ARCHIVED REPORTS_2019 SOIL MGMT PLAN (JULY-REVISED)

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Murphy Parkway Warehouse December 19, 2016 Job No. 146-618 Page 6 moisture content of at least optimum, and compacted. Fill placed in the building pad area at depths of more than two feet below the final soil building pad level should be compacted to at least 95 percent of the ASTM D1557 maximum dry density. All other fills should be compacted to at least 90 percent of the maximum dry density in accordance with the above standard. On-site soils are suitable for use as engineered fill provided the soils do not contain significant vegetable matter, rubble, rubbish, or other undesirable substances. Import materials, if any, should consist of sands, silts, or gravels with a plasticity index of ten or less and should be tested and approved by this firm prior to importation to the site. To enhance slab performance and provide a more stable base for working during the rainy season, the upper portion of the building pad and any adjacent concrete flatwork areas should be treated with portland cement. The treatment should extend at least five feet outside of building wall lines, or to the outer edges of surrounding portland cement concrete walkways or aprons, whichever is greater in extent. The soils should be treated to a depth of at least 12 inches with at least five percent portland cement as measured by dry unit weight of the compacted soil. The treated soil should be brought to a uniform over optimum moisture content, thoroughly mixed with the cement, and compacted to at least 92 percent of the maximum dry density determined by the ASTM D1557-02 test procedure. Not more than three hours should elapse between the time the cement is mixed with the soil/water and final compaction is completed. The above concentration of treatment chemical are based on assumptions made regarding the soil composition of the upper 12 inches of the building pad. Some modification to this concentration may be required. The percentage and type of treatment chemical be used should be established by our engineers based on a review of the types of soils present on each area to be treated. Treatment should conform to applicable provisions of the Caltrans Standard Specifications, Sections 24 and 27. The treated pad should either be kept wet for a period of at least three days after compaction or seal coated. Untreated pavement subgrades, if any, should be compacted to at least 90 percent of the ASTM D1557- 02 maximum dry density regardless of whether the final grade is achieved by cutting, filling or left at final grade. Permanent excavation and embankment slopes should not exceed an inclination of one vertical on two horizontal. A representative of this firm should be present during grading operations to test and observe earthwork construction. FOUNDATIONS The proposed building may be supported upon continuous and/or isolated spread foundations based in undisturbed or recompacted natural ground, engineered fill, or a combination of these materials. Building foundations should extend to a minimum depth of 18 inches below the building pad. Foundations in dock areas should extend at least 12 inches below the lowest surrounding soil subgrade level. Foundation excavations should be observed by an Engineer from this office to ensure that proper bearing soils are engaged. A minimum foundation width of 12 inches should be maintained. Foundations so established may be designed for maximum allowable soil bearing pressures of 2000 pounds per square foot (psf) for dead load, 2500 psf for dead plus live load, and 3300 psf for total load including the effects of wind and seismic forces.