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(§ 4.2) Any of the above land use could create environmental concerns that may be discovered in the future. As evidenced by the testing of the on-site domestic well and discussed in Section 4.0, the groundwater nitrate concentrations are very low and the agrichernical Dibromochloropropane (DBCP) is non-existent. The topography of the site is approximately 75 feet above MSL 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) The north septic system that serves the main residential structure was1- repaired/replaced in July 2004, with the permit found in Appendix D. Two leachlines and four 25 . �f ft deep seepage pits were installed. There is an existing septic system at the south end of the 3 3> house that serves a bathroom on this side of the structure. (§3.4) The subject property is on the border of 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 ( 'J 125 feet. EHD septic system requirements in this area are leachlines and sumps/seepage pits, Cay based on the number of bedrooms the applicable structure has or will have. (§ 5.4) Since the shallow soil characteristics at typical sump depth are adequate for proper 11 effluent management, sumps should be considered for installation instead of seepage pits because of the proximity to the Calaveras River. (§ 3.5 and 3.6) A review of Application Permits on microfiche file at EHD reveals there has been one Application for Repairs/Additions/Replacements to septic systems in the one-half mile study area on Jack Tone Road. This permit can be found in Appendix D. (§ 5.4) (§ 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 as Archerdale clay loam (#107). Typically,these soil types are well-drained, but with slow permeability according to the N.R.C.S. This slow permeability was confirmed in the shallow perc test result, but not in the deeper perc test representative of sumps. 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 125 feet below grade. (§ 5.2, 5.3, and 5.4) A Log of Boring using the Unified Soil Classification System (U.S.C.S.), as c observed in the 105-inch deep perc test boring, is found on the EHD PERCOLATION TEST �52� DATA SHEET. Generally, the underlying surface soils show a consistent very fine sandy silt/ silty clay soil with a high degree of stickiness. No cemented silts hardpan stratum was discernible at depths down to the typical sump depth. Nearby well logs observed in the microfiche files at EHD could not be printed. However, the logs reveal intervening strata of sand, clay and gravel. Page -2- Chesney Consulting