Laserfiche WebLink
faucet of the domestic well on July 20, 2010 for Nitrate testing in groundwater. The 250- <br /> milliliter poly samples were labeled, placed in iced storage and delivered to Curtis and <br /> Tompkins, Ltd, a State of California certified analytical laboratory. A chain-of-custody record <br /> was maintained during shipment of the samples to the laboratory(Appendix Q. <br /> 4.2 LABORATORY ANALYSES <br /> KIFF Analytical LLC (KIFF), of Davis, California send water sample for DBCP (1,2-Dibromo- <br /> 3-chloropropane) testing to Calscience Environmental Laboratories, Inc. (CEL) laboratory. <br /> DBCP test performed by using EPA Method 504.1. Groundwater samples collected on July 20, <br /> 2010 at the site are analyzed by Curtis and Tompkins, Ltd, for Nitrates using EPA Method 300.0. <br /> Groundwater sample analytical results of DBCP and Nitrate tests are presented in the laboratory <br /> reports are included in Appendix C. <br /> 5.0 GROUNDWATER TEST RESULTS <br /> 5.1 GROUNDWATER FLOW ; <br /> Depth to groundwater lies between 24 and 28 feet below mean sea level (54 to 58 feet below the <br /> ground surface). Soil exploration was conducted on March 23, 2010. Soil samples were collected <br /> to a depth of 50 feet below ground surface. During soil exploration no groundwater encountered <br /> to a depth of 50 feet below ground surface. Per County most current available groundwater <br /> maps configuration of the groundwater surface indicates that the groundwater flow direction is <br /> generally to the northwest. The horizontal groundwater gradient across the site is at 3.8 foot <br /> 0.00072 feet/foot. <br /> 5.2 ANALYTICAL RESULTS <br /> i <br /> DBCP test performed in two samples. Results indicated DBCP concentration is 0.097 µg/l and <br /> 0.097 µg/1. MCL for DBCP is 0.2 µg11. Nitrates tests were performed on two samples in <br /> accordance with EPA 300.00. Results indicated concentrations of Nitrate as NO3 is 59 mg/L and <br /> 60 mg/L. MCL for Nitrate as NO3 in drinking water is 45 µg/1. Complete report of analytical <br /> testing is presented in Appendix C. <br /> 6.0 PERCOLATION TESTING <br /> Percolation testing was performed at two locations of proposed leach area adjacent the northern <br /> property line. The test apparatus included an 8 inches diameter bore holes (shallow and deep h <br /> perc tests) filled with 2 inches of coarse sand at the base. Test holes were presoaked following <br /> their construction for 24 hours before test. The EHD was notified at the start of percolation test. <br /> Approximately 6 inches clear water was added over the course sand. Each test ran for a total <br /> duration of four hours, with the hydraulic head restored to an initial level at 30 minutes intervals. G <br /> At the beginning and end of each 30 minutes interval the depth of water in each hole was <br /> measured through hole using a rigid steel measuring tap and converted to the rate shown below. <br /> Drilling of P-1 encountered Sandy Silt soils in a medium dense and slightly moist conditions to a <br /> I� <br /> 3 <br />