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ground surface, followed by partially cemented, silty sand to the full depth of the hole. The soil logs are presented on Plates 10 through 13. Discussion of Soil Lithology Based on the soil observed in the borings, there appears to be limited to moderate potential for percolation at the test locations. 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 Tests Shallow percolation tests were conducted on Parcels 1, 2, and 4 of the Site; shallow and deep percolation tests were conducted on Parcel 3. The soil borings discussed above were used for the percolation test holes (Plate 9). 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 two inches of pea gravel were placed in the bottom of each open soil boring, followed by a 2.0-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, the holes were found to be intact and dry. Percolation Test Procedure Live Oak conducted the percolation tests for the borings on October 24, 2018. 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 30 minutes of each test were observed by Naseem Ahmed, Registered Environmental Health Specialist at the San Joaquin County Environmental Health Department. An electronic well sounder with a depth accuracy of 1/100th foot was utilized for the water level measurements. The water level was measured against a fixed reference point on the well casing. Measurements were recorded on the data sheet in decimal feet. When necessary after measuring the water level, the holes were refilled with water to a level of six inches or more above the bottom of the hole. LOGE 1809 Page 5