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Geotechnical Engineering Investigation Page 12 of 24 New Residential Subdivision 2706 Pock Lane Stockton, CA 95205 March 30, 2021 CTE Job # 25-1097G CTE shall inspect and approve all structure over-excavations to confirm that adequate soil conditions have been reached. CTE shall also observe and perform testing during the placement and moisture conditioning of the engineered fill, placement and mixing of the lime/cement treatment materials; and the compaction of all engineered fill in building pad, pavement, and surface improvement subgrade areas to confirm that adequate soil conditions have been reached. Sections 5.2.1 and 5.2.2 present expansive soil mitigation measures recommended by CTE in order to reduce post construction structure and improvement movements and distress.Recommendations contained in Section 5.2.1 and 5.2.2 pertain to structural and non-structural support soils, respectively. 5.2.1 Structure Support Soils Subgrade materials in all proposed structure areas using a post-tension shallow foundation system can be lime treated as described herein to reduce differential movement caused by cyclic moisture change. The engineered fill in this lime treated zone should be consist of onsite soils moisture conditioned to at least 3% above optimum moisture and treated with high-calcium quicklime in accordance to ASTM C977. A 5% mixture by dry weight, a design unit weight of 120 pcf, and a 12-inch treatment depth is recommended (spread rate of 6 psf of lime). The lime treatment must be performed by a qualified soil stabilization contractor in general conformance with Caltrans Standard Specification Section 24. The lime product specifications and quality control test results must be provided to us prior to lime treatment grading operations. The lime should be initially spread and mixed with equipment capable of providing relatively uniform conditions and allowed to mellow overnight.The following day the lime treated should be remixed and compacted in place. After compaction, it is important to moist cure the lime treated exposed soils until placement of the subsequent slab aggregate base materials. If unanticipated, unsuitable materials are encountered at surface improvement subgrade or structure over-excavation such that proper compaction cannot be obtained, deeper over-excavations to remove such material may be required.