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SECTION 4 Results 4.1 Soils _ 4.1 .1 San Joaquin County The Soil Survey of San Joaquin County, California, (SCS, 1992)and the Soil Survey of Stanislaus County, California, Western Pan(NRCS,2002) shows seven soil series within the project site (Figure 2).None of the soil series is considered hydric;however, some of the soil series have hydric inclusions(SCS, 1995;NRCS,2004). These soil units occur on slopes ranging between zero and 2 percent. The Capay clay,the Zacharias clay loam,and the Zacharias gravelly clay loam occupy most of the north and northwest sections of the site. The Vernalis clay loam and the Cortina gravelly sandy loam overlie the remainder of the site,with interspersed areas of the other mentioned soil types. The following is a brief description of mapped soils within the study area: • Capay clay,zero to 2 percent slopes, is not listed as hydric by NRCS(2004). This ` very deep,moderately well-drained,nearly level soil is in interfan basins. It formed in alluvium derived from mixed rock sources. In a typical profile,the surface layer is grayish-brown and dark grayish-brown clay about 20 inches thick. The subsoil to a depth of 60 inches is grayish-brown,dark grayish-brown,dark brown, and pale brown clay. The soil is calcareous below a depth of 20 inches. In some areas,the surface layer is silty clay. Included in this unit are small areas of Stomar and Vemalis soils in the slightly higher landscape positions and Willows soils in the slightly lower positions.Also included are small areas of fine-textured soils that have a perched water table at a depth of 48 inches and may be saline-sodic in some part. Included areas make up about 15 percent of the total acreage.Although the Willows inclusion •� is listed as hydric by NRCS(2004),this inclusion was not documented during soil analysis in the field.Permeability is slow in the Capay soil.Available water capacity is high.Runoff is slow,and the hazard of water erosion is slight. • Cortina gravelly sandy loam,zero to 5 percent slopes, is not listed as hydric by NRCS(2004).This very deep,somewhat excessively drained,nearly level or gently r„ sloping soil is on alluvial fans.It formed in alluvium derived from mixed rock sources.In a typical profile,the surface layer is brown, gravelly,sandy loam about 18 inches thick.The underlying material to a depth of 60 inches is pale brown, stratified,very gravelly, sandy loam and very gravelly loamy sand.In some areas,the surface layer is gravelly loam or gravelly clay loam.Included in this unit are small areas of Cortina soils that have slopes of 5 to 8 percent and Vernalis and Zacharias soils on the slightly higher parts of the landscape. Also included are areas of Vemalis Qua"Mining and Reclamation Project 4-1 ESA/203015 Wetland Delineation Report Fe0ruary 2006