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inferred to be approximately 92 to 93 feet below ground surface (bgs). The same groundwater data indicates that area groundwater flows to the northwest. 2.4.3 Geology/Soils The subject property is situated within the Great Valley physiographic province of the State of California. The Great Valley is an alluvial plain about 50 miles wide and 400 miles long in the central part of California. Its northern part is the Sacramento Valley, drained by the Sacramento River and its southern part is the San Joaquin Valley drained by the San Joaquin River. The Great Valley is a trough in which sediments have been deposited almost continuously since the Jurassic (about 160 million years ago). In the Sacramento Valley, the Sutter Buttes, the remnants of an isolated Pliocene volcano, rise above the valley floor. Based on the review of the geologic map titled Geologic Map of the San Francisco-San Jose Quadrangle, California, prepared by the California Division of Mines and Geology and dated 1991, the subject property is mapped as the Pleistocene-aged Modesto Formation. The Modesto Formation consist of alluvium containing unconsolidated gravel, sand, silt, and clay. Based on information obtained from the USDA Natural Resources Conservation Service Web Soil Survey online database, the subject property is mapped as the Stockton Silty Clay Loam. This soil series is described as containing silty clay loam soil from the surface to 12 inches bgs, followed by clay (to 34 inches bgs), and clay loam (to 47 inches bgs); a cemented layer lies beneath the clay loam. The soil is listed as somewhat poorly drained with very low capacity to transmit water. This soil is further described as alluvium derived from mixed rock sources. 2.4.4 Flood Zone Information Partner performed a review of the Flood Insurance Rate Map, published by the Federal Emergency Management Agency. According to Community Panel Number 06077C0460F, dated October 16, 2009, the subject property appears to be located in Zone X, areas outside the 100-year and 500-year flood. A copy of the reviewed flood map is not included in Appendix B of this report. Phase I Environmental Site Assessment PARTNER Project No. 17-184702.1 May 10,2017 Page 6