SU0010434 SSNL - Laserfiche WebLink

Home Browse Search

Soil Profile and Geologic Information The Site is mapped on the Geologic Map of California: San Jose sheet (Rodgers, 1966). It is depicted within map units of Great Valley fan deposits and Pleistocene nonmarine material (Plate 7). The surface and near surface soils located at the Site are reported by the Soil Survey of San Joaquin County, California (USDA, 1992) to be composed of Capay clay (Plate 8). The table below presents some selected properties of this soil: Table 1. Selected Properties of On-Site Soils (USDA, 1992) Soil Name Depth Unified Soil Salinity Soil Perme- Septic tank and Map (in) Classification mmhos/cm Reaction ability absorption Symbol pH (in/hr) fields Capay Clay, 0-20: Clay: CH, CL <2 6.6 - 8.4 0.06 - 0-2 Severe: 0-2% 20-60: Clay, silty clay: CL, CH <2 6.6 - 8-4 0-06-0.2 peres slowly slopes, 118 Capay Clay, 0-20: Clay; CH, CL <4 6.6- 8.4 0.06 - 0.2 Severe: wet, 0-2% 20-44: Clay, silty clay: CH, CL <4 6.6 - 8.4 0.06 - 0.2 peres slowly slopes, 121 44-60: Silty clay loam. clay <4 6.6 - 8.4 0.06- 0.2 loam: CL Note: The table descriptions do not necessarily reflect site-specific soil properties. See description of the map unit for composition and behavior characteristics of the map unit. Soil Borings On March 31, 2015, Live Oak excavated a shallow soil boring on the proposed homesite parcel the Site for the purpose of conducting a percolation test. The boring was four inches in diameter, 3.45 feet deep, and was excavated by hand auger (Table 2). The location of the boring is indicated on Plate 9. The soil in the boring was similar to that described by the Soil Survey. Clay was encountered to a depth of 2.5 feet, followed by clay with sand to the full depth of the hole. The soil log is presented on Plate 10. Discussion of Soil Lithology Based on the soil observed in the boring, there appears to be moderate potential for percolation in the shallow soil zone at the test location. Sandy soils generally have a much greater potential for percolation than fine-grained or cemented soils. However, a percolation test is the only accepted method for determining the suitability of the soils for a septic disposal area. Percolation test results are discussed in the following section. LOGE 1502 Page 5