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Soil Borings On August 25, 2015, Live Oak excavated a shallow soil boring on each proposed new parcel on the Site for the purpose of conducting percolation tests. The borings were four inches in diameter, 3.35, 3.40, or 3.45 feet deep, and were excavated by hand auger (Table 2). The locations of the borings are indicated on Plate 10. The soil in the borings was similar to that described by the Soil Survey. Clay was encountered to a depth of 2.5 feet, followed by clayey sand to the full depth of each hole. The soil log is presented on Plate 11. Discussion of Soil Lithology Based on the soil observed in the borings, there appears to be moderate potential for percolation in the shallow soil zone at each test location. Sandy soils generally have a much greater potential for percolation than fine-grained or cemented soils. However, a percolation test is the only accepted method for determining the suitability of the soils for a septic disposal area. Percolation test results are discussed in the following section. Percolation Test A shallow percolation test was conducted on each proposed new parcel of the Site. The soil borings discussed above were used for the percolation test holes (Plate 10). Percolation test procedures conformed to San Joaquin County Environmental Health Department policy. Preparation and Presaturation of Percolation Test Holes After the borings were advanced by hand auger and the soils logged, the test holes were completed for the percolation tests. Approximately one inch of pea gravel was placed in the bottom of each open soil boring, followed by a 1.5-inch diameter PVC pipe with perforations on the bottom. Pea gravel was then used to backfill a few inches of the annular space. Live Oak presaturated the percolation test holes approximately 24 hours prior to the percolation testing. Each hole was filled with water to a height of 12 inches above the bottom of the boring for the presaturation. On the day of testing, all four holes were found to be intact and dry. Percolation Test Procedure Live Oak conducted the percolation tests for the borings on August 26, 2015. Due to soil conditions observed, four-hour tests were selected. Water level measurements were taken every 30 minutes during this four-hour period. The last half hour of each test was observed by Ted Tasiopoulos, Senior Registered Environmental Health �— Specialist at the San Joaquin County Environmental Health Department. LOGE 1513 Page 6