Laserfiche WebLink
12172 N Hibbard Road Project No. 2021-00063 P a g e | 3 <br />The surface and near surface soils located at the site are reported by the San Joaquin County Soil <br />Survey5 to be composed of the Galt clay, and Stockton clay, 0-2 percent slopes (Plate 5, Appendix <br />A). The table below presents some selected properties of these soils: <br />Table 1. <br />San Joaquin County Soil Survey <br />Elected Soil Properties of On-Site Soils <br />Soil Name <br />and Map <br />Symbol <br />Depth <br />(in)Unified Soil Classification <br />Salinity <br />mmhos <br />/cm <br />Soil <br />Reaction <br />pH <br />Perme- <br />ability <br />(in/hr) <br />Septic tank <br />absorption <br />fields <br />Galt clay, 160 <br />0-25: <br />25-34: <br />34-60 <br />Clay; CL, CH <br />Clay, Silty clay; CL, CH <br />Cemented, --- <br /><2 <br /><2 <br />--- <br />6.6 - 7.3 <br />6.6 – 8.4 <br />--- <br />0.06 – 0.2 <br />0.06 – 0.2 <br />--- <br />Severe: <br />cemented <br />pan, percs <br />slowly. <br />Stockton clay <br />250 <br />0-29: <br />29-37: <br />37-42 <br />42-60 <br />Clay; CL, CH <br />Clay, Silty clay; CL, CH <br />Clay; CL, CH <br />Cemented, --- <br /><2 <br /><2 <br /><2 <br />--- <br />7.4 – 8.4 <br />7.4 – 8.4 <br />7.4 – 8.4 <br />--- <br />0.06 – 0.2 <br />0.06 – 0.2 <br />0.06 – 0.2 <br />--- <br />Severe: <br />percs <br />slowly. <br />Note: The table descriptions do not necessarily reflect site-specific soil properties. <br />* See description of the map unit for composition and behavior characteristics of the map unit <br />3.2 Mass Transport Soil Properties <br />The clay and silty clay soil such as the layers reported for the San Joaquin soil at the site typically <br />provide a high degree of protection between percolating effluent at the surface and ground water <br />aquifers. Therefore, soils of this type typically present a low risk of excessive mass transport of <br />nitrate or other constituents of concern. <br />4.0 GROUNDWATER INFORMATION <br />4.1 Groundwater Depth and Gradient <br />The San Joaquin County Flood Control and Water Conservation District (2017 and 2018) <br />groundwater reports were reviewed to determine the groundwater levels near the Site. The Fall <br />2017 and Spring 2018 maps are the most current official maps available from the County. According <br />5 United States Department of Agriculture. Soil Survey of San Joaquin County, California. October 1992.