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Phase II Additional Subsurface Investigation Tracy Comers Shopping Center 3225 North Tracy Boulevard Tracy,California 95376 Partner Project Number 14-129814.3 January 27,2015 Page 13 Geology and Hydrogeology Based on a review of the United States Geological Survey (USGS) Stockton, California Quadrangle topographic map, the subject property is situated at an elevation approximately 22 feet above mean sea level and the local topography is sloping gently to the southwest. Refer to Figure 2 for a topographic map of the site vicinity. The subject property is situated within the Sacramento Valley plain of the Great Valley physiographic province of the State of California. The uppermost geologic formation underlying the soils at the subject property is the Pleistocene Age San Joaquin formation. The San Joaquin formation comprises the underlying stratigraphy and consists mostly of clay loam deposited in stream channel, point bar, and fluvial environments. The thickness of the San Joaquin formation is estimated to be over 80 inches. Based on borings advanced during this investigation,the underlying subsurface consists predominantly of brown, dense, damp clay with some medium sand (CL) from the ground surface to approximately 10 feet below ground surface(bgs). At 10 feet bgs,the,subsurface consists predominantly of brown and red well- graded wet gravels (GW). Groundwater was encountered during this investigation between 9.1 and 10.2 feet bgs, and is inferred to flow to the east. Referto Appendix A for boring logs from this investigation: Subsurface Investigation Scope of Work Refer to Table 1 for a summary of the borings, sampling schedule and laboratory analyses for this investigation. The scope of the Phase II Additional Subsurface Investigation included the advancement of four borings (Bl through B4)for the collection of representative soil and/or groundwater samples. Field Activities Utility Clearance Partner delineated the work area with white spray paint and notified Underground Services Alert North (USAN) to clear public utility lines as required by law at least 48 hours prior to drilling activities. USA issued ticket number 010482 for the project. Permitting Prior to drilling, Partner secured Well Permit Number 71267 from the San Joaquin County Environmental Health Department for soil boring advancement. Refer to Appendix B for a copy of the permit acquired for this investigation. Health and Safety Plan Partner reviewed the site-specific Health and Safety Plan with on-site personnel involved in the project prior to the commencement of drilling activities. Drilling Equipment On January 13, 2015, Partner subcontracted with Environmental Control Associates, Inc. (ECA) (State of California C57 Water Well Drilling Contractor License Number 695970) to provide and operate drilling equipment. ECA, under the direction of Partner, advanced borings B1 and B2 with a direct-push, limited- PARTNER