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Valley 'Vater Treatment Page 6 <br /> Groundwater Monitoring Well Construction <br /> Project No. 480:2 <br /> March 14, 2006 <br /> 4 <br />' 3.0 FIELD & ANALYTIC DATA <br />' 3.1 Site Geology & Hydrology <br /> Site Geology <br /> The geologic character of sediments observed during the completion of the <br />' borings in the area can generally be characterized as yellowish brown clay and <br /> silt with minor amounts of sand. The soils are fine-grained and poorly <br />' permeable. Details are shown in the soil boring logs attached as Appendix B. <br /> Hydrology <br />' Evaluation of the site's hydrologic conditions included a review of the County <br /> Flood Control and Water Conservation District's, Spring 1999 Groundwater <br /> Report. Based on the map information, the first groundwater lies about 20 feet <br />' below grade and flows in a northeasterly direction. <br /> Data from the new monitoring wells show that locally, the depth to first <br /> groundwater is about 8 feet below grade. Using the survey information and <br /> groundwater monitoring data, a three-point calculation was made of the slope of <br /> the groundwater surface (see Figure 3). The calculation indicated that on <br /> December 16, 2005, the groundwater surface at this site was flowing on bearing <br /> of approximately N3°W with a gradient of 0.0382 ft/ft. This is directly away <br /> from the ship channel adjacent along the south side of the Property. <br /> 3.2 Soil & Groundwater Analyses <br /> Soil <br /> At least one soil sample from each boring was submitted to Argon Analytical <br /> Services Ceres (State Certified Laboratory #2359) following Chain of Custody <br /> protocol. All samples were tested for the presence of benzene, toluene, <br /> ethylbenzene, and xylene (BTEX) using EPA method 8020. Total Petroleum <br /> Hydrocarbons measured as gasoline, were analyzed using EPA method 8015m. <br /> Groundwater <br /> Groundwater samples were collected from each of the four groundwater <br /> monitoring wells on December 16, 2005. All samples were submitted to Argon <br /> I laboratories following Chain , of Custody protocol and were tested for the <br /> presence of benzene, toluene, ethylbenzene, and xylene (BTEX) using EPA <br /> method 602, and Total Petroleum Hydrocarbon as gasoline (TPH-G) by EPA <br /> method 8015m and for the presence of five oxygenated compounds commonly <br /> used as gasoline additives (TBA, MTBE, DPE, ETBE & TAME) and for 1,2 <br /> Dichloroethane using EPA method 8260. The detection limits for these analyses <br /> 2937 Veneman Ave.,#B240 Geo-Phase Environmental Inc. Phone (209) 569-0293 <br /> Modesto, CA 95356 Fax (209) 569-0293 <br />