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Two new installation permits are also found in the Appendix to illustrate the type of systems <br /> installed. Two permits were for the replacement of old septic tanks. <br /> The property is in an area designated as "Hardpan"by the EHD color designation map. Therefore, <br /> since the water table is comparatively deep, the installation of seepage pits with conventional <br /> leachlines are allowed and almost always installed in this area. As discussed below, the water table <br /> is approximately 93 feet below grade, according to the 1999 Lines of Equal Depth Map. <br /> SOIL PROFILES AND PERCOLATION TESTING <br /> As noted on the USDA Soil Survey map, the soil over the entire acreage consists of a Hollenbeck <br /> silty clay(#173), which is what was encountered in the surface soils during our drilling procedures. <br /> Typically, these soil types are well drained with slow permeability. There are sufficient soil "fines" <br /> to impede rapid percolation at leachline trench depth for treatment of pathogens to occur before the <br /> effluent reaches the water table. <br /> A Log of Boring designating the Unified Soil Classification System (USCS) soil classifications as <br /> observed from the percolation test borings are found on the EHD PERCOLATION TEST DATA <br /> FORMS. From the drilling of two test borings, it was found that heavy clay soils extend to depths <br /> of 25 feet on the south side of the dirt road (access easement) that divides the property into north <br /> half and south half sections. It was found from the perc test borings that the north half of the <br /> property possesses a sand stratum at the referenced depths encountered for percolation testing. The <br /> surface soils have a high clay content percentage and change color from dark brown to light brown <br /> at approximately 24 inches below ground surface (b.g.s.). The soil also has a high organic matter <br /> content and high moisture content. The USCS classifies the soil from the surface down to the <br /> encountered sand strata as CL-ML/CL-CH: a silty clay/lean clay and occasional fat clay, especially <br /> in the surface soil horizons. The sandier soils encountered at the deeper depths consist of an SM- <br /> SW: a silty sand and a well-graded fine-to-medium sand. Because the sand strata were encountered <br /> under the north half of the property at the noted depths,percolation testing was conducted near the <br /> north-center of each proposed Parcel. The test locations are measured and illustrated on the <br /> Tentative Map. The following information describes the preparation of the percolation test borings <br /> and the actual perc testing: <br /> On September 13, 2004, 0900 hrs, a truck-mounted B-24 Mobile Drill was used to drill one <br /> shallow and one deep perc test boring on each of the six designated Parcels, along with the two <br /> test borings referenced above. Solid stem, 4.5 inch dia. auger was used. After boring the <br /> shallow test holes, the sidewalls were scored with a pry-bar and the loose material removed with <br /> a hand auger. The deep borings could not be scored due to their depths. <br /> On September 23, 2004, 0800 hrs, the test borings were prepared for Parcels 4, 5 and 6 by <br /> placing two inches of fine gravel at the bottom of each boring, and then a three-inch dia. <br /> perforated PVC pipe was inserted. The test borings were pre-saturated with approximately 12 <br /> inches of clear water. Percolation testing for Parcels 4, 5 and 6 commenced on September 24, <br /> 0650 hrs, under EHD perc test Procedure#2. This four-hour test ensured maximum soil <br /> saturation. <br /> Page -2- <br /> Chesney Consulting <br />