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indirect risks to life or property? e) Have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems where sewers are not available for the disposal of wastewater? f) Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature? NARRATIVE DISCUSSION Environmental Setting The project site is in the Central Valley, which is a topographically flat, northwest - trending trough about 50 miles wide and 450 miles long. The Geologic Map of the San Francisco -San Jose Quadrangle designates the underlying geology of the project site as the Modesto Formation (Wagner et al. 1991). The Modesto Formation, ranging in depth from 10 to 200 feet, consists primarily of sand, silt, and clay seams deposited by rivers (DWR 2014). A custom soil survey indicates that Jacktone clay underlies essentially the entire project site — a very small sliver of land in the southwestern corner of the 3009 Pock Lane site has soil that consists of a mix of Jacktone clay and urban land. Jacktone clay is a somewhat poorly drained soil also formed in alluvium from mixed rock sources, and it is moderately deep to a hardpan. Permeability and runoff of this soil are slow, and the water erosion hazard is slight. Jacktone clay has a high expansive, or "shrink -swell", potential (SCS 1992, NRCS 2021). Expansive soils can change dramatically in volume depending on moisture content, affecting structures and infrastructure such as water and sewer lines. There are several faults and potential fault traces located within San Joaquin County, concentrated along its eastern and western margins. No active or potentially active faults have been identified in the Stockton vicinity - the nearest active fault is the Greenville Fault, approximately 22 miles west-southwest of Stockton. (City of Stockton 2018). However, San Joaquin County is in a region that lies between two areas of seismic activity - the San Andreas Fault System of the greater San Francisco Bay Area to the west, and the Foothills Fault System in the Sierra Nevada foothills to the east. Active faults associated with the San Andreas Fault System include the Concord, Calaveras, Hayward, and San Andreas faults, all of which can cause ground shaking that could potentially be felt within the County (San Joaquin County 2016a). Paleontological resources are fossils or groups of fossils that are unique, unusual, rare, uncommon, or important, and that add to an existing body of knowledge in specific areas. Surface examination of a study or project area often does not reveal whether paleontological resources are present. A record search of the Museum of Paleontology at the University of California in Berkeley indicated that 97 paleontological finds have been made in the County (UCMP 2020). Most specimens from the County have been found in rock formations in the foothills of the Diablo Mountain Range. However, remains of Pock Lane Public Review Draft IS/MND 3-30 May 2022