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Sail 5nitabil it), &Nitrate Loading Rmd% Pair 7 Pmpowd�S75mta @t inn,. 17321 Dais M Lodi CA Ptoica No. 6703 tB ails•12 291: 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 ft fn this case. a shallow test and a deeper test were conducted simultaneously A test percoI lion rate of less than 60 minutes per inch for a shallow test, or less than all minutes per inch., or a deep test is considered a "passed" test. The test is to be made within the'-footprint• of the proposed neva leach field. 6.1 Test Description Tile first percolation test occurred on March 15, 2013 North American Testing Service (N.ATS) installed 6-inch diameter soil borings to depths of 42 inches and 68 inches using truck-mounted drilling equipment owned and operated by NAT'S An approximately 2-inch thick laver of"pea-gravel" was placed at the bottom of each boring. and a 4-mch diameter PVC temporary casing perforated at the bottom was place over the gmyel 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 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 from a fixed point of reference. Neither of these tests yielded acceptable percolation rates. On July 1, 2013, a second percolation test was conducted by Live Oak Geo Environmental. Inc of Lodi. A boring was advanced by hand auger to a depth of about 39 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 'Phe test boring was pre-saturated for approximately 24 hours prior to the percolation test The hole was filled with water toil height of 12 inches above the bottom of the boring for the pre- saturation. On the day of testing, the shallow hole was found to be intact and drv_ . 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 4= Inches as a "shallow" test The percolation test in the shallow (39") boring yielded a percolation rate of less than L2 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 2939 Vencmw A"e.M2441 GemPhaw EnArmmmfal Inc Phone (2ni�3n9.t9o; Mtxleraa,CA 953ik r-as: 4(wJl<no_;,•<