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F SOIL SUITABILITY STUDY urrounding and On-site Septic System Information A review of Application Permits on file with the Environmental Health Department reveals there has been four Application for Repairs/Additions to septic systems within the on-half mile radius study area, on Linne Road exclusively. This can be considered a medium-to-high number of Repairs/Additions/Replacements considering that older systems (prior to 1999), seepage pits were installed in the underlying gravel strata which extraordinarily managed septic effluent flows. Seepage pits and sumps have been banned by the EHD in this southern region of Tracy due to nitrate impact partially originating from these structures. As referenced,the septic system that serves Mr. Rios' house is antiquated and in need of modernization. The septic tank is a small round structure. Consequently, Mike Huggins of EHD has stipulated that the residential septic system be tied into the new system to serve the proposed wpery. B. Soil Physical Test Results: Particle Size Analysis and Percolation Testing Soil testing was conducted on samples retrieved from a single, exploratory boring. The boring was drilled near the primary disposal area, as denoted on the Percolation Test Form. Physical and analytical chemistry testing were conducted on the samples obtained, discussed below. Particle Size Analysis was done on the three samples by A&L Laboratories of Modesto under the attached Chain of Custody. Laboratory USDA classifications reveal the soil underlying the proposed filter bed location to consist of a clay loam at 0 - 6 inches in depth, a loam at 24 inches in depth and a clay loam at 42 inches in depth. In addition to USDA classifications, the Unified Soil Classification System describes the soil samples(also denoted on the Field Percolation Test Form) as silt(loam), and a lean clayey silt(clay loam), and a silt. These soil classifications are summarized in the Table 1, Page 4. The second physical test to be conducted was a percolation test in the location of the primary filter bed, as described: O 2005, one._per_Q.test bQdugo .4Zjnc=_and one deeper boring to 8.5 ft were drilled with a B-24 Mobile Drill Rig. The deeper boring was drilled to the north of the proposed filter bed area and terminated at 8.5 ft in depth. T ' borin was drilled onl to determine t,__he depth of the area-wide gravel stratum. The boring was then backfilled with soil cuttings. Sidewalls of the 42 inch boring was scored with a pry-bar and the loose material removed with a hand auger. Two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted into each hole. This test boring was pre-saturated with 12 inches of water, approximately 24 hours before the start of testing. No standing water remained after the pre-soak period. On May 5, 2005, percolation testing commenced for the shallow boring. The test boring was refilled to approximately six inches of head water and the percolation tests were conducted over a four-hour period to induce maximum soil saturation. Although EHD Test Procedure#1 could have been run since the six inches of water seeped away after the first 30 minutes, Test Procedure#2 was run to ensure maximum soil saturation cQ4di io under"wor$t case scenario'' onditions. I. .. Page -3- Chesney Consulting