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Soil Suitability&Nitrate Loading Study Page 7 Proposed M2 Winery,2900 Peltier Rd,Acarnpo CA J Project No. 670.1A May 28,2013 6.0 PERCOLATION TEST Two separate percolation tests were conducted under permit of the San Joaquin County Environmental Health Department and using EHD guidelines. An agency representative was notified in advance of the test. The agency defines a shallow percolation test as between 36 and 42 inches, while a deep percolation test is between 42 inches and 25 feet. In this case, a shallow test and a deeper test were conducted simultaneously. A test percolation rate of less than 60 minutes per inch for a shallow test,or less than 30 minutes per inch for a deep test is considered a"passed"test. The test is to be made within the"footprint"of the proposed new leach field. 6.1 Test Description The first percolation test occurred on March 13, 2013. North American Testing Service (HATS) installed 6-inch diameter soil borings to depths of 42 inches and 110 inches using truck-mounted drilling equipment owned and operated by NATE. An approximately 2-inch thick layer of"pea-gravel" was placed at the bottom of each boring, and a 4-inch diameter PVC temporary casing perforated at the bottom was place over the gravel pad. The annulus between the casing and the boring was then partially filled with pea-gravel. The PVC casing was used to measure the decreasing water level in the boring. In the 24 hours prior to completing the test,the borings were pre-soaked. The packed boring was filled with water to �3) a depth of 12 inches. The duration of the test was four and a half hours. An electronic well sounder with an accuracy of 0.01 feet was used to monitor the fall of water during the test f from a fixed point of reference. Neither of these tests yield acceptable percolation rates. One May 20, 2012, a second percolation test was conducted by Live Oak Geo 3� Environmental, Inc. of Lodi. A boring was advanced by hand auger to a depth of about 38 inches and was completed for the percolation test. Approximately one inch of pea gravel was placed in the bottom of the 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. The test boring was presaturated for approximately 24 hours prior to the percolation test. The 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 shallow hole was found to be �(o } intact and dry. A 4-hour test was conducted in the presence of the County inspector. 6.2 Test Results The County Environmental Health Department defined a percolation test between 36 and 42 inches as a "shallow" test. The percolation test in the shallow (38") boring yielded a percolation rate of 6.6 minutes per inch, as compared to the minimum acceptable rate of 60 minutes per inch. Based on the test results and the EHD Sewage Standards, the percolation test was successful with respect to use of standard septic system design. Copies of both percolation test reports are attached as Appendix C. 2937 Veneman Ave.,#11240 Geo-Phase Eaviroonentai Inc. Phone: (209)569-0293 Modesto,CA 95356 Fax: (209)569-0295