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FFarea, 5.3, and 5.4) A Log ofBoring using the Unified Soil Classification System (U.S.C.S.), asd in a 13-foot deep backhoe test pit completed on Parcel 1 near the proposed leachfieldfound on the EHD PERCOLATION TEST DATA SHEET. ly, the underlying soils show a consistent very fine sandy silt with some clay down to the excavation depth of 13 feet. No cemented silts hardpan soil stratum was discernible at depths exceeding five feet. However, as referenced, a cemented silts hardpan was encountered at 40-42 inches, that was sufficient to impeded permeability to an observable degree. t.(§ 6.1) Percolation testing was conducted in the location illustrated on the Tentative Map and Parcel detail map found in Appendix C. The pert test location and subsequent leachfield installation for Parcel 1 are south of where the house is to be built. It is my understanding the septic tank will not be on the building pad. The disposal field is to consist of a gravity filter bed to reduce the disposal area footprint. A future vineyard is to be planted around Parcel 1 and will be under drip irrigation and not flood irrigated; therefore, there should be no problems associated with inundation. This test location maintains sufficient distance requirements between wells, property lines, etc. The following information describes the preparation of the percolation test boring and the actual percolation testing: 4§ 6.2, 6.3 and 6.5) On March 28, 2007, 1740 hrs, one shallow perc test boring of 42 inches and one perc test boring of 36 inches were hand-drilled on proposed Parcel 1. No perc test was conducted on the Designated Remainder, as referenced. A shallower perc test of 36 inches was drilled because at 40-42 inches a thin cemented silts hardpan was encountered in hand-drilling. The test borings are illustrated on the Tentative Map and S.J.C. Aerial Parcel Viewer Map. 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 a three-inch perforated PVC pipe was inserted into each test boring. The borings were pre-saturated on March 29, 2006 at 1130 hrs with 12 inches of clear water. -4-(§ 6.4) On March 30, 2006, 1010 firs,percolation testing commenced. There was no standing water after the 24-hour soak period in the perc tests boring due to the sandy-silty type soil, as illustrated in Table 1 below. Consequently, EHD Perc Test Procedure#2 was conducted. The last half hour of the test was witnessed by Lisa Medina, R.E.H.S. of the San Joaquin County Environmental Health Department. The maximum acceptable perc rate is 60 min/in for shallow perc tests. x(§"5.4 and 6.8) The following Table illustrates the proposed Parcel number, septic system structure to be installed based on the depth of the passing perc rate and the comparatively shallow depth to groundwater, proposed acreage,post soak period status and perc test results for the respective perc test. As illustrated, the 42-inch depth test boring had a perc rate twice as slow as the 36-inch depth, indicating the slower permeability of the encountered cemented silts hardpan. Page -3- Chesney Consulting