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The topography of the farmable land is approximately 87 to 82 ft above MSL, east to west, and relatively level as depicted on the Tentative Parcel Map. Therefore, septic system design criteria for slopes will not have to be considered. (§3.1,3.2,3.3, and 3.4) Located in Appendix D, are three permits for additions/supplementary drainage to on-site septic systems, indicating the surface soils are poor for effluent management. Four additional permits are also included in Appendix D for the installation of on-site septic systems indicating the type of septic system structures installed. (§3.4) The subject property is in the area designated as "Clay"and"Hardpan" by EHD's map denoting the various soil types and septic system requirements throughout the County. As referenced below, the water table is relatively deep in this locale at approximately 90 feet. EHD septic system requirements in this area are leachlines and sumps or seepage pits,based on the number of bedrooms any applicable structure has or will have. (§ 5.4) Since the shallow soil characteristics at typical sump depth are inadequate for proper effluent management, seepage pits should be installed on the property instead of sumps because of the failing perc test results obtained at typical sump depth. (§3.5,3.6,� -A review of Application Permits on file at EHD reveals there has been one Application or Repairs/Additions/Replacements to septic systems in the one-half mile study area on Van Allen Road. (§ 5.1 and 6.0) SOIL PROFILE AND PERCOLATION TESTING (§ 5.4) The USDA Soil Map shows the on-site soil to consist predominately of a Madera sandy loam with hardpan. Typically, this soil type is well-drained but with slow permeability when percolating water encounters underlying hardpan, according to the N.R.C.S. This slow permeability was confirmed in the deeper perc test results representative of sumps, but not in the shallow perc test representative of leachlines. Sufficient soil "fines" (clay particles)exist to impede rapid percolation. Therefore, treatment of septic effluent can take place before reaching the water table at approximately 90 feet below grade. (§ 5.2, 5.3,1nd 5.4) A Log of Boring using the Unified Soil Classification System (U.S.C.S.), -observed in the 90-inch deep perc test boring, is found on the EHD PERCOLATION TEST DATA SHEET. Generally, the underlying surface soils show a consistent very fine sandy silt/silty clay soil. Cemented silts hardpan stratum was discernible at depths down to typical sump depth of �— approximately 72-90 inches. (§ 6.1) There is no proposal to build anywhere on the subject property. Percolation testing was conducted in the locations illustrated on the attached Tentative Map, near the ditch that flows through the property. The test locations maintain sufficient distance requirements between this ditch and the proposed property lines. The following information describes the preparation of the percolation test borings and the actual percolation testing: Page -3-