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There are two observable wells on the property: an old irrigation well in a pump house adjacent to the north property line, directly north of the office building. The second observable well is a domestic well directly east of this irrigation well, approximately 165 feet. Another well is denoted as existing on the Site Plan, southwest of the irrigation well; however, this well was never located. As stated in the EHD Conditions of Approval,Item C: The EHD requires the abandoned well(s)be destroyed under permit and inspection by the EHD. It is my understanding that the domestic well to the east will be the well to serve this project. Consequently, this well was tested for this Study. All other wells on the property are to be destroyed under EHD permit. B. SOIL PHYSICAL AND CHENHCAL CHARACTERISTICS C The project site has level terrain; therefore, there will be no need to incorporate design considerations for slopes. The United States Department of Agriculture -Natural Resources Conservation Service(USDA-NRCS) shows the on-site soils to consist of Jacktone clay(#180). According to the USDA Handbook, the surface layer is a dark grayish brown clay loam with a hardpan of light gray clay below this surface soil. A hardpan of cemented silts and clays was not encountered in any of our test borings. The main limitations with the Jacktone soils are the slow permeability in the substratum, which was evidenced in the perc tests. Effluent that infiltrates and percolates through this fine soil material (clay and silt sized particles) will undergo biological treatment of the effluent before reaching the water table (-63 ft below grade). Biological treatment includes the destruction of bacteria and viruses. The surface and subsurface investigation of the soils under the subject property began with the use of a truck-mounted B-24 Mobile Drill Rig on October 15, 2004. Solid stem auger and a split-spoon sampler were used to 1.)Drill the 25 foot test boring to investigate the subsurface lithology to this depth, 2.) Sample soil for analysis from the 10 foot and 25 foot depths, 3.) Drill the 23 foot and 40 inch deep percolation test borings, where percable soil strata were determined from the test boring. A Log of Boring for the 25 feet deep test boring is found in Appendix 4. The log of boring for the 23 foot percolation test boring is found on the EHD PERCOLATION TEST RATE SHEET. Classification by the USDA and Unified Soil Classification System(USCS) includes aggregate base (AB), sandy loam (sandy silt/silty sand- SM/ML), a loam (silt-ML), a clay(lean clay- CL), a clay loam(CL/ML), and a sandy loam (silty sand -NIUSM). A Standard Penetration Test(SPT) was conducted at the 10 foot and 25 foot depths to illustrate the physical condition of the cohesive soils (silts and clays), and cohesionless soils (fine sands) found at these depths. The SPT test results indicate the subsurface soils consist of slightly dense cohesive soils. During the drilling procedures for the 25 feet deep test boring,no saturated soil conditions were encountered. Soil moisture content was consistently moist throughout the test boring. It is a slight possibility that perched water table conditions may exist above the static water table depth of 63 feet. Unfortunately, no Water Well Drillers Report (Well Log) for wells drilled on, or in close proximity LLobserved rty were available to observe the deep underlying lithology. No rust mottling was roughout the 25-foot soil profile, indicating no seasonal soil saturation. Rust mottling buted to geologic processes; however, it is usually due to seasonal soil saturation rcolating soil water encounters larger porosity soil and accumulates on top of these strata. hen anaerobic bacteria decompose organic matter and use iron (Fe ) in the metabolic Chesney Consulting