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§3.0 EXISTING AND PROPOSED SEPTIC TANK USAGE §3.1, §3.2, §3.3 and §3.4. The septic system for the Darwin Inman residence was installed in February 1950. In 1979, an additional 40 feet of leachline and a 36-inch diameter seepage pit was installed. In February 1995, the septic system for the Silva residence was installed, composed of leachlines and sumps. It has been functioning properly since installation. Permits for these systems are found in Appendix D. §3.4. The subject property is in an area designated as"Hardpan"by EHD's colored map denoting the various soil types and septic system requirements throughout the County. §5.4. Therefore, since the water table is deep in this area at approximately 70 feet, and the fact that the surface soil structure can be insufficient for proper effluent management, seepage pits and sumps must be installed in this area. §3.5 and §3.6. A review of Application Permits on file with the Environmental Health Department reveals there have been five Applications for Repairs/Additions to septic systems within the one-half mile radius study area from the subject property. There have been more than 15 Applications for Repair/Additions on all of Steinegul Road. §5.4. This can be considered a very high number of Repairs/Additions/Replacements, and can be attributed to the indigenous clay soil type, particularly north of the subject property. Consequently, the majority of effluent volume is managed by sumps or seepage pits in this area. §5.1 and §6.0 SOIL PROFILE AND PERCOLATION TESTING §5.1 and §5.2 As noted on the USDA Soil Survey map,the surface soils are composed predominately of a Madera sandy loam (#193),with the extreme northwest portion consisting of Madera-Alamo Complex (#195). Permeability is very slow in both soil types,primarily due to an underlying claypan/hardpan. A high shrink-swell potential also exists. Consequently, consideration should be given to having a soils engineer assess the on-site soils to provide foundation recommendations if construction will ever take place on the Parcels. §5.2 and §5.3. Logs of Boring designated by the Unified Soil Classification System (USCS), as observed from each of the perc test borings, are found on the respective EHD PERCOLATION TEST DATA SHEETS. Generally, the surface soils (<5 ft) are very compact with hardpan and clays, while the deeper soils possess much greater permeability. The percolation test borings were set within strata where permeability was most favorable at the highest elevation. Percolation testing was conducted on proposed Parcels 1 and 2 as illustrated on the Tentative Map found in Appendix C. These locations maintain sufficient distance between future septic systems that may be installed, and existing wells. The following information describes the preparation of the percolation test borings and the actual perc testing: §6.2, §6.3 and §6.5. On June 18, 2005, 1230 hrs, one shallow perc test boring and one deep test boring was drilled in the referenced locations. Page-2- Chesney Consulting