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ENVIRONME14TAL SETTING NATURAL ENVIRONMENT Topography The project site is an area of level to gently rolling topography. Ele- vations range from approximately 100 feet above mean sea level in the northwest portion of the site to approximately 115 feet near the crests of several roll- ing highland areas. A branch of South Paddy Creek traverses the north end of the site in a generally east to west direction. Several minor local depres- sions occur which cause ephemeral ponding of runoff. Figure 4 illustrates the main topographical features of the site. Soils The Kleinfelder and Associates geotechnical report states that surface soils on-site consist of San Joaquin Loam, deep and San Joaquin Loam, poorly drained. These soils are medium textured and are generally underlain by hardpan or hardpan -like substratum. They are generally derived from alluvial deposits of mostly granitic materials. During our investigation, it was found that the U.S.D.A., Soil Conservation Service information, which was a source for the Kleinfelder report, has since been revised. The current soil designa- tions are shown on the following soils map. It must be recognized by the reader that the soil boundaries shown on the map are approximate and for discus- sion purposes only. Precise boundaries can only be established by.extensive field study which is not appropriate at this preliminary stage. Table 2 is a summary of on-site soils and their capabilities. The land capability units indicated in Table 2 may be defined as follows: IIIe3 Soils that are suitable for cultivation, but they have severe limitations that reduce the choice of plants and/ or require special conservation practices. Erosion suscep- tibility is the dominant problem. There is also a limita- tion caused by slow permeability or very slow permeability of the subsoil. IIIe8 Soils that are suitable for cultivation, but they have severe limitations that reduce the choice of plants and/ or require special conservation practices. Erosion suscep- tibility is the dominant problem. There is also a limita- tion caused by shallow depth of soil over hardpan. IVe8 Soils that may be used for some crops, but have very severe limitations that restrict the choice of plants and/or require very careful management. Erosion susceptibility is the dominant problem. There is also a limitation caused by shallow depth of soil over hardpan. Commonly referred to as marginal land.