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Califia LLC River Islands Phase 2 5044.000.008 Phase I Environmental Site Assessment 1.3 SITE AND VICINITY CHARACTERISTICS According to published topographic maps, the Property ranges in elevation from approximately 5 to 15 feet above mean sea level (msl). Review of the Wagner Geologic Map found that the Property is underlain by Holocene-aged Dos Palos Alluvium (Qdp), which primarily consists of flood basin and overbank deposits of sand, silt, and clay. Geocheck— Physical Setting Source Summary of the Environmental Data Resources, Inc. (EDR) report (Appendix A) indicated ten Federal United States Geological Survey (USGS) wells and three State water wells located within 1 mile of the Property. The wells had historic groundwater depth readings ranging from 6 to 51 feet below ground surface. We reviewed the Department of Water Resources On-line Water Data Library for depth to water in the vicinity of the Property. The website identified three wells within 1 mile of the Property. A well less than % mile south of the Property showed historic groundwater depth readings ranging from 4 to 10 feet below ground surface. Groundwater monitoring wells were installed throughout Stewart Tract in 1993 and 1999 by Roger Foot and Associates and Kleinfelder Inc., respectively. Seven of these wells remain in operation and have generally been observed to extend to depths of approximately 20 feet below the ground surface. The specific well installation methods and construction details are unknown. In 2005, 10 additional monitoring wells were installed by ENGEO within the Phase 2 area. Monitoring well data was generally used to determined seasonal high groundwater levels as well as to measure seasonal and annual fluctuations in groundwater levels and to observe groundwater gradients across the Property. In general, the groundwater levels tend to be the highest in the late spring (May/June) and the lowest in early winter (December/January). Typical high groundwater levels range from approximately elevation 4 to 7 feet(NAVD 88)and typical low groundwater levels range from elevation 2 to 5 feet (NAVD 88). The groundwater gradient generally follows topography and therefore generally trends from east to west across Stewart Tract. ENGEO performs on-going groundwater level monitoring and reporting on a quarterly basis under separate cover. For detailed groundwater level information, refer to the quarterly groundwater level reports and annual summaries, including the 2018 Groundwater Elevation and Surface Water Quality Results—Fourth Quarter, published January 24, 2019. The site-specific depth to groundwater and direction of groundwater flow was not determined as part of this assessment. Fluctuations in groundwater levels may occur seasonally and over a period of years due to variations in precipitation, temperature, irrigation and other factors. We reviewed the Department of Conservation, Geologic Energy Management(CaIGEM),formerly the Department of Conservation, Division of Oil, Gas, and Geothermal Resources (DOGGR), website and map database to determine if any historic oil and/or gas wells were located within the Property. Three wells were mapped within the Property and 22 wells were mapped within 1 mile of the Property. All 25 wells were identified as plugged, dry holes. ENGEO March 12, 2020 Expect Excellence-