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1 7ofdeeper percolation testson Parcel C also exhibited acceptable permeability. Pere test. ummarized and illus ow Table 1 below. Sufficient soil "fines" exist within the encountered soil to impede rapid percolation, which would occur in a sandy soil. Therefore, treatment of septic-effluent can take place within this soil environment before reaching the deep water table. (§ 5.2, 5.3, and 5.4) A Log-of Boring using the Unified Soil Classification System (USCS), as observed from the deep pere.test borings completed on each of the four proposed Parcels is found on the EHD PERCOLATION TEST DATA SHEET. Generally, the underlying soils show a dark brown clayey silt-silty.clay.with very fine sand down to four feet, and then progressing to a light brown, fine sandy silt.: Cemented.silts hardpan was encountered in all of the test borings beginning at approximately eight feet below.grade. Hardpan density varied from soft to severe.in the deeper test borings, and was notably soft in the Parcel C deep test. Below approximately 12 feet is clay soil down to 25 feet. (§ 6.1) Percolation testing was conducted in the locations as illustrated on.the Tentative Map and SJC Parcel Viewer Map,found in Appendix 3.: These test-locations maintain sufficient distance requirements between wells-and property lines. Test sites were determined by the owner of the property, Mr. George Nahas, and based upon where he anticipates the future siting of residential - structures...He is aware that if the structures are situated outside of the 100-foot radius from the pert tests conducted for.this..study, EHD can require additional perc testing in the new location(s). The following information describes the preparation of the percolation test borings and the actual percolation testing: (§ 6.2, 6.3.and 6.5) On Monday, May 10, 2010, 0900 hrs, shallow perc test borings of 40 and 42 inches and deeper borings of 11.5 and 10.25 feet were drilled on Parcels A and B. On Tuesday, May 11, 2010, 0900 hrs, shallow perc test borings of 40 inches and deeper borings of 10.75 and 11.5 feet were drilled on Parcels C and D. The sidewalls of each shallow boring was scored with a pry-bar and the loose material removed with a hand au er. The dee er borin s were reamed-out also with a hand auger, . g p gwhich provided detailed characteristics of the cemented sandy silts hardpan. Two inches.of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted in each of the eight test borings. All perc test borings were then pre-saturated with 12 inches of water on Thursday, May 13, 1000 hrs, approximately 24 hrs before.testing. (§6.4) On May 14, 2010, 0800 hrs,percolation testing commenced for both shallow and deep test borings for all four.proposed Parcels. Observed standing water after the 24-hour soak period in the, test borings is illustrated in Table 1 below. For the test borings with no standing water, EHD Pere Test Procedure#2 was conducted. For the test borings that had standing water after the post soak period, EHD Perc Test Procedure-#] was conducted. The last half hour of all the tests-was witnessed by Mike Escotto, R.E.H.S. of the EHD. The maximum acceptable per rate is 60 min/in for shallow perc tests, and 30 min/in for the deep perc tests. The minimum acceptable perc rate is 5 min/in. Consequently, the shallow perc tests for subject. Parcels A, C and D possess acceptable percolation; while only the deeper perc test on Parcel C possesses acceptable percolation, - Chesney Consulting