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%.Wl U <br /> Site Geology and Geohydroloay <br /> The Water Works Corp . (a former environmental consultant to <br /> the property owner) reported in a September, 1991 document <br /> prepared for property located at East Street and Grant Line <br /> Road that the subject intersection is located on <br /> (essentially) level terrain underlain by Pleistocene and <br /> Holocene age flood plain deposits composed of sediments <br /> similar to, and probably conformable to underlying deposits <br /> of alluvium and the Tulare formation. <br /> The flood plain deposits are light to dark-brown and grey <br /> clay, silty sand, and organic materials with locally high <br /> concentrations of salt and alkali . Stream channel deposits <br /> of sand and gravel are also present . <br /> The flood plain deposits of the shallow water bearing zone <br /> have well developed soil profiles and poor permeability. <br /> The base of this zone is poorly defined and probably is <br /> from five to twenty feet below ground surface . Ground- <br /> water is less than ten feet below grade at the site and <br /> throughout most of theracy area. Groundwater flow is <br /> generally to the north Y Site specific calculations <br /> performed during February, 1994 showed groundwater to be <br /> moving N-680 -E with a hydraulic gradient of .002 ft/ft . . <br /> Distribution of Hydrocarbon Contamination in Soil and <br /> shallow Groundwater _.__...� <br /> During October of 1993 , EPM Technologies advanced nine ( 9) <br /> soil borings well into the saturated zone along the <br /> northern boundary of the site . Discrete soil samples and <br /> grab water samples were obtained from each borehole. Soil <br /> profiles and contamination isoconcentration contours and <br /> soil profiles developed. The results of certified <br /> laboratory analyses performed on each sample are presented <br /> in Tables 1 and 2 , below. isoconcentration contour maps <br /> for Total Petroleum Hydrocarbons as Gasoline (TPH-G) in <br /> soil (showing levels of gasoline contamination at 8+ feet) <br /> and in shallow groundwater are enclosed as Figures 4 and 5 . <br /> Page 2 <br />