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7system nd with this one Repair/Addition permit, is the permit for the installation of the septic hich currently serves the existing mobile home on proposed Parcel 1. This installation was oneonMay 11, 1993 and consists of two 80 foot leachlines and two 36-inch diameter seepage pits. There has not been any problems with this mobile home system, or the Van Vuren's residential septic system,which has been operational for over 35 years. The subject property is in an area designated as"Hardpan"by EHD. Therefore, since the water table is comparatively deep in this area, seepage pits and sumps are allowed to be installed. As discussed below, the water table is approximately 103 ft below grade. SOIL PROFILE AND PERCOLATION TESTING The USDA Soil Survey Map shows the property consists of only one soil type: Hollenbeck silty clay(#173). An intermittent hardpan stratum also exists. Typically, these soil types are well drained with very slow permeability. There are sufficient soil"fines"to impede percolation so treatment of effluent can occur before reaching the water table, unlike what would be encountered with a very sandy soil. Logs of Boring designated by the Unified Soil Classification System (USCS), as observed from the percolation test borings drilled for the perc tests, are found on the EHD PERCOLATION TEST DATA SHEETS. Generally, the soils show distinctive physical characteristics. Surface soils change color from dark brown to light brown at approximately 24 inches below ground surface (b.g.s.). The USCS classifies the surface and subsurface clay soils as CL and CH - lean clays and fat clays. Remaining soils consist of gravelly clay and sandy clay. The soil has a low organic matter content and very high moisture content. Subsurface soils on Parcel 2 consist of a sandy silt, silty sand(ML, SM) in the area of testing. Percolation testing on proposed Parcel 1 was done in an open area directly north of the driveway to the Van Vuren's house. This was the only open area on the Parcel. Percolation testing was conducted on Parcel 2 in the only location that was feasible, since the entire parcel had recently been irrigated. This is the only area that does not become inundated with irrigation water since the elevation is high enough to prevent water from reaching this point. The test location is 200 feet north of Little Johns Creek and 25 feet from the west property border, as illustrated on the attached Tentative Map. The following information describes the preparation of the percolation test borings and the actual perc testing: On May 19, 2005, one shallow and one deep perc test boring were drilled on proposed Parcels 1 and 2 with a B-24 truck-mounted drill rig. The two shallow borings were both drilled to 42 inches, while the deep borings were drilled to 25 feet on Parcel 1 and to 10.5 feet on Parcel 2. The sidewalls of the shallow borings were scored with a pry-bar and the loose material removed. Two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted. Although the soil was very wet from the heavy rainfall this past winter, the test borings were pre-saturated with approximately 12 inches of water. Page-2- Chesney Consulting