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KLEINFELDER 3. PRESENT AND PAST USE The project site currently consists of a vacant field with a small soil stockpile area. Structures which may have been located previously on the parcel are unknown to us. Based on a historical aerial photograph (Plate 1) review and a review of USGS maps, (2- ,J) it appears that the site has been used for agricultural purposes for many years. We saw no evidence that the site has been used as a dairy. We know of no other past uses of the site at this time. 4. SEPTIC PERMITS AND PERFORMANCE SJCEHD files were searched to identify septic permits at parcels in the project vicinity. r� There were three permits on file for the subject parcel. Twenty-one permits were reviewed for parcels located adjacent to or near the subject property. These permits were for new installations and repairs/additions to existing septic systems. The permitted sewage disposal systems were for conventional septic/leach field systems, most with seepage pits or sumps. A summary of the permit information is presented on Plate 3, and copies of the permits are attached. 5. FIELD INVESTIGATION In order to evaluate the subsurface conditions at the project site, on July 20, 2007, one boring was drilled within the proposed leach field area to a depth of about 15 feet below existing site grade. The boring was drilled using a Simco 2800 truck-mounted drill rig equipped with 6-inch O.D. solid-stem auger. The approximate boring location is presented on Plate 2. A representative with our firm maintained a log of the boring and visually classified the soils encountered according to the Unified Soil Classification ( ) Y ke A 4 .see Plate System to the Log of Boring is presented on Plate 5, and the Log Y of Boring is presented on Plate 6. Following completion of the boring, percolation test ole -1 and P-2 were installed -� within the proposed leach field area at depths of a out 5'/z �5ffee below site grade,respectively. The approximate percolation test ho atioresented on Plate 2. Following drilling, the sides of the test holes were scored, and significant loose �J material was removed from the bottom of the hole. The percolation tests were then prepared by first placing about 2 inches of fine gravel at the bottom of the holes and installing a 4-inch diameter, perforated PVC pipe. Before noon on July 23, 2006, about 12 inches of water was placed in the holes for pre-soaking. On July 24, 2006, the percolation tests were started at about 9:30 AM in accordance with SJCEHD / accepted guidelines., using clear potable water. None of the holes exhibited sloughing or caving. The holes were empty of water prior to testing. From a fixed reference point (a marked location on the side of PVC pipe), the drop in water level was measured in approximate 30-minute intervals for four hours, refilling as necessary to maintain the prescribed amount of water over the gravel (SJCEHD Procedure #2). � ►tJ6 81538.G011STo7R801 October 4,2007 9 2007 Kleinfeider Page 2 of 5