildings, and the weight of the buildings will compress the basal soils. This compression will result in settlement at the surface, which in turn, could lead to adverse movement and cracking in the building. The compression should occur rapidly because the basal soils are granular.