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2.0 Environmental Setting 2.1 Regional Physiographic Setting A United States Geological Survey (USGS), [Stockton West, California] 7.5 Minute Topographic Quadrangle map of the subject property and surrounding vicinity was reviewed. The elevation of the property is approximately 12 feet above mean sea level (MSL). Topography at the subject property is relatively flat and declines gently to the west. The project location on a topographic map is depicted on Figure 1 at the end of this report. 2.2 Geology/Soil Conditions The subject property is located within the Great Valley of California. The Great Valley is a north-south trending structural trough bounded by the tilted block of the Sierra Nevada Mountains to the East and the folded and faulted Coastal Ranges to the West. According to a geologic map of the area, the soils underlying the subject property are part of the Quaternary aged Modesto Formation (California Division of Mines and Geology, 1991). The Modesto Formation consists of fluvially deposited sands, silts, and clays that vary in thickness from 10 to 200 feet. Subsurface soils encountered during the current investigation included sand, clay, and silt, to a depth of 35 feet bgs (the maximum depth explored). 2.3 Hydrogeology The subject property is located within the Eastern San Joaquin Subbasin of the San Joaquin Valley Groundwater Basin. The Eastern San Joaquin Subbasin consists of unconsolidated to semi consolidated sedimentary deposits bounded by the Mokelumne River to the north, the San Joaquin River to the west, the Stanislaus River to the south, and consolidated bedrock of the Sierra Nevada Mountains to the east (DWR Bulletin 118, 2004). Groundwater was encountered at a depth of approximately 23 feet bgs during sampling activities. The groundwater flow direction beneath the subject property is not specifically known; however data obtained from the State Water Resources Control Board's GeoTracker database indicates the presence of a closed Leaking Underground Storage Tank (LUST) site (California Tank Lines, addressed 3105 El Dorado Street) approximately 0.8 miles southeast of the subject property. Based on recent groundwater sampling events in 2020 and 2021, groundwater at the subject property can be inferred to flow in a westerly direction. Phase II Limited Subsurface Investigation Fulcrum Resources Environmental 2546 Turnpike Road,Stockton, California 95206 202107-8656 6