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�. Spiess Rancho Subdivision Page No. 3 _ on the soil logs. The boring legend is presented on Plate No. 9 . The soils encountered in the test pits and test holes were fairly consistent throughout the site. The surface soil consisted of a medium dense fine sandy silt which varied in depth from 0 . 5 to 2 . 5 feet. The top 4 inches of this had a fairly heavy root growth from the pasture grasses and alfalfa. The surface soil was _ underlain by a 1 to 2 foot stratum of stiff sandy clay which in turn was underlain by a cemented and dense silty sand (hardpan) . The hardpan was underlain by various strata of sandy clay, sandy silt, and silty clay. For a more detailed description of the soils encountered in the test pits and holes see the soil logs. Soil logs show subsurface conditions at the date and location indicated and it is not warranted that they are representative of subsurface conditions at other locations and times. No ground water was encountered in the test pits or test holes at the time they were excavated. V DESIGN STUDIES AND RECOMMENDATIONS From a soil engineering standpoint, it is our opinion that the site is suitable for development of the proposed subdivision, however, all of the conclusions and recommendations presented in this report should be incorporated in design and construction to avoid soil and foundation problems. The main item of consideration _ is the expansive nature of the near surface clay soil. At most of the test holes, the subsurface clay soils were deep enough that they should not affect proposed foundations and slabs, however, in several of the test borings the clay soils were close enough to the surface (6 inches) that special foundation treatment will be required. The depth of the clay soils can and will vary between test holes. Special foundation treatment should be in the form of pre- saturation of the slab subgrade prior to slab placement. Experience has shown that if the slab subgrade is in a near saturated condition prior to casting, and the foundations act as a continuous cut-off wall, moisture fluctuations under the slab are minimized and movement of the slab should be within acceptable limits. The determination of whether pre-saturation is required may best be made by performing a footing inspection after the _ footing excavations have been completed, but before any reinforcement or forms have been set. P GERSO� D '^ P 9SS O G�