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Discussion of Soil Lithology Based on the soil observed in the borings, there appears to be good potential for percolation in both the shallow and the deep soil zones. 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 Shallow percolation tests were conducted on seven parcels; shallow and deep tests were conducted on three parcels. The soil borings discussed above were used for the percolation test holes. 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 soil logged, the test holes were completed for the percolation testing. 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 each percolation test hole approximately 24 hours prior to the percolation testing. The holes were filled with water to a height of 12 inches above the bottom of the boring for the presaturation. On the day of testing, each hole was found to be intact and dry. Percolation Test Procedure Live Oak conducted the percolation tests for the borings on August 31 through September 2, 2022. Based on initial percolation rates observed, one-hour tests were selected for all the parcels. Water level measurements were taken every 10 minutes during the one-hour period. The last 30 minutes of each test were observed by Aldara Salinas or Aaron Gooderham, Registered Environmental Health Specialists 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, each hole was refilled with water to a level of approximately six inches above the bottom of the hole. LOGE 2217 Page 6