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groundwater. The results of the water sample are forthcoming. 3.2 LABORATORY ANALYSES KIFF Analytical LLC (KIFF), of Davis, California send water sample for DBCP (1,2-Dibromo- 3-chloropropanc) testing to Calscience Environmental Laboratories, Inc. (CEL) laboratory. DBCP test performed by using EPA Method 504.1. Groundwater sample analytical results of DBCP tests are presented in the laboratory reports are included in Appendix C. Groundwater samples collected on July 20, 2010 at the site will be analyzed by KIFF for Nitrates using EPA Method 300.0. The results of the water sample for Nitrate testing are forthcoming. 4.0 GROUNDWATER TEST RESULTS 4.1 GROUNDWATER FLOW Depth to groundwater lies between 24 and 28 feet below mean sea level (54 to 58 feet below the ground surface). Soil exploration was conducted on March 23, 2010. Soil samples were collected to a depth of 50 feet below ground surface. During soil exploration no groundwater encountered to a depth of 50 feet below ground surface. Per County most current available groundwater maps configuration of the groundwater surface indicates that the groundwater flow direction is generally to the northwest. The horizontal groundwater gradient across the site is at 3.8 foot 0.00072 feet/foot. 4.2 ANALYTICAL RESULTS DBCP test performed in two samples. Results indicated DBCP concentration is 0.097 µg/l and 0.097 gg/l. MCL for DBCP is 0.2 pg/l. Complete report of analytical testing is presented in Appendix C. A sample was taken from the faucet of the domestic well on July 20, 2010 for nitrate testing. The results of the water sample are forthcoming. 5.0 PERCOLATION TESTING Percolation testing was performed at two locations of proposed leach area adjacent the northern property line. The test apparatus included an 8,inches diameter bore holes (shallow and deep pert tests) filled with 2 inches of coarse sand at the base. Test holes were presoaked following their construction for 24 hours before test. The ERD was notified at the start of percolation test. Approximately 6 inches clear water was added over the course sand. Each test ran for a total duration of four hours, with the hydraulic head restored to an initial level at 30 minutes intervals. At the beginning and end of each 30 minutes interval the depth of water in each hole was measured through hole using a rigid steel measuring tap and converted to the rate shown below. Drilling of P-1 encountered Sandy Silt soils in a medium dense and slightly moist conditions to a maximum depth explored of 14 feet. Drilling of P-2 encountered sandy clay slightly moist to a depth of approximately 3.5 feet. Boring logs are included in Appendix D. Test results are presented below. Field percolation test report is included in Appendix E.Nitrate Loading Study (NLS) prepared by James D Robinson, PE, CEG is included in Appendix F. 2 !d