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F the attached USGS Map, and the Tentative Map, the topography of the site is 145- MSL, with the land declination toward the east and south. Future septic system or slopes may have to be considered if a house is built on a severe slope greater (§ 3.1, 3.2,3.3, and 3.4) The septic system that serves Mr. Olson's residence has been functioning properly without any problems since the house was built in 1975. This may be attributable to the indigenous sandy soils that are found down to 17 feet. ,"-(§3.4) The subject property is in an area designated as "Hardpan Soils"by EHD's map denoting the various soil types and septic system requirements throughout the County(hardpan soils were not encountered in the test borings). (§ 5.4) Since the water table is deep in this area at approximately 150 feet, and the fact that the shallow and deeper soil structures are adequate for proper effluent management, seepage pits are allowed to be installed in this area, and usually are. v (§3.5 and 3.6) A review of Application Permits on microfiche file at EHD reveals there have been four Applications for Repairs/Additions/Replacements to septic systems on Mackville Road within the one-half mile radius study area. (§ 5.4) This can be considered a high number of Repairs/Additions/Replacements permits considering the low density housing and may attributed to the indigenous clay soil types that can be found in the shallow soils and the deeper soils. (§ 5.1 and 6.0) SOIL PROFILE AND PERCOLATION TESTING (§ 5.4) The USDA Soil Map shows the on-site soil to consist of a Ramoth sandy loam (#216) and Rocklin fine sandy loam (#229), with the vineyard composed completely of the Rocklin sandy loam. Typically, the Ramoth soil is very deep and well-drained, with moderately slow permeability in the shallower soils. The Rocklin soil is moderately well-drained, also with moderate permeability. Sufficient soil "fines" exist in both soil types to impede rapid percolation. Therefore, treatment of septic effluent under unsaturated flow conditions can take place before reaching the water table. As discussed below, the shallow perc tests had excellent percolation, which is indicative of the encountered soil types, as noted below. -(§ 5.2,5.3, and 5.4) A Log of Boring using the Unified Soil Classification System (USCS), as observed in the 25 ft deep percolation test boring completed on Parcel 1 near the existing leachfield area, is found on the EHD PERCOLATION TEST DATA SHEET. Generally, the underlying soils show a poorly graded silty sand to five feet, with a well-graded medium silty sand from five to 17 feet. At 17 ft, a clayey silt/silty clay was encountered to the boring depth of 25 ft. `(§ 6.1) Percolation testing was conducted in the locations as illustrated on the Tentative Map found in Appendix C. As referenced, the perc test location for Parcel 1 is south of the existing house, near where the existing leachfield is located. This test location maintained sufficient distance requirements between wells, property lines, etc. The following information describes the preparation of the percolation test borings and the actual percolation testing: Page -2- Chesney Consulting