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Percolation Tests Shallow percolation tests were conducted in both locations. The soil borings discussed above were used for the percolation test holes. 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. NOA 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 NOA conducted the percolation tests for the borings on October 28, 2014. Four-hour tests were selected. Water level measurements were taken every 30 minutes during the four-hour period. The last 30 minutes of each test were observed by Michael Escotto, Senior 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. Percolation Test Results The percolation permit with test results indicated is included in Appendix 2 of this report, along with the pertinent pages of NOA's Geotechnical Investigation discussing the percolation testing. Per San Joaquin County Environmental Health Department's definition, a shallow percolation test hole has a depth between 36 and 42 inches; a satisfactory percolation rate for a shallow test is greater than 1 minute per inch (min/in) drop but less than or equal to 60 min/in drop. For the Site to utilize a standard septic system, one percolation test must demonstrate a satisfactory percolation rate within the proposed septic system disposal field. Details and results of the percolation tests are summarized in the following table: LOGE 20-02 Page 7