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J Tanc�3. ) The septic system that serves the Andrews' residence has been ning properly without any problems since they bought the property in 1979. Their house was built circa 1976. In 1991, an additional 36-inch diameter seepage pit was installed on the advice of the septic contractor who was pumping the Andrews' septic tank every other year. This permit for the seepage pit addition is found in Appendix D. The permit for the original system was not found in EHD files. ) The subject property is in an area designated as "Hardpan"by EHD's colo 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 110 feet, and the fact tha the shallow soil structure can be inadequate for proper effluent management, seepage pits and sumps are always allowed to be installed in this area. 3.. an 3. A review of Application Permits on microfiche file with EHD reveals there have I been five ppplications in the one-half mile radius study area for airs/Additions/Replacements to septic systems on 3ahant Road, and none on Bryant Road. (4 5. This can be considered a high number of Repairs/Additions/Replacements, and can be attribute to the indigenous clay soil type. Consequently, most effluent volume is managed by sumps or seepage pits in this area. Infiltrator Chambers® should be considered for installation as leachlines since the surface soils at typical leachline trench depth are extremely poor regarding permeability. Infiltrator Chambers may give a better opportunity for equal distribution of effluent, and promote evapotranspiration. (§ 5.1 and 6.0) SOIL PROFILE AND PERCOLATION TESTING /3 5.4)As noted on the USDA Soil Survey map, the on-site soils consist of Bruella sandy loams, #111 and#112. Typically, this soil types is moderately drained with very slow permeability at depths below 12 inches,where hardpan is present. As discussed below, the shallow perc tests for both Parcels had unacceptable percolation rates; however, the deeper perc tests had excellent ,fpe'rrcolation rates. {§ 5.2, 5.3, and 5.4) Logs of Boring using the Unified Soil Classification System (USCS), as observed from 25 foot borings completed on each of the two subject Parcels are found in Appendix C. In addition, soil logs are also found on the respective EHD PERCOLATION TEST DATA SHEETS. Generally, the soils show a consistent clay soil with a cemented silts hardpan within the shallow surface soils of the property. Silty clay was found predominately in the deeper test borings, except the referenced sandier material found at the perc test depths on both Parcels. Consequently, the deep percolation tests were set within a stratum at the highest encountered elevations where permeability was favorable. (§ 6.1) Percolation testing was conducted in the locations as illustrated on the Tentative Map found in Appendix C. As referenced, these test locations are where the future septic systems on both Parcels are anticipated to be installed and maintain sufficient distance requirements between wells, property lines, etc. The following information describes the preparation of the percolation test borings and the actual perc testing: Page -2- Chesney Consulting