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28 September 2022 Project No. 22-6994 Page 5 of 15 AdvancedGect An Employee-OwnedCompany in age from Jurassic to present day, creating a nearly flat -lying alluvial plain extending from the Tehachapi Mountains in the south to the Klamath Mountains in the north. The western and eastern boundaries of this province are comprised of the California Coast Range and the Sierra Nevada, respectively. Geologically, the area around the property generally consists of Holocene -aged flood -basin deposits of clay, silt, and sand. Miocene to Holocene age -units are located in the surrounding area. These deposits are heterogeneous mix of generally poorly sorted clay, silt, sand, and gravel with some beds of claystone, siltstone, sandstone, and conglomerate. Most of the fresh groundwater in the Central Valley is contained in the post -Eocene -aged continental rocks and deposits and in the Holocene -aged River deposits consisting of gravel, sand, silt, and minor amounts of clay. In general, these geologic materials comprise a major widespread aquifer extending hundreds of feet deep and occasionally containing individual confining layers. The Modesto, Riverbank, Turlock Lake Formations and overlying recent alluvium are the principal source of domestic groundwater in the 13,500 - square mile San Joaquin Valley Groundwater Basin (Basin 5-22). This basin is drained primarily by the San Joaquin River, which is approximately 15 miles southwest of the subject property. The nearest surface water feature to the site is the Littlejohns Creek, which is approximately 0.5 miles north of the subject property. 4.1. GROUNDWATER DESCRIPTION FOR THE GENERAL AREA According to the State of California Department of Water Resources (DWR) Sustainable Groundwater Management Act (SGMA) Data Viewer, Seasonal Report for Fall 2021, depth to groundwater at the site is approximately 90 to 95 feet below surface grade (bsg). Between 2011 and 2021, depth to groundwater at the site has fluctuated between approximately 70 and 100 feet bsg. Groundwater flow direction locally appears to be toward the northwest. Groundwater was not encountered in the 40 -inch -deep percolation test hole (P-1) advanced on 14 September 2022 nor the 118 -inch -deep percolation test hole (P-2) advanced on 26 September 2022. 4.2. GROUNDWATER CONTAMINATION IN THE AREA OF THE SITE The immediately adjacent and outlying land use for the parcel is residential and agricultural. Potential groundwater contamination can occur from several sources including leaking underground storage tanks, septic systems, agricultural activities, dairies, and stormwater infiltration. A review of the California Department of Toxics and Substances Control (DTSC) EnviroStor Database and the California Geotracker Web site did not reveal any Leaking Underground Storage Tank (LUST) sites or other environmental investigations within 0.5 miles of the site.