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30 March 2022 AdvancedGeo Project No. 22-6800 An Employee- Owned Company Page 9 of 15� 7.0. CHEMICAL AND PHYSICAL PROPERTIES OF SOIL Soil chemical properties were supplied by regionally sourced material for the surrounding area. 7.1. CHEMICAL AND PHYSICAL PROPERTIES OF SITE SOILS The dominant soil composition in the general area of the property was inferred from information provided by the United States Department of Agriculture's Soil Geographic Database (USDASGD). The USDASGD soil survey indicates the soil type for the property is predominantly composed of Veritas fine sandy loam having 0 to 2 percent slopes (#266). The Veritas fine sandy loam is composed of alluvium derived from mixed rock sources. Soils are described as moderately well drained, with very low runoff, and salinity ranging from 0.0 to 4.0 millimhos per centimeter (mmhos/cm). The Veritas fine sandy loam typically features fine sandy loam from 0 to 54 inches bsg and cemented soils from 54 to 70 inches bsg. 7.2. MASS TRANSPORT PROPERTIES OF UNDERLYING SITE SOILS The percolation test and dominant soil type at the site indicates that the soils are semi- permeable and have moderate water storage. These soils will allow moderate infiltration of water through the surface soils. The longer the effluent remains near the surface, the more treatment is enhanced due to natural processes within the soil. If the permeable soils exist to the depth of the groundwater table, it is possible that surface contaminants may be transported fairly rapidly. 8.0. GROUNDWATER ANALYSIS The subject property is supplied with potable water by the onsite domestic water well located to the southeast of the existing residence (Figure 2). A groundwater sample was collected from the well and analyzed for nitrates as part of this study. 8.1. DESCRIPTION OF LOCAL GROUNDWATER According to the DWR SGMA Data Viewer for Spring 2021, depth to groundwater at the site is approximately 25 to 30 feet bsg. Between 2011 and 2021, depth to groundwater at the site has fluctuated between 20 and 40 feet bsg. Groundwater flow direction locally appears to be toward the northwest. Groundwater was not encountered in the 42 -inch - deep percolation test hole advanced on 24 March 2022.